Ahmad Adi, MD

• Department of Cardiothoracic Anesthesiology
• Cleveland Clinic
• Cleveland, Ohio

The reduced deformability of spherocytes impedes their passage through the interendothelial slits separating the splenic cords of the red pulp from the splenic sinuses allergy testing no insurance 10 ml astelin with amex. The decrease in red cell deformability is primarily related to a loss of surface area allergy medicine xy buy astelin with mastercard, and to a lesser extent allergy treatment during pregnancy order cheap astelin line, to an increase in internal viscosity resulting from mild cellular dehydration allergy shots asthma generic 10 ml astelin overnight delivery. Spherocytes have decreased deformability and are trapped in the spleen where the membrane is further damaged by splenic conditioning milk allergy symptoms in 5 week old cheap astelin online visa, which ultimately results in hemolysis. Spherocytes are "conditioned" during erythrostasis in the spleen and become more osmotically fragile and increasingly spherocytic. In the remaining patients, the disorder may be autosomal recessive or result from de novo mutations, which is relatively common. The typical clinical picture combines evidence of hemolysis (anemia, jaundice, reticulocytosis, gallstones, splenomegaly) with spherocytosis (spherocytes on the blood film and increased osmotic fragility) and a positive family history. Physical examination should seek signs such as scleral icterus, jaundice and splenomegaly. Clinical Classification of Hereditary Spherocytosis Carrier Hemoglobin (g/L) Reticulocytes (%) Bilirubin (mg/dL) Blood film Normal 0­1 1. In children, anemia is the most frequent finding (50% of cases), followed by splenomegaly, jaundice, or a positive family history. Hemolysis may be incompletely compensated with mild to moderate anemia (see Table 47­3). The moderate anemia may often be asymptomatic; however, fatigue and mild pallor or both may be present. Jaundice may be intermittent and is seen in approximately half of patients, usually in association with viral infections. When present, jaundice is acholuric, characterized by unconjugated hyperbilirubinemia without detectable bilirubinuria. Typically, the spleen is modestly enlarged (2­6 cm below the costal margin), but it may be massive. However, given the pathophysiology and response of the disease to splenectomy, such a correlation probably exists. Splenomegaly is mild, reticulocyte counts are generally less than 6%, and spherocytes on the blood film may be minimal, which complicates the diagnosis. Many of these individuals escape detection until adulthood when they are being evaluated for unrelated disorders or when complications related to anemia or chronic hemolysis occur. Hemolysis may become severe with illnesses that further increase splenomegaly, such as infectious mononucleosis, or may be exacerbated by other factors, such as pregnancy or sustained, vigorous exercise. A small number (<5%) of patients have severe disease with life-threatening anemia and are transfusion dependent. Added to the risks of recurrent transfusions, patients often suffer from hemolytic and aplastic crises and may develop complications of severe uncompensated anemia, including growth retardation, delayed sexual maturation, and aspects of thalassemic facies. Approximately 1% of the population in North America and parts of Europe is estimated to be silent carriers. Coinheritance of Gilbert syndrome markedly increases the risk of gallstone formation. Although gallstones have been detected in children, they mainly occur in adolescents and young adults. Interval ultrasonography allows prompt diagnosis and treatment and prevents complications of symptomatic biliary tract disease, including biliary obstruction, cholecystitis, and cholangitis. Hemolytic, Aplastic, and Megaloblastic Crises Hemolytic crises are the most common, are usually associated with viral illnesses, and typically occur in childhood. Aplastic crises following virally induced marrow suppression are uncommon but may result in severe anemia, requiring hospitalization and transfusion with serious complications, including congestive heart failure or death. The virus selectively infects erythropoietic progenitor cells and inhibits their growth leading to the characteristic finding of a low number of reticulocytes despite severe anemia. Terms of Use · Privacy Policy · Notice · Accessibility Other Complications Aplastic crises following virally induced marrow suppression are uncommon but may result in severe anemia, requiring hospitalization and transfusion with serious complications, including congestive heart failure or death. The virus selectively infects erythropoietic progenitor cells and inhibits their growth leading to the characteristic finding of a low number of Access Provided by: reticulocytes despite severe anemia. In severe cases, skeletal abnormalities resulting from expansion of the marrow can occur. Several tests are available in routine diagnostic laboratories, whereas more sophisticated technologies to identify the defective protein and gene mutations are only performed in specialized research-oriented laboratories. When examining blood from a patient with suspected spherocytosis, a high-quality film with the erythrocytes properly separated and some cells with central pallor in the field of examination are important because spherocytes can be an artifact. Erythrocyte Indices Most patients have mild to moderate anemia with hemoglobin in the 90­120 g/L range (see Table 47­3). The reticulocyte count may appear to be elevated disproportionately relative to the degree of anemia. Reticulocytosis, variably increased lactate dehydrogenase, increased urinary and fecal urobilinogen, unconjugated hyperbilirubinemia, and decreased serum haptoglobin reflect hemolysis and increased erythropoiesis (Chap. Erythrocyte Fragility Tests Spherocytes have a decreased surface area relative to cell volume and this renders them osmotically fragile. The most common osmotic fragility test measures lysis of red cells, either from freshly drawn blood or after incubation of the sample at 37°C for 24 hours, in a range of hypotonic concentrations of sodium chloride. Spherocytes typically swell and burst at higher sodium chloride concentrations than do normal biconcave disk-shaped red cells. Other tests based on the same principle measure the rate and extent of cell lysis in buffered glycerol solutions and include the glycerol lysis test and the acidified glycerol lysis test. This test is commonly used, but flow cytometers from different manufacturers give different values for the mean fluorescence intensity; consequently, there are no universal reference ranges. Highly specialized equipment is required for this procedure, which limits its availability. The sensitivity of this test varies between laboratories and different patient populations, but typically an abnormality is defined in 72% to 93% of cases. Neonates with unexplained hemolytic anemia also may be difficult 52 Page 24 / to , Theresa L. However, the results may be inconclusive or the patient may have had recent transfusions, which present a diagnostic challenge. The quality of the sequencing reads should be assessed and the data should be subjected to a thorough and rigorous analysis. The sequences should be processed through various filters to remove irrelevant variants using the numerous software programs and databases that are available. Programs to predict pathogenicity of mutations and to model these changes on the 3-dimensional structure of the defective proteins have been developed to assist the analysis. Potential pathogenic mutations should be validated by Sanger sequencing and family studies, if possible, and the results should correlate with biochemical and clinical data on the patient. Criteria to classify the variants are described and a standard gene nomenclature is also recommended to enable unambiguous designation of a variant. Occasional spherocytes are seen in patients with a large spleen (eg, in cirrhosis or myelofibrosis) or in patients with microangiopathic anemias (Chap. Terms of Use · Privacy Policy · Notice · Accessibility Splenectomy Page 25 / 52 bites from snakes, spiders, bees, and wasps (Chaps. Countway Medical Library Access Provided by: Occasional spherocytes are seen in patients with a large spleen (eg, in cirrhosis or myelofibrosis) or in patients with microangiopathic anemias (Chap. Thus, splenectomy cures