Severe acute kidney injury with anuria induced by hypokalemia requiring hemodialysis: a case study

Background: Hypokalemia can result from various causes, with diarrhea being one of the most common. Although rare, chronic hypokalemia can lead to severe acute kidney injury (AKI) that requires dialysis. Therefore, this case study aims to investigate a patient with rectal cancer who, after concurrent chemoradiotherapy and ileostomy, developed chronic hypokalemia owing to prolonged diarrhea, leading to severe AKI with anuria. Case presentation: A 64-year-old man with a history of rectal cancer, ileostomy, and hypertension was admitted for severe AKI with anuria. He had developed severe hypokalemia due to chronic diarrhea. Despite having no prior kidney disease, his serum creatinine increased to 4.8 mg/dL, and potassium dropped to 2.2 mmol/L. Initial treatment included hemodialysis for anuric AKI with metabolic acidosis. A kidney biopsy revealed renal tubular vacuolization and With-no-lysine kinase (WNK) bodies in the distal tubules, which are characteristic of hypokalemic nephropathy. Potassium replacement therapy led to a gradual recovery of potassium levels and kidney function. Conclusion: This case highlights the importance of timely diagnosis and management of hypokalemic nephropathy through kidney biopsy.