Hepatic involvement in congenital acute megakaryoblastic leukemia: a case report with emphasis on the liver pathology findings.

We report the case of a 4-week-old infant diagnosed with acute megakaryoblastic leukemia with the t (1;22) (p13, q13) who presented with ascites caused by massive infiltration of hepatic sinusoids by leukemic cells. The bone marrow by microscopy and flow cytometry and the peripheral blood smear did not initially show the presence of blasts. Marrow fibrosis appeared after infiltrative disease in the liver and liver fibrosis. We describe the microscopic liver findings and associated clinical presentation that, in the absence of bone marrow involvement, can be difficult to diagnose as leukemia. Few cases have been reported in the medical literature with the liver as the primary site of involvement in congenital leukemia. Awareness of this unusual clinical presentation and of the characteristic liver pathology may facilitate the pathologic diagnosis.