Fulminant Acute Lymphoblastic Leukemia in Sudden Unexpected Pediatric Death.

Sudden unexpected death due to neoplastic disease in infancy and childhood (also known as SUDNIC) is a rare but important cause of pediatric death. Of these deaths, hematologic malignancy is a notable underlying cause. This condition may pose diagnostic challenges for forensic pathologists because clinical history may be limited and gross findings may be atypical but nonspecific. We report a case of a previously healthy 18-month-old found unresponsive in bed. At autopsy, there was bilateral nephromegaly and multiorgan pallor, as well as enlarged lymph nodes. Microscopic examination revealed leukemic infiltration of the kidneys, as well as bone marrow, lymph nodes, and many other organs. Immunohistochemical staining was positive for Tdt and CD43, consistent with acute lymphoblastic leukemia (ALL). Cause of death was determined to be acute renal failure from the fulminant ALL; the manner of death was natural. This case highlights hematologic malignancy as an important cause of SUDNIC. Recognition of nephromegaly and renal pallor should prompt consideration of leukemia and, when suspected, should guide relevant specimen collection for ancillary studies such as flow cytometry to confirm the diagnosis.