All of the following are causes of aplastic anemia except: March 2008

Ans. C: Hepatocellular carcinoma Congenital ---or inherited causes of aplastic anemia (20%) Patients usually have dysmorphic features or physical stigmata. On occasion, marrow failure may be the initial presenting feature. - Fanconi anemia Dyskeratosis congenita Cailage-hair hypoplasia Pearson syndrome Amegakaryocytic thrombocytopenia - Familial aplastic anemia Acquired causes of aplastic anemia (80%) Idiopathic factors Infectious causes, such as hepatitis viruses, EBV, human immunodeficiency virus (HIV), parvovirus, and mycobacteria Toxic exposure to radiation and chemicals, such as benzene Drugs and elements, such as chloramphenicol, phenylbutazone, and gold may cause aplasia of the marrow. PNH is caused by an acquired genetic defect limited to the stem-cell compament affecting the PIGA gene. Mutations in the PIGA gene render cells of hematopoietic origin sensitive to increased complement lysis.