or alleviates the anemia in the overwhelming majority of patients, reducing or eliminating the need for red cell transfusions, which has obvious implications for future iron overload and hemochromatosis-related end-organ damage. Postsplenectomy, spherocytosis, and altered osmotic fragility persist, but the "tail" of the osmotic fragility curve, created by conditioning of a subpopulation of spherocytes by the spleen, disappears. Erythrocyte life span nearly normalizes, and reticulocyte counts fall to normal or near-normal levels. Changes typical of the postsplenectomy state, including Howell-Jolly bodies, target cells, Pappenheimer bodies (siderocytes), and acanthocytes (Chaps. If such patients have symptomatic gallstones, a combined cholecystectomy and splenectomy can be performed, particularly if acute cholecystitis or biliary obstruction has occurred. There is no evidence to indicate any benefit to performing cholecystectomy and splenectomy separately, as done in the past. Because the risk of postsplenectomy sepsis is very high during infancy and early childhood, splenectomy should be delayed until age 5 to 9 years if possible and to at least 3 years if feasible, even if chronic transfusions are required in the interim. In fact, a delay may be harmful because the risk of cholelithiasis increases dramatically in children older than 10 years. When splenectomy is warranted, laparoscopic splenectomy has become the method of choice in centers with surgeons experienced in the technique. Laparoscopic splenectomy results in less postoperative discomfort, a quicker return to preoperative diet and activities, shorter hospitalization, decreased costs, and smaller scars. The risk of bleeding increases during the operation and approximately 10% of laparoscopic operations (for all causes) must be converted to standard splenectomies. Even very large spleens (>600 g) can be removed laparoscopically because the spleen is placed in a large bag, diced, and eliminated via suction catheters. Partial splenectomy via laparotomy has been advocated for infants and young children with significant anemia associated with erythrocyte membrane disorders. Coetzer Prior to splenectomy, patients should be immunized with vaccines against pneumococcus, Haemophilus influenzae type B, and meningococcus, ©2021 McGraw Hill. Terms of Use · Privacy Policy · Notice · Accessibility preferably several weeks preoperatively. Postsplenectomy, prophylactic antibiotics (penicillin V 125 mg orally twice daily for patients younger than 7 years or 250 mg orally twice daily for those Partial splenectomy via laparotomy has been advocated for infants and young children with significant anemia associated with erythrocyte membrane disorders. Use of prophylactic antibiotics postsplenectomy for prevention of pneumococcal sepsis is controversial. Postsplenectomy, prophylactic antibiotics (penicillin V 125 mg orally twice daily for patients younger than 7 years or 250 mg orally twice daily for those older than 7 years, including adults), are recommended for at least 5 years postsplenectomy by some and for life by others. The optimal duration of prophylactic antibiotic therapy postsplenectomy is unknown. Failure may result from an accessory spleen missed during splenectomy, from development of splenunculi as a consequence of autotransplantation of splenic tissue during surgery, or from another intrinsic red cell defect, such as pyruvate kinase deficiency (Chap. Recurrence of hemolytic anemia years or even decades following splenectomy should raise suspicion of an accessory spleen particularly if Howell-Jolly bodies are no longer found on blood film (Chaps. Definitive confirmation of ectopic splenic tissue can be achieved by a radiocolloid liver­spleen scan or a scan using 51Cr-labeled, heatdamaged red cells. A history, physical examination for splenomegaly, complete blood count, examination of the blood film for spherocytes, and a reticulocyte count should be obtained for parents, children, and siblings, if available. In 1904, Dresbach, a physiologist at Ohio State University in Columbus, Ohio, published the first description of elliptical red blood cells in one of his students, which were noticed during a laboratory exercise in which the students were examining their own blood. The demonstration of elliptocytosis in 3 generations of 1 family established the hereditary nature of this disorder. Note the prominent micropoikilocytosis, microspherocytosis, and fragmentation especially after splenectomy. In the United States, the incidence is estimated to be 1 in 2000­4000 individuals. Investigations of erythrocyte membrane proteins in these disorders have identified abnormalities in -spectrin, -spectrin, protein 4. When the integrity of the skeleton is compromised, the capacity of the erythrocyte to undergo flow-induced deformation and rearrangement of the skeleton is reduced. Disruption of the dynamic dissociation and reassociation of spectrin tetramers causes mechanical instability of the membrane, which precludes the recovery of the normal biconcave disk shape of the cell after prolonged and repeated unidirectional axial distortion in the microcirculation. This functional defect results in an increased percentage of spectrin dimers relative to tetramers,135 which is reflected on a structural level by an abnormal tryptic digest pattern of the protein, whereby the normal peptide is decreased with a concomitant increase in an abnormal peptide of lower molecular weight. Most of the defects affect the 80-kDa I domain of -spectrin and of the 9 structural variants the most common are SpI/74, SpI/65, and SpI/46 or 50a. The majority of the mutations are missense mutations that substitute highly conserved amino acids or those in close proximity. The abnormal amino acids typically have a different charge, or in the case of glycine or proline substitutions, they disrupt the helical structure of the spectrin repeats, which alter the interactions between and subunits. Several mechanisms have been identified by which the mutations impair spectrin tetramer formation. At the protein level, these mutations are found at the selfassociation site, which consists of helix C of the 0 partial spectrin repeat that interacts with helices B and C of -spectrin partial repeat 17 to form a complete triple helical bundle. This suggested that their effect on tetramer formation was exerted through defective molecular recognition and disruption of protein­protein interactions at the contact site, rather than an altered structure. Missense mutations are found in both helices A and B of the 131,132,141­144 through defective molecular recognition and disruption of protein­protein interactions at the contact site, rather than an altered structure. These findings contrasted with mutations in the 17 repeat of -spectrin, which perturbed the structural conformation of this partial repeat and the adjacent Countway Medical Library Access Provided by: 16 repeat. Missense mutations are found in both helices A and B of the 17 repeat,131,132,141­144 but some in helix A are particularly severe, causing extreme fetal or neonatal anemia and nonimmune hydrops fetalis when inherited in the homozygous state. When heterodimers are aligned, repeats 0 to 3 are not in contact with -spectrin, and they represent an open dimer configuration, which facilitates tetramer formation. Open dimers are in equilibrium with closed dimers whereby 0 to 3 are folded onto 16 and 17 of the same dimer, thus preventing bivalent tetramer formation. These red blood cells are mechanically unstable and fragment at moderate shear stress, but the stability can be restored by reconstituting the deficient red cells with protein 4. In patients with spectrin heterodimer self-association defects, the resultant increase in spectrin dimers and concomitant decrease in spectrin tetramers, weakens the membrane skeleton and facilitates the formation of elliptocytes under circulatory shear stress. The most important determinants of the severity of hemolysis in these patients are the percentage of spectrin dimers and the spectrin content of the membrane skeleton. These parameters are influenced by the degree of dysfunction of the mutant spectrin, and the gene dose (heterozygote vs homozygote or compound heterozygote). This heterogeneity is a result of the inheritance of modifier alleles or additional defects. Coinheritance of other molecular defects also plays a role in modifying the clinical expression.

