Abstract: Ｏｂｊｅｃｔｉｖｅ：To investigate clinicopathological features and prognosis of patients with acute phosphate nephropathy (APN) caused by oral sodium phosphate salts.
Ｍｅｔｈｏｄｏｌｏｇｙ：We retrospectively analyzed patients diagnosed with APN by renal biopsy at the National Clinical Research Center of Kidney Diseases, Jinling Hospital from January 2010 to November 2022, and analyzed their clinical manifestations, pathological features, treatment and prognosis.
Ｒｅｓｕｌｔｓ：A total of 9 patients with APN, including 7 males, aged 6011±914 years at the time of renal biopsy, were included. The patients were all taking oral sodium phosphate for the need of colonoscopy, and the serum creatinine (SCr) levels were in the normal range, but with a median presence of 3 highrisk factors. At the time of diagnosis of acute kidney injury (AKI), SCr was 25724±6365 μmol／L; except for one case with elevated blood phosphorus, the rest of the patients had normal blood calcium and phosphorus. Urinalysis was free of erythrocytes, and only 2 cases showed a small amount of proteinuria. Six patients were treated with prednisone (15~30 mg／d). At a median followup of 14 months, renal function improved in 7 patients, but none of the SCr returned to the normal range. SCr at the last followup was 17592±4505 μmol／L and the mean eGFR was 3633±1283 ml／(min·173 m2).
Ｃｏｎｃｌｕｓｉｏｎ：APN due to oral sodium phosphate salts usually has an insidious onset, and renal biopsy can help clarify the diagnosis. Phosphate lavage should be used with caution in patients with highrisk factors, and changes in renal function should be monitored closely for early recognition and management.

Key words: oral sodium phosphate, acute phosphate nephropathy, calcium phosphate