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What is A 12 year old boy presents with hemetemesis, malena and mild splenomegaly. There is no obvious jaundice or ascitis. The most likely diagnosis is and explain in detail?
.Extra Hepatic Poal Venous Obstruction 5-6 years of age hematemesis with or without melena splenomegaly depends on duration of blockage liver usually normal in size ascites is rare variable extent of growth retardation is seen ESSENTIAL PEDIATRICS,O.P.GHAI,PG NO:289,7th edition