Evidence for distinct pathways of hepcidin regulation by acute and chronic iron loading in mice allergy goggles discount generic astelin uk. Elevated growth differentiation factor 15 expression in patients with congenital dyserythropoietic anemia type I allergy medicine to dry up sinuses astelin 10 ml on line. Autosomal dominant hereditary hemochromatosis associated with a novel ferroportin mutation and unique clinical features allergy medicine zyrtec buy cheap astelin 10 ml online. Mutant antimicrobial peptide hepcidin is associated with severe juvenile hemochromatosis allergy medicine singulair cheap astelin 10 ml fast delivery. Resistance of ferroportin to hepcidin binding causes exocrine pancreatic failure and fatal iron overload allergy austin order astelin australia. Functional analysis and theoretical modeling of ferroportin reveals clustering of mutations according to phenotype. Association of ferroportin Q248H polymorphism with elevated levels of serum ferritin in African 257. Resistance of ferroportin to hepcidin binding causes exocrine pancreatic failureCountway Medical Library and fatal iron overload. Expression of hepcidin is down-regulated in TfR2 mutant mice manifesting a phenotype of hereditary hemochromatosis. Hemojuvelin acts as a bone morphogenetic protein co-receptor to regulate hepcidin expression. Hemojuvelin is essential for dietary iron sensing, and its mutation leads to severe iron overload. Deferoxamine prevents cardiac hypertrophy and failure in the gerbil model of iron-induced cardiomyopathy. The iron-loaded gerbil model revisited: effects of deferoxamine and deferiprone treatment. Hereditary hemochromatosis is characterized by a clinically definable arthropathy that correlates with iron load. Increased risk of arthropathies and joint replacement surgery in patients with genetic hemochromatosis: a study of 3,531 patients and their 11,794 first-degree relatives. Prevalence of hepatic iron overload and association with hepatocellular cancer in end-stage liver disease: results from the National Hemochromatosis Transplant Registry. Routine transferrin saturation measurement in liver clinic patients increases detection of hereditary haemochromatosis. Raised serum ferritin concentration in hereditary hyperferritinemia cataract syndrome is not a marker for iron overload. Reversal of end-stage heart failure in juvenile hemochromatosis with iron chelation therapy: a case ©2021 McGraw Hill. Reversal of end-stage heart failure in juvenile hemochromatosis with iron chelation therapy: a case report. In contrast, the characteristics of anemia that may occur with deficiencies of other micronutrients, such as some of the other vitamins and minerals, are poorly defined and relatively rare in humans. When present, they usually exist not as isolated deficiencies of one vitamin or one mineral but rather as a combination of deficiencies resulting from malnutrition or malabsorption. In this context, it is difficult to deduce which abnormalities are a result of which deficiency. Studies in experimental animals may not accurately reflect the role of micronutrients in humans. Accordingly, our knowledge of the effect of many micronutrients on hematopoiesis is fragmentary and based on clinical observations and interpretations that may be flawed. Inborn metabolic errors that affect single micronutrient pathways may shed light on the specific effects of those micronutrients on hematopoiesis. The levels normally found in the serum, red cell, and leukocytes are shown in Table 45­1. Unlike iron-deficiency anemia but similar to the anemia of chronic disease, the iron stores in the liver and marrow are increased, the serum transferrin concentration usually is normal or decreased, and administration of medicinal iron does not correct the anemia. However, there is evidence to indicate that vitamin A deficiency may result in impaired iron absorption or utilization5 and that this may be mediated through effects on expression of genes involved in the regulation of intestinal iron absorption. Although vitamin A deficiency is recognized to occur in the United States, the relationship between it and anemia is not known. Regarding mechanism, it has been suggested that vitamin A plays an important role in regulation of the growth and differentiation of erythroid progenitor cells. Evidence linking isolated nutritional deficiencies of pyridoxine, riboflavin, pantothenic acid, and niacin to anemia in patients is inconclusive. In animals, experimentally induced deficiency states are more commonly associated with hematologic abnormalities. Vitamin B6 Deficiency Vitamin B6 includes pyridoxal, pyridoxine, and pyridoxamine. These components are converted to pyridoxal 5-phosphate, which acts as a cofactor in the decarboxylation and transamination of amino acids and in the synthesis of aminolevulinic acid, the porphyrin precursor (Chap. Vitamin B6 deficiency induced in infants is associated with a hypochromic microcytic anemia. A review of more than 200 patients with acquired sideroblastic anemia reported that fewer than 7% showed greater than 15 g/L improvement in hemoglobin concentration. Derangements in these pathways, sometimes involving anemia, are usually the result of inborn errors affecting the pathways of vitamin B6 metabolism and specific pyridoxal phosphate-dependent enzymes or the result of inborn errors that lead to accumulation of small molecules that react with pyridoxal phosphate and inactivate it. The glutathione reductase deficiency induced by riboflavin deficiency is not associated with a hemolytic anemia or increased susceptibility ©2021 McGraw Hill. Terms of Use · Privacy Policy · Notice · Accessibility to oxidant-induced injury (Chap. Other acquired conditions that may influence pyridoxine metabolism include drugs that react with pyridoxal phosphate or that affect its metabolism, malabsorptive states such as celiac disease, and renal dialysis, which leads to increased losses of vitamin B6 Countway Medical Library vitamers from the circulation because these vitamers are bound to plasma albumin. The glutathione reductase deficiency induced by riboflavin deficiency is not associated with a hemolytic anemia or increased susceptibility to oxidant-induced injury (Chap. It has been suggested that riboflavin deficiency causes anemia,25 possibly by interfering with iron release from ferritin. Thiamine Deficiency Megaloblastic anemia, responsive to thiamine, occurs in a childhood syndrome in association with diabetes and sensorineural deafness (Rogers syndrome). There are usually profound anemia and megaloblastic changes with or without ringed sideroblasts in the marrow and occasionally thrombocytopenia. The underlying defect in this condition has been identified as being the result of a defect in the high-affinity thiamine transporter, which primarily affects the synthesis of the ribose portion of nucleic acids as a consequence of the thiamine-dependent pentose-cycle enzyme transketolase. Anemia in these patients responds to the lifelong administration of oral thiamine (25­100 mg/day). When folic acid is given to these subjects in a dose of 50 mcg/day, a prompt hematologic response is observed. Impaired dihydrofolate reductase activity results in an inability to form tetrahydrofolate, the metabolically active form of folic acid (Chap. After ascorbic acid therapy, 5-methyltetrahydrofolate becomes the major urinary folate metabolite. Terms of Use · Privacy Policy · Notice · Accessibility Dietary iron deficiency in children often occurs in association with dietary ascorbate deficiency. Impaired dihydrofolate reductase activity results in an inability to form