Hematuria and Decreased Kidney Function as Initial Signs of Acute B-Cell Lymphoblastic Leukemia

We report the case of a 14-year-old boy who presented with hematuria and decreased kidney function as initial manifestations of acute lymphoblastic leukemia (ALL). Computed tomography of the abdomen showed extensive retroperitoneal lymphadenopathy and bilateral nephromegaly. The patient's kidney biopsy specimen showed a dense monomorphous interstitial infiltrate of small round blue cells with significant nuclear atypia. Immunohistochemical workup showed positive staining for CD20, CD10, and terminal deoxynucleotidyl transferase (TdT), consistent with ALL. The patient underwent induction chemotherapy, attained remission 4 weeks after induction, and presently is stable in the consolidation phase of chemotherapy. This is an unusual case of ALL involving both kidneys with initial presenting signs of hematuria and decreased kidney function.