Acquired autoimmune Bartter syndrome in a patient with primary hypothyroidism

Abstract

