Clinical Case Scenario

A 22-year-old male with Burkitt lymphoma arrives at oncology day care with acute abdominal pain, nausea, vomiting, and confusion shortly after starting R-CODOX-M (rituximab, cyclophosphamide, vincristine, doxorubicin, and methotrexate). His vitals are BP 90/67 mmHg, HR 121/min, SpO2 95% on room air, and respiratory rate 25/min. Venous blood gas analysis shows: pH 7.23, PCO2 26 mmoL/L, HCO3 17 mmoL/L, Lactate 2.24 mmoL/L.

Laboratory tests reveal the following:

Despite initial aggressive intravenous fluid resuscitation and treatment with rasburicase, the patient's urine output has dropped significantly, and he is now anuric. Which of the following is the most likely complication this patient is experiencing?