A Case of Distal Renal Tubular Acidosis with Sjögren’s Syndrome Presenting as Hypokalemic Paralysis

Abstract

Distal renal tubular acidosis (RTA) caused by autoimmune nephritis occurs in up to 25% of patients with Sjögren’s syndrome. However, patients with hypokalemic paralysis are sometimes overlooked, because most symptoms of autoimmune nephritis in Sjögren’s syndrome are mild. We present a case of hypokalemic paralysis in a 54-year-old female who also had dry eyes and mouth, and Raynaud’s phenomenon. Further evaluation, including autoantibody tests, revealed distal RTA with Sjögren’s syndrome as the cause of hypokalemia. Distal RTA diagnosis was made based on normal anion gap hyperchloremic metabolic acidosis, alkaline urine with positive urine anion gap, high transtubular potassium concentration gradient (TTKG), positive anti-La antibody, and symptoms of sicca complex. The patient’s symptoms resolved following treatment with intravenous and oral potassium, immunosuppressants, and steroids. This case illustrates that distal RTA and Sjögren’s syndrome should be considered in cases of hypokalemic paralysis.