Continuous hemodiafiltration during chemotherapy for acute kidney injury in spontaneous tumor lysis syndrome due to high-grade B-cell lymphoma: a case report.

Tumor lysis syndrome (TLS) is a life-threatening oncological emergency, characterized by hyperuricemia, electrolyte abnormality, and acute kidney injury (AKI). TLS usually occurs during chemotherapy, but rarely occurs before chemotherapy as spontaneous TLS (STLS). We describe a 54-year-old man who showed general fatigue. Laboratory tests showed myeloblasts in peripheral blood, marked elevations of serum uric acid (67.9 mg/dL), hyperphosphatemia, and severe renal dysfunction. Bone marrow biopsy findings were compatible with high-grade B-cell lymphoma (HGBCL). The patient was diagnosed with AKI in STLS caused by HGBCL, and hemodialysis was initiated on hospital day 2. However, hyperuricemia and anuria persisted. Chemotherapy was required. Therefore, continuous hemodiafiltration (CHDF) was performed instead of intermittent dialysis from hospital day 9 alongside chemotherapy. Rasburicase was given once on hospital day 12. After five days, serum uric acid and creatinine levels improved, and urine output increased, allowing discontinuation of CHDF. No adverse effects of chemotherapy, aggravated renal dysfunction, or TLS relapse were detected. Unfortunately, the patient died of alveolar hemorrhage on hospital day 61, despite normal renal function. In this case, AKI in STLS hindered prompt decision-making for chemotherapy because of concerns about further renal disorders after initiating chemotherapy. Switching to CHDF to sustainably correct hyperuricemia and electrolyte abnormalities resulted in favorable renal outcomes without complications. Although evidence regarding the efficacy of CHDF against TLS-induced AKI remains very limited, we suggest that management with CHDF for AKI in STLS or TLS is reasonable to prevent TLS aggravation during chemotherapy and to avert renal toxicity from the chemotherapy itself.