Renal Calculi: An Unusual Presentation of T-Cell Acute Lymphoblastic Leukemia.

Spontaneous tumor lysis syndrome is a rare initial presentation of hematologic malignancy in children that typically presents with complications of electrolyte derangement, specifically hyperkalemia, hyperphosphatemia, and hyperuricemia. We report a case of a 5-year-old boy who presented to the emergency department with gross hematuria, abdominal pain, and vomiting and was ultimately diagnosed with uric acid nephrolithiasis and acute renal failure secondary to spontaneous tumor lysis syndrome in the setting of T-cell acute lymphoblastic leukemia. Tumor lysis syndrome is considered an oncologic emergency, and in this case, the child required urgent treatment with potassium-binding agents, rasburicase, and hemodialysis. This case demonstrates that occult hematologic malignancy should be suspected in cases of nephrolithiasis and acute renal failure when found in conjunction with hyperuricemia despite a normal complete blood count at the time of presentation.