Primary biliary cirrhosis with refractory hypokalemia: A case report.

Renal tubular acidosis (RTA) represents a class of metabolic disorders characterized by metabolic acidosis with a normal plasma anion gap. As a rare complication of primary biliary cirrhosis (PBC), RTA is easily overlooked, likely leading to misdiagnosis.A 32-year-old woman who had been diagnosed with PBC at our hospital was found to have hypokalemia due to repeated fatigue for 2 years, and the etiology was unknown.Due to the laboratory test results, radiographic findings, and pathologic results, she was diagnosed with PBC associated with RTA.She was then treated with ursodeoxycholic acid, potassium citrate, and calcium supplements together with activated vitamin D.Thus far, the patient showed a good response to ursodeoxycholic acid, and the clinical symptoms and liver function were significantly improved.Physicians that encounter refractory hypokalemia in a patient with PBC should be aware of the presence of RTA. The early diagnosis and treatment of such patients are of paramount importance to alleviate clinical symptoms and delay disease progression.