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What is Splenomegaly is a feature of all except: and explain in detail?
Ans: A (Aplastic anemia) Ref: Harrison's 18th edn, pg 467Explanation:Aplastic anemia is pancytopenia w ith hypocellular bone marrow. It does not produce any organomegaly.Causes of massive splenomegaly :CMLMyelofibrosisHairy cell leukemiaChronic malariaKala azarExtrahepatic portal vein thrombosisOther causes:Acute malariaTyphoidInfectious mononucleosisInfective endocarditisLeptospirosisTuberculosisViral hepatitisHIVSLERheumatoid arthritisHIVHemolytic anemiaMechanisms of Splenomegaly:Hypertrophy/hyperplasia related to specific splenic function: RES hyperplasia in hereditary- spherocytosis, thalassemia; immune hyperplasia as in infectious mononucleosis. SLEPassive congestion: As in portal hypertensionInfiltrative diseases: Lymphomas, Myelopro-liferative disorders