tetrahydrofolate, the metabolically Countway Medical Library active form of folic acid (Chap. Patients with scurvy and megaloblastic anemia excrete 10-formylfolate as the major urinary folate metabolite. After Access Provided by: ascorbic acid therapy, 5-methyltetrahydrofolate becomes the major urinary folate metabolite. This observation has led to the suggestion that ascorbic acid prevents the irreversible oxidation of methyltetrahydrofolate to formylfolate. Under these circumstances, ascorbic acid therapy produces a hematologic response only if enough folate is present to interact with the ascorbic acid. Iron balance may be compromised by ascorbic acid deficiency because this vitamin serves to facilitate intestinal iron absorption by maintaining iron in the more soluble reduced or ferrous (Fe2+) state. Patients with scurvy, particularly children, may require both iron and vitamin C to correct a hypochromic microcytic anemia. There is a role for ascorbate as a novel modulator of the classical transferrin­iron uptake pathway, which provides almost all iron for cellular demands and erythropoiesis. Ascorbate acts to stimulate transferrin-dependent iron uptake through an intracellular reductive mechanism by stimulating iron mobilization from endosomes. This role of ascorbate might explain how ascorbate deficiency contributes to anemia in iron deficiency. The presence of scurvy in patients with iron overload may protect them from tissue damage. Nutritional deficiency of vitamin E in humans is extremely uncommon because of the widespread occurrence of -tocopherol in food. Hematologic manifestations of vitamin E deficiency in humans are limited to the neonatal period and to pathologic states associated with chronic fat malabsorption. Low-birth-weight infants are born with low serum and tissue concentrations of vitamin E. When these infants are fed a diet unusually rich in polyunsaturated fatty acids and inadequate in vitamin E, a hemolytic anemia frequently develops by 4­6 weeks of age, particularly if iron is also present in the diet. Although it has been reported that modifications of infant formulas have all but eliminated vitamin E deficiency in preterm infants,51 a study in preterm infants noted hemolytic anemia that responded to vitamin E supplementation. Chronic administration of vitamin E 400­800 U/day lengthened the red cell lifespan in some,56,57 but not all,58 studies of patients with hereditary hemolytic anemias associated with glutathione synthetase deficiency or glucose-6-phosphate dehydrogenase deficiency. Administration of vitamin E (450 U/day for 6­36 weeks) to patients with sickle cell anemia significantly reduced the number of irreversibly sickled erythrocytes. Chronic administration of vitamin E 400­800 U/day lengthened the red cell lifespan in some,56,57 Countway Medical Library but not all,58 studies of patients with hereditary hemolytic anemias associated with glutathione synthetase deficiency or glucose-6-phosphate dehydrogenase deficiency. Access Provided by: Administration of vitamin E (450 U/day for 6­36 weeks) to patients with sickle cell anemia significantly reduced the number of irreversibly sickled erythrocytes. Among the cuproenzymes are cytochrome c oxidase, dopamine -hydroxylase, urate oxidase, tyrosine and lysyl oxidase, ascorbic acid oxidase, and superoxide dismutase (erythrocuprein). More than 90% of the copper in the blood is carried bound to ceruloplasmin, an 2-globulin with ferroxidase activity. Copper, in the form of hephaestin,64 converts iron to the ferric (Fe3+) state for its transport by transferrin. Copper deficiency has been described in malnourished children65 and in both infants and adults66­68 receiving parenteral alimentation. There is increasing recognition of copper deficiency associated with anemia occurring as complication after gastric resection or bariatric gastric reduction surgery. These abnormalities include osteoporosis, flaring of the anterior ribs with spontaneous rib fractures, cupping and flaring of long-bone metaphyses with spur formation and submetaphyseal fractures, and epiphyseal separation. Copper deficiency with a resultant microcytic anemia can be produced by chronic ingestion of massive quantities of zinc. This has been reported in patients using excessive quantities of zinc-containing dental fixatives. The serum copper level is thought to be more reliable because ceruloplasmin behaves as an acute phase protein. Despite these limitations, a serum copper level less than 70 mcg/dL (11 mol/L) or a ceruloplasmin level less than 15 mg/dL after age 1 or 2 months can be regarded as evidence of copper deficiency. In later infancy, childhood, and adulthood, serum copper values should normally exceed 70 mcg/dL. Low serum copper values may be observed in hypoproteinemic states, such as exudative enteropathies and nephrosis, and in Wilson disease. In these circumstances, a diagnosis of copper deficiency cannot be established by serum measurements alone but requires analysis of liver copper content or clinical response after a therapeutic trial of copper supplementation. Treatment of copper-deficient infants consists of administration of approximately 2. Zinc deficiency occurs in a variety of pathologic states in humans, including hemolytic anemias such as thalassemia81 and sickle cell anemia. Deficiency of this micronutrient may therefore be seen in conjunction with deficiencies/ of ©2021 McGraw Hill. Terms of Use · Privacy Policy · Notice · Accessibility iron, folate, and vitamin B12 seen in this condition. Zinc deficiency occurs in a Access Provided by: variety of pathologic states in humans, including hemolytic anemias such as thalassemia81 and sickle cell anemia. Deficiency of this micronutrient may therefore be seen in conjunction with deficiencies of iron, folate, and vitamin B12 seen in this condition. An examination of the relationship between serum selenium and hematologic indices found that low serum selenium was independently associated with anemia among older men and women in the United States. Measurements of red cell volume and plasma volume suggest that dilution is a major factor responsible for the reduction in hemoglobin concentration. In persons subjected to complete starvation either for experimental purposes or as treatment of severe obesity, anemia was not observed during the first 2­9 weeks of fasting. It has been suggested that the anemia of starvation is a response to a hypometabolic state with its attendant decrease in oxygen requirements. Kwashiorkor is largely a disease of the underdeveloped world but occasionally is seen even among the children of educated and well-to-do parents when the children are fed an inappropriate diet. The anemia is normocytic and normochromic, but the size and shape of red cells on the blood film vary considerably. The marrow is most often normally cellular or slightly hypocellular, with a reduced erythroid-to-myeloid ratio. Erythroblastopenia, reticulocytopenia, and a marrow containing a few giant pronormoblasts may be found, particularly if the child has an infection. With treatment of the infection, erythroid precursors may appear in the marrow and the reticulocyte count may rise. In malnourished communities, anemia with erythroblastopenia resulting from parvovirus B-19 infections (Chap. When nutrition is improved by giving high-protein diets (powdered milk or essential amino acids), reticulocytosis, a slight fall in hematocrit because of hemodilution, and then a rise in hemoglobin level, hematocrit, and red blood cell count occur. An abrupt fall in Page 6 / 15, Ralph Green Ananya Datta Mitra prompt transfusion to restore hemoglobin may be lifesaving.

