Which of the following is associated with an intrinsic defect in the RBC membrane?

Ans. b. Hereditary spherocytosis (Ref: Harrison 19/e p651, 18/e p872, 873; Robbins 9/e p632-634, 8/e p642)Hereditary spherocytosis is associated with an intrinsic defect in the RBC membrane.Hereditary SpherocytosisCharacterized by defect in one of the proteins in the cytoskeleton of RBC membrane, leading to loss of membrane, and hence decreased ratio of surface area to volume and consequently spherocytosis.Autosomal dominantQProteins that may be defective:MC membrane defect: AnkyrinProtein Defects causing Hereditary Spherocytosis: AnkyrinQ > Protein 3 >Spectrin >PalladinClinical Features:One characteristic clinical presentation is anemia, splenomegaly and jaundiceQStable clinical course is sometimes punctuated by an aplastic crisis, usually triggered by an acute parvo virus infectionQ.Characteristic Laboratory abnormalities:MCV is decreasedQMCHC is increasedQOsmotic fragility is increasedQDiagnosis:Diagnosis is readily established by a positive direct Coomb's testQ.Treatment:Splenectomy is treatment of choiceQ.