Ascites revealing peritoneal and hepatic extramedullary hematopoiesis with peliosis in agnogenic myeloid metaplasia: case report and review of the literature. A 61-year-old man presented with ascites in the course of agnogenic myeloid metaplasia (AMM). Ascitic fluid was exudative and contained mature and immature leukocytes, erythroid cells, and megakaryocytes as observed on a bone marrow smear. Peritoneal biopsy showed myeloid metaplasia, and liver biopsy revealed intrasinusoidal myeloid metaplasia and peliosis. Ascites cleared after abdominal radiotherapy but treatment resulted in transient aplasia. Subsequently, portal hypertension was demonstrated by hepatic transjugular catheterization. Complications of splenomegaly led to splenectomy and splenorenal shunt followed by fatal acute hepatitis and septic shock. A review of the literature and an analysis of mechanisms of ascites occurring in AMM, especially peritoneal implants of myeloid tissue and occurrence of peliosis in myeloproliferative disorders, are presented. 