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Terms of Use · Privacy Policy · Notice · Accessibility 13 Ultrastructural In mice allergy symptoms cough treatment purchase astelin us, primitive red cells are derived from a transient population of primitive erythroid progenitors that is confined to the yolk sac allergy testing kid purchase 10 ml astelin overnight delivery. In mice allergy forecast huntington wv astelin 10 ml order without prescription, targeted disruption of the transcription factors Tal1 allergy shots gone wrong purchase astelin from india, Lmo2 allergy treatment for children generic astelin 10 ml overnight delivery, and Gata-1 each abrogates primitive erythropoiesis in the yolk sac and leads to early embryonic death. Primitive erythroblasts circulate as nucleated cells, accumulate embryonic hemoglobins, and complete terminal differentiation within the vascular network. Although it is widely assumed that primitive red cells remain nucleated throughout their life span, human primitive erythroblasts, like their murine counterparts, ultimately enucleate upon terminal differentiation. The fetal liver thus contains a complex mix of maturing blood cells derived from initially from hematopoietic stem cell­independent hematopoietic progenitors and subsequently from hematopoietic stem cells. Hepatic Hematopoiesis Between 7 and 15 weeks of gestation, 60% of the liver cells are hematopoietic. Erythroid cells differentiate in close physical association with macrophages and extrude their nuclei prior to entering the blood. These fetal liver­derived definitive "macrocytes" are smaller than yolk sac­derived primitive megaloblasts and contain one-third the amount of hemoglobin. Targeted disruption of the Myb transcription factor in mice Page 3 / 39, James Palis George B. Terms of Use · Privacy Policy · Notice · Accessibility in the transcriptional regulation of these distinct forms of erythropoiesis. Targeted disruption of the Myb transcription factor in mice blocks fetal liver erythropoiesis and leads to fetal death. Myeloid and lymphoid cells constitute an increasing proportion of blood cells in the fetal liver as gestation proceeds. The -globin gene cluster is located on chromosome 16 and contains the gene 5 to the pair of -globin genes. The -globin gene cluster is located on chromosome 11 and contains five globin genes oriented 5 to 3 as - A- G-. Terms of Use · Privacy Policy · Notice · Accessibility Adult (A) 22 Marrow Page 4 / 39 9 weeks, 5­45% at term chromosome 16 and contains the gene 5 to the pair of -globin genes. The -globin gene cluster is located on chromosome 11 and contains five Countway Medical Library globin genes oriented 5 to 3 as - A- G-. This globin "switching" is related not only to the relative positions of the globin genes within their respective chromosomal clusters but also to interacting upstream "locus control regions. The - to -globin switch precedes the - to -globin switch as the liver replaces the yolk sac as the main site of erythropoiesis, and primitive erythroid cells are replaced by definitive erythroid cells. Changes in hemoglobin tetramers (A) and in globin subunits (B) during human development from embryo to early infancy. Countway Medical Library Access Provided by: Changes in hemoglobin tetramers (A) and in globin subunits (B) during human development from embryo to early infancy. This rate of decrease in Hgb F production is closely related to the gestational age of the infant and is not affected by the changes in environment and oxygen tension that occur at the time of birth. The mean blood hemoglobin concentration in fetuses progressively increases from 9. Early cord clamping appears to heighten the occurrence of anemia at 2 months and to impair cardiopulmonary adaptation. Normally, the hemoglobin and hematocrit values rise in the first several hours after birth because of the movement of plasma from the intravascular to the extravascular space. Table 6­2 shows the normal red cell values from capillary blood samples for term infants in the first 12 weeks after birth. Table 6­2 shows the normal red cell values from capillary blood samples for term infants in Countway Medical Library the first 12 weeks after birth. Countway Medical Library Access Provided by: Adapted with permission from Matoth Y, Zaizor R, Varsano I. By 3­5 days after birth, nucleated red blood cells are not found normally in the blood of term or premature infants, but they may be present in markedly elevated numbers in the presence of hemolysis or hypoxic stress. Although erythropoietin is present in cord blood, it falls to undetectable levels after birth in healthy infants. The lowest hemoglobin values in the term infant occur at approximately 2 months of age. Erythropoietin can be measured after the 60th postnatal day,97 corresponding to the recovery from physiologic anemia. If there is sufficient stimulus, such as hemolytic anemia or cyanotic heart disease, the newborn infant is able to produce erythropoietin prior to the 60th postnatal day. In infants with a lower percentage of Hgb F (as from transfusion) and, consequently, better oxygen delivery, erythropoietin does not rise until the hemoglobin falls to approximately 9. However, cerebral blood flow was normal in the asymptomatic infants with hyperviscosity, and, consequently, there was no benefit from exchange transfusion. Terms of Use · Privacy Policy · Notice · Accessibility expressed at birth, increasing to adult levels by age 15 years. Moreover, particularly poor expression of Xg has been noted in newborns with trisomy 13, 18, and 21. The i antigen is expressed strongly, whereas the I antigen and the A and B antigens are expressed only weakly on neonatal red cells. The i antigen is a straight-chain carbohydrate that is replaced by the branched-chain derivative, I antigen, as a result of the developmental acquisition of a glycosyltransferase. Anti-A and anti-B isohemagglutinins develop during the first 6 postnatal months, reaching adult levels by 2 years of age. Red Cell Life Span the life span of the red cells in newborn infants is shorter than that of red cells in adults (Chap. The average of several studies of mean half-life of newborn red cells is 60­80 days. Iron and Transferrin the serum iron level in cord blood of the normal infant is elevated compared with maternal levels. The median transferrin saturation falls from almost 65% at 2 weeks to 25% at 1 year, and saturations as low as 10% may be observed in the absence of iron deficiency. Stainable marrow iron begins to decrease after 2 months and is gone by 4­6 months in term infants and earlier in premature infants. The mean partial pressure of oxygen (pO2) at which hemoglobin is 50% saturated with oxygen at 1 day of age in term infants is 19. After birth, the oxygen equilibrium curve shifts gradually to the right, reaching the position of the adult curve by 6 months of age. The position of the curve in premature infants correlates with gestational age rather than with postnatal age,117 and its shift to the adult position is more gradual. The oxygen equilibrium curves are based on the assumption that the hemoglobin (Hgb) concentration is 15 g/dL and that there is full O2 saturation of Hgb at a partial pressure of arterial oxygen (PaO2) of 100 torr. The O2 released is the difference