An unusual case of acute kidney injury caused by oxalic acid mistaken for common salt

Abstract

Accidental exposure to chemicals and toxins is an important cause of acute kidney injury in the tropics. We report a case of a 26-year-old female who presented with acute kidney injury following a history of accidental ingestion of some white powder mistaken for table salt. Urine microscopy revealed the presence of calcium oxalate crystals. Because accidental poisoning was suspected despite normal 24-h oxalate excretion, renal biopsy was performed, which showed acute tubular injury with occasional refractile oxalate crystals. The patient improved symptomatically with conservative management and did not require haemodialysis. Subsequently, renal functioning showed an improving trend. Oxalic acid poisoning is relatively rare but is an emerging sporadic as well as epidemic poison in some regions.