Recent management guidelines acknowledge these important considerations when entertaining splenectomy and recommend detailed discussion between health care providers, patient, and family.Ĭlinical manifestations of the spherocytosis syndromes vary widely. Growing recognition and understanding of the long-term risks and complications of splenectomy, including cardiovascular disease, thrombotic disorders, and pulmonary hypertension, and the emergence of penicillin-resistant pneumococci, a concern for infection in overwhelming postsplenectomy infection, have led to reevaluation of the role of splenectomy. Splenectomy via a laparoscopic approach has become the surgical method of choice. Treatment with splenectomy is curative in most patients. This is particularly true for the spherocytosis syndromes where each kindred has a private mutation in one of the spherocytosis genes. Recent molecular studies have revealed that there is also significant genetic heterogeneity in these disorders. These syndromes are characterized by marked clinical and laboratory heterogeneity. Haemolytic in childhood and then normalizes.Disorders of the erythrocyte membrane, including hereditary spherocytosis, hereditary elliptocytosis, hereditary pyropoikilocytosis, and hereditary stomatocytosis, comprise an important group of inherited hemolytic anemias. Overhydrated – moderate to severe haemolytic anaemiaįamilial Pseudohyperkalaemia – universally asymptomatic May have requirement for transfusion in early yearsĪ group of haemolytic conditions resulting from defects in Na/K transfer Rare severe form of HE causing red cell fragmentation, especially in <1 year olds. Incidental finding in most patients with a normal Hb or mild compensated anaemiaĮlliptocytes vary between 10-100% of cells seen Hereditary Elliptocytosis (HE) & Pyropoikilocytosis (HPP) (Hib (Haemophilus influenza B) vaccine is no longer recommended as prevalence is so low in the UK) Pneumococcal - 2 weeks before or 2 weeks after. Splenectomy Vaccinations ( Green Book Jan 2020 ) Remember to give alert card post splenectomy It reduces the risk of bile duct stones, but exposes patient to risk of asplenic sepsis. If child undergoing cholecystectomy for symptomatic gallstones, then concomitant splenectomy is controversial. Concomitant cholecystectomy for asymptomatic gallstones is controversial. If child undergoing splenectomy, cholecystectomy should be performed at the same time for symptomatic stones. Moderate disease that is symptomatic and interfering with lifestyle Gel electrophoresis is the test of choice in atypical cases.įolic acid if mod-severe HS & during pregnancy If diagnosis is equivocal, screening test with EMA binding or cryohaemolysis is sufficiency for diagnosis. Newly diagnosed patients with a family history of HS, typical clinical features and typical lab features (spherocytes, raised MCHC and reticulocytosis) do not require further investigation. Severity usually the same within one family, but highly variable between families. Typically anaemia, jaundice, splenomegaly and reticulocytosis with a negative DAT. Poor correlation between mutation and clinical diagnosisĭefect in the Band 3-Ankyrin-Protein 4.2 complex -> Uncoupling of the cytoskeleton from the cell membrane in localized areas -> formation of spherocytes with reduced flexibility -> destroyed prematurely in spleen. Not usually required where there is a family history to support diagnosis Reference ranges need to be established within each laboratoryīand 3 is the main binding site for EMA -> HS cells will show reduced bindingĪ patient:control ratio of equivocal results or false + See original guideline for sample graphs. Plots curves of deformability that can differentiate the membrane disorders Simple but non-specific – Any fragile red cells will give a positive resultĪlso positive for other causes of spherocytosis – AIHA, pregnancy, CKD, MDS Patient and normal controls compared for concentration at which the cells lyse. HE & HPP -> Reduced protein 4.2 (and reduced a-spectrin in HPP) HS -> Reduced a/b spectrin, Ankyrin, Band 3 or Protein 4.1 Identifies and quantifies membrane contents Gel electrophoresis of red cell membrane proteins SDS-PAGE - Sodium dodecyl sulfate-polyacrylamide gel electrophoresis Quantitative or qualitative deficiencies -> red cell deformity and shortened cell lifespan. in Hereditary Stomatocytosis the leak rate exceeds pump rate à pseudohyperkalaemiaĬytoplasmic surface of the bilayer is covered by a network of spectrin and actin.Ĭontact points between the membrane and spectrin/actin provided by: Passive outflow of K+, which is then pumped back into cells in exchange for Na+Į.g. Outer surface of phospholipid bilayer membrane. Laminated structure composed of two layers with no direct contact
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