in O2 content between a PaO2 of 90 torr and the mixed venous PaO2 of 40 torr. The O2 available is the difference in O2 content between a PaO2 of 90 torr and a mixed venous PaO2 of 20 torr. This is the maximum O2 available without evoking compensatory mechanisms such as increased cardiac output. Terms of Use · Privacy Policy · Notice · Accessibility Page 10 / 39 the oxygen equilibrium curves are based on the assumption that the hemoglobin (Hgb) concentration is 15 g/dL and that there is full O2 saturation of Hgb at a partial pressure of arterial oxygen (PaO2) of 100 torr. The O2 released is the difference in O2 content between a PaO2 of 90 torr and the mixed Countway Medical Library venous PaO2 of 40 torr. The O2 available is the difference in O2 content between a PaO2 of 90 torr and a mixed venous PaO2 of Access Provided by: the 20 torr. This is maximum O2 available without evoking compensatory mechanisms such as increased cardiac output. Metabolism Many differences have been found between the metabolism of the red cells of newborn infants and that of adults. The glucose consumption in newborn red cells is lower than that in adult red cells. Finally, lower-than-adult activities have been found for several other red cell enzymes, including cytochrome B5 reductase125 and glutathione peroxidase. Newborn red cell membranes have higher total lipid, phospholipid, and cholesterol per cell than adult red cells. Red cells of newborns have the same pattern of membrane proteins on polyacrylamide gel electrophoresis131 and the same rate of mobility in an electric field132 as do red cells from adults. After trypsin treatment of newborn and adult cells, however, there is a difference in electrophoretic mobility, indicating that the surface trypsin-resistant proteins are different. Segel 135 When granulopoiesis was studied in the cord blood, blood, ©2021 McGraw Hill. Terms of Use · Privacy Policy · Notice · Accessibility and urinary colony-stimulating activity are elevated during the period of neutrophilia. Furthermore, preterm infants have a reduced neutrophil storage pool and a restricted capacity to increase their progenitor proliferation, and their neutrophil counts may fall precipitously with neonatal bacterial infection. Terms of Use · Privacy Policy · Notice · Accessibility Table 6­3 gives the values for the white cell and differential counts during the first 2 weeks after birth. The absolute number of segmented neutrophils rises in both term and premature infants in the first 24 hours. White Cell and Differential Counts Table 6­3 gives the values for the white cell and differential counts during the first 2 weeks after birth. In premature infants, the mean values for neutrophils are 5 × 109/L at birth, 8 × 109/L at 12 hours, and 4 × 109/L at 72 hours. The level after the first 72 hours is very stable for an individual infant, whether term or premature. Immature forms, including an occasional promyelocyte and blast cell, may be seen in the blood of healthy infants in the first few days after birth and are more frequent in premature infants than in term infants. As their number decreases, the lymphocyte becomes the most numerous cell and remains so during the first 4 years of life. The onset of the eosinophilia coincided with the establishment of steady weight gain in the infants. Phagocyte Functions Bacterial infections are a major cause of morbidity and mortality in the newborn period. Cellular defense mechanisms and humoral immunity of the newborn differ from those found later in life, and these undoubtedly contribute to the unusual susceptibility to infection noted in the neonatal period. The serum factors necessary for optimal phagocytosis (opsonins) include the immunoglobulins and complement components. In term infants, opsonic activity is normal for Staphylococcus aureus,148,149 but it is low for yeast150 and Escherichia coli. However, in many newborns, both the classical and alternative complement pathways are decreased in activity and in levels of individual components. There is considerable overlap, however, between levels in infants and in control participants. Terms of Use · Privacy Policy · Notice · Accessibility as well as to increase the quantity of circulating neutrophils. Chemotaxis Access Provided by: Chemotactic function of leukocytes is low in neonates, whereas random motility is normal. The defect in chemotaxis may be related to decreased granulocyte deformability and impaired capping of cell surface receptors. Diminished upregulation and surface migration of 2 integrins and fewer L-selectin receptors reduce the ability of neonatal neutrophils to interact with adhesion molecules on the endothelium. Adherence Neutrophil cell adhesion molecules are central to the interaction of neutrophils to the vascular endothelium, and reduction of these molecules diminishes the capacity of neonatal neutrophils to properly adhere and migrate into tissues (Chaps. Phagocytic and Bactericidal Activity Phagocytosis of bacteria and latex granules by neutrophils from premature and term infants is normal. Antimicrobial proteins and peptides are present in neutrophil cytoplasmic granules. Other granule components, such as myeloperoxidase (bacterial killing) and defensins (antimicrobial proteins), are not diminished. Cytokine Effects on Neonatal Phagocytic Function Access Provided by: There is a complex interaction between cytokines produced by lymphocytes and macrophages and the activation status of neutrophils during infection. Low levels of this receptor also impair complement-mediated phagocytosis and oxidative metabolism. The closure time reflects the platelet number, platelet function, and von Willebrand activity. Newborn infants have closure times that are shorter than those of adults, likely related to their higher hematocrits, increased von Willebrand multimers and hence ristocetin cofactor, and higher leukocyte counts. Platelet Aggregation and Metabolism A variety of differences have been described in the platelet function of neonates. These in vitro abnormalities may aggravate the impairment in platelet function and the predisposition to bleeding that result from neonatal diseases, particularly respiratory distress syndrome and sepsis. Terms of Use · Privacy Policy · Notice · Accessibility Maternal aspirin ingestion also results in abnormalities in platelet aggregation in the newborn in response to collagen. These functional changes result from Countway Medical Library intrinsic differences in neonatal compared with adult platelets. Maternal aspirin ingestion also results in abnormalities in platelet aggregation in the newborn in response to collagen. They are presumably caused by trauma associated with passage through the birth canal and disappear within a few days. Platelet Antigens and Glycoproteins Access Provided by: synthesis or to storage pool deficiency of adenine nucleotides. Approximately 2% of the population in the United States of European descent is homozygous for PlA2 and thus are PlA1 negative. The complete expression of the PlA1 antigen during early gestation likely permits sensitization in women who are PlA1 negative even during their first pregnancy. B-Lymphocyte Functions­Humoral Immunity Humoral (B-cell) immunity also develops early in gestation,230 but it is not fully active until after birth.

