Tumour lysis syndrome (TLS) is a constellation of metabolic
complications due to the rapid destruction of malignant
cells, causing renal, cardiac or cerebral dysfunction.
Electrolyte abnormalities include hyperuricaemia, hyperphosphataemia, hyperkalaemia and hypocalcaemia. TLSinduced renal failure is mainly caused by uric acid and
calcium phosphate crystal deposition and usually develops
following cytotoxic chemotherapy. Here, we present a case
of spontaneous TLS in a patient with chronic myelomonocytic
leukaemia (CMML) with massive uric acid stone and
crystal formation and rapidly worsening renal failure. Autopsy revealed underlying tumourous kidney infiltration.
Risk factors for occurrence of TLS and current therapeutic
management are discussed.