Background: This is a rare instance of acute kidney injury caused by hyperuricemia due to spontaneous tumor lysis syndrome and also the first case of spontaneous tumor lysis syndrome reported in association with myelodysplastic syndrome.
Case presentation: A 53-year-old man presented with abrupt oliguria. Laboratory findings on admission included hyperuricemia, hyperphosphatemia, hypocalcemia, metabolic acidosis and rapidly rising serum creatinine, which were consistent with acute tumor lysis syndrome in the absence of precipitating chemotherapy or radiotherapy. After hemodialysis and oral uric acid lowering therapy, serum uric acid levels returned to normal range and renal function rapidly recovered. The patient was diagnosed as myelodysplastic syndrome eleven months later.
Conclusions: Occult malignancy including solid tumors and hematological malignancies should be carefully evaluated in the case of unexplainable acute kidney injury with hyperuricemia. Aggressive investigations should be thoroughly considered and repeated in this population.