Tenderness of the sternum may be quite pronounced in chronic myelogenous or acute leukemia allergy symptoms in 7 month old cheap 10 ml astelin with visa, and occasionally in primary myelofibrosis allergy on skin purchase astelin 10 ml without prescription, or if intramedullary lymphoma or myeloma proliferation is rapidly progressive allergy xmas tree astelin 10 ml order otc. Gastrointestinal System Dysphagia is discussed under "Nasopharynx allergy medicine can i give my dog cheap astelin 10 ml online, Oropharynx allergy medicine like singulair purchase cheap astelin line, and Oral Cavity" above. A variety of ill-defined gastrointestinal complaints grouped under the heading "indigestion" may occur with hematologic diseases. Abdominal fullness, premature satiety, belching, or discomfort may occur because of a greatly enlarged spleen, but such splenomegaly may also be entirely asymptomatic. Abdominal pain may arise from intestinal obstruction by lymphoma, retroperitoneal bleeding, lead poisoning, ileus secondary to therapy with the vinca alkaloids, acute hemolysis, allergic purpura, the abdominal crises of sickle cell disease, or acute intermittent porphyria. It also may be prominent in the various forms of intestinal malabsorption, although significant malabsorption may occur without diarrhea. Gastrointestinal bleeding related to thrombocytopenia or other bleeding disorder may be occult but often is manifest as hematemesis or melena. Hematochezia can occur if a bleeding disorder is associated with a colonic lesion. Constipation may occur in the patient with hypercalcemia or in one receiving treatment with the vinca alkaloids. Genitourinary and Reproductive Systems Impotence or bladder dysfunction may occur with spinal cord or peripheral nerve damage caused by one of the hematologic malignancies or with pernicious anemia. Priapism may occur in hyperleukocytic leukemia, essential thrombocythemia, or sickle cell disease. Red urine may also occur with intravascular hemolysis (hemoglobinuria), myoglobinuria, or porphyrinuria. Injection of anthracycline drugs or ingestion of drugs such as phenazopyridine (Pyridium) regularly causes the urine to turn red. Amenorrhea may also be induced by drugs, such as antimetabolites or alkylating agents. Menorrhagia is a common cause of iron deficiency, and care must be taken to obtain a history of the number of prior pregnancies and an accurate assessment of the extent of menstrual blood loss. Semiquantification can be obtained from estimates of the number of days of heavy bleeding (usually <3), the number of days of any bleeding (usually <7), number of tampons or pads used (requirement for double pads suggests excessive bleeding), degree of blood soaking, and clots formed, and from inquiries such as, "Have you experienced a gush of blood when a tampon is removed Back and Extremities Back pain may accompany acute hemolytic reactions or be a result of involvement of bone or the nervous system in acute leukemia or aggressive lymphoma. Arthritis or arthralgia may occur with gout secondary to increased uric acid production in patients with hematologic malignancies, especially acute lymphocytic leukemia in childhood, myelofibrosis, myelodysplastic syndrome, and hemolytic anemia. They also occur in the plasma cell dyscrasias, acute leukemias, and sickle cell disease without evidence of gout, and in allergic purpura. Arthritis may accompany hemochromatosis, although the association has not been carefully established. In the latter case the arthritis starts typically in the small joints of the hand (second and third metacarpal joints), and episodes of acute synovitis may be related to deposition of calcium pyrophosphate dehydrate crystals. Autoimmune diseases may present as anemia and/or thrombocytopenia, and arthritis appears as a later manifestation. Shoulder pain on the left may be a result of infarction of the spleen and on the right of gall bladder disease associated with chronic hemolytic anemia such as hereditary spherocytosis. Administration of malignancies; it is common in the congenital Page 6 / 13, Marshall A. Burns granulocyte- or granulocyte-monocyte colony-stimulating factor may induce bone pain. Terms of Use · Privacy Policy · Notice · Accessibility induce pain at the site of any lesion, including those in bone. Edema of the lower extremities, sometimes unilateral, may occur because of obstruction to veins or lymphatics by lymphomatous masses or from deep venous thrombosis. Arthritis may accompany hemochromatosis, although the Countway Medical Library association has not been carefully established. In the latter case the arthritis starts typically in the small joints of the hand (second and third Access Provided by: metacarpal joints), and episodes of acute synovitis may be related to deposition of calcium pyrophosphate dehydrate crystals. Bone pain may occur with bone involvement by the hematologic malignancies; it is common in the congenital hemolytic anemias, such as sickle cell anemia, and may occur in myelofibrosis. Administration of granulocyte- or granulocyte-monocyte colony-stimulating factor may induce bone pain. In patients with Hodgkin lymphoma, ingestion of alcohol may induce pain at the site of any lesion, including those in bone. Skin Skin manifestations of hematologic disease, including changes in texture or color, itching, and the presence of specific or nonspecific lesions, may be of great importance. The skin in iron-deficient patients may become dry, the hair dry and fine, and the nails brittle. Jaundice may be apparent with pernicious anemia or congenital or acquired hemolytic anemia. The skin of patients with pernicious anemia is said to be "lemon yellow" because of the simultaneous appearance of jaundice and pallor. Jaundice may also occur in patients with hematologic malignancies, especially lymphomas, as a result of liver involvement or biliary tract obstruction. Pallor is a common accompaniment of anemia, although some severely anemic patients may not appear pale. Patchy plaques or widespread erythroderma occur in cutaneous T-cell lymphoma (especially Sézary syndrome) and in some cases of chronic lymphocytic leukemia or lymphocytic lymphoma. The skin is often involved, sometimes severely, in graft-versus-host disease following hematopoietic cell transplantation. Patients with hemochromatosis may have bronze or grayish pigmentation of the skin. Cyanosis occurs with methemoglobinemia, either hereditary or acquired; sulfhemoglobinemia; abnormal hemoglobins with low oxygen affinity; and primary and secondary polycythemia. Cyanosis of the ears or the fingertips may occur after exposure to cold in individuals with cryoglobulins or cold agglutinins. Itching may occur in the absence of any visible skin lesions in Hodgkin lymphoma and may be extreme. Mycosis fungoides or other lymphomas with skin involvement may also present as itching. A significant number of patients with polycythemia vera will complain of itching after bathing. Petechiae and ecchymoses are most often seen in the extremities in patients with thrombocytopenia, nonthrombocytopenic purpura, or acquired or inherited platelet function abnormalities and von Willebrand disease. Unless secondary to trauma, these lesions usually are painless; the lesions of psychogenic purpura and erythema nodosum are painful. Easy bruising is a common complaint, especially among women, and when no other hemorrhagic symptoms are present, usually no abnormalities are found after detailed study. This symptom may, however, indicate a mild hereditary bleeding disorder, such as von Willebrand disease or one of the platelet disorders. Infiltrative lesions may occur in the leukemias (leukemia cutis) and lymphomas (lymphoma cutis) and are sometimes the presenting complaint. Monocytic leukemia has a