A case of biopsy-proven oxaliplatin-induced acute tubulointerstitial nephritis with thrombocytopenia and anemia.

Oxaliplatin, a third-generation platinum agent, has been used for the treatment of colon, pancreatic, and stomach cancers in recent years. It carries a reduced risk of acute kidney injury (AKI) compared to the previous platinum agents, including cisplatin and carboplatin. Several cases of oxaliplatin-induced acute tubular necrosis (ATN) have been reported; however, only one case has been reported as acute tubulointerstitial nephritis (ATIN) histopathologically. Here, we present a case of biopsy-proven and dialysis-dependent ATIN, which dramatically resolved with steroid therapy. The patient was a 67-year-old male who had undergone chemotherapy for colon adenocarcinoma. He suddenly developed shaking chills, fever, and hot flashes at the end of the 18th 5-fluorouracil (5-FU)/L-leucovorin/oxaliplatin administration, and was admitted to our hospital. On the 4th day of hospitalization, severe renal dysfunction (creatinine 6.5 mg/dL) was observed. As oliguria continued, we initiated hemodialysis therapy on the 6th day of hospitalization. Drug-induced ATIN was strongly suspected due to the history of multiple exposures to oxaliplatin with allergic reaction and sterile pyuria. We began steroid therapy on the 8th day of hospitalization. Subsequently, renal biopsy was performed and the diagnosis of ATIN was made. The patient's renal function gradually improved, and 6 months later, it had returned to baseline. Our case demonstrates that we should consider not only ATN, but also ATIN, as potential presentations of oxaliplatin-induced AKI.