higher frequency of skin infiltration than other forms of leukemia. Necrotic lesions may occur with intravascular coagulation, purpura fulminans, and warfarin-induced skin necrosis, or, rarely, with exposure to cold in patients with circulating cryoproteins or cold agglutinins. Leg ulcers are a common complaint in sickle cell anemia and occur rarely in other hereditary anemias. They also are associated with long-term hydroxyurea therapy in myeloproliferative neoplasms. Drugs often induce or aggravate hematologic disease, making it essential that a careful history of drug ingestion, including beneficial and adverse reactions, be obtained from all patients. Furthermore, drugs may be ingested in unrecognized form, such as antibiotics in food or quinine in tonic water. Specific, persistent questioning, often on several occasions, may be necessary before a complete history of drug use is obtained. It is very important to obtain detailed information on alcohol consumption from every patient. Nonjudgmental questioning may be successful in identifying agents in this category that the patient is taking. Some patients equate the term "drugs," as opposed to "medicines," with illicit drugs. Terms of Use · Privacy Policy · Notice · Accessibility Chemicals or quinine in tonic water. Specific, persistent questioning, often on several occasions, may be necessary before a complete history of drug use is Countway Medical Library obtained. The use of "alternative medicines" and herbal medicines is common, and many patients will not consider these medications or may actively withhold information about their use. Establishing that the examiner is interested in all forms of ingestants-prescribed drugs, self-remedies, alternative remedies, etcetera -is important to ensure getting the information required. Chemicals In addition to drugs, most people are exposed regularly to a variety of chemicals in the environment, some of which may be potentially harmful agents and result in a deleterious hematologic effect, such as anemia or leukopenia. This information should be supplemented by inquiries about hobbies and other interests that result in work with chemicals, such as glues and solvents. The occurrence of acute immune thrombocytopenia is approximately 1 in 25,000 children vaccinated, occurs within 6 weeks of vaccination, and in the majority of occurrences is self-limited. Nutritional information can be useful in deducing the possible role of dietary deficiency in anemia. The avoidance of certain food groups, as might be the case with vegetarians, or the ingestion of uncooked fish can be clues to the pathogenesis of megaloblastic anemia. In the case of hemolytic disorders, questions should be asked regarding jaundice, anemia, and gallstones in relatives. In patients with disorders of hemostasis or venous thrombosis, particular attention must be given to bleeding manifestations or venous thromboembolism in family members. In the case of autosomal recessive disorders such as pyruvate kinase deficiency, the parents are usually not affected, but a similar clinical syndrome may have occurred in siblings. It is particularly important to inquire about siblings who may have died in infancy, as these may be forgotten, especially by older patients. When sex-linked inheritance is suspected, it is necessary to inquire about symptoms in the maternal grandfather, maternal uncles, male siblings, and nephews. In patients with disorders with dominant inheritance, such as hereditary spherocytosis, one may expect to find that one parent, and possibly siblings and children of the patient, has stigmata of the disease. Ethnic background may be important in the consideration of certain diseases such as - and -thalassemia, sickle cell anemia, glucose-6-phosphate dehydrogenase deficiency, hemoglobin E, and other inherited disorders that are prevalent in specific geographic areas, such as the Mediterranean basin or Southeast Asia. These opportunities include identification of individual genetic risk factors and avoidance of situations that may make a latent disorder manifest. Terms of Use · Privacy Policy · Notice · Accessibility the fraction of the population older than age 65 years has increased dramatically since the 1970s. Countway Medical Library these opportunities include identification of individual genetic risk factors and avoidance of situations that may make a latent disorder manifest. Examples include fostering the elimination of sources of environmental lead that may result in childhood anemia. Prenatal diagnosis can provide information to families as to whether a fetus is affected with a hematologic disorder. Frailty is a pathophysiologic syndrome in older adults that predisposes to a risk for poor health outcomes including falls, disability, hospitalization, and mortality. Numerous quantitative and qualitative instruments have been reported as useful in determining the presence of frailty in the older individual. In essence, the frailty index includes: (a) unintended weight loss, (b) decreased grip strength, (c) ease of exhaustion, (d) slow gait speed, and (e) low physical activity. One group studying patients age 75 years or older with hematologic malignancies has found that gait speed measured with a stopwatch over 4 meters as a sole measurement is strongly correlated with survival. An increased fraction of older individuals are being given chemotherapy or hematopoietic cell transplantation for hematologic (and other system) neoplasms. It has become important to assess frailty in this population as a determinant of the likelihood that intensive therapy can be administered in an older patient. Selecting a frailty index appropriate to general clinical assessment should be a standard part of the examination of an older patient. The skin, eyes, tongue, lymph nodes, skeleton, spleen, liver, and nervous system are especially pertinent to hematologic disease and therefore deserve special attention. The component of skin color related to the blood may be a useful guide to anemia or polycythemia, as pallor may result when the hemoglobin level is reduced and redness when the hemoglobin level is increased. The amount of pigment in the skin modifies skin color and can mislead the clinician, as in individuals with pallor resulting from decreased pigment, or make skin color useless as a guide because of the intense pigmentation present. Alterations in blood flow and in hemoglobin content may change skin color; this, too, can mislead the clinician. Chronic exposure to wind or sun may lead to permanent redness of the skin, and chronic ingestion of alcohol to a flushed face. The degree of erythema of the skin can be evaluated by pressing the thumb firmly against the skin, as on the forehead, so that the capillaries are emptied, and then comparing the color of the compressed spot with the surrounding skin immediately after the thumb is removed. The mucous membranes and nail beds are usually more reliable guides to anemia or polycythemia than the skin. The conjunctivae and gums may be inflamed, however, and therefore not reflect the hemoglobin level, or the gums may appear pale because of pressure from the lips. The gums and the nail beds may also be pigmented and the capillaries correspondingly obscured. In some individuals, the color of the capillaries does not become fully visible through the nails unless pressure is applied to the fingertip, either laterally or on the end of the nail. Burns disease may induce flushing of the thenar and hypothenar eminences of the palm, even in patients with anemia. Terms of Use · Privacy Policy · Notice · Accessibility Cyanosis the mucous membranes and nail beds are usually more reliable guides to anemia or polycythemia than the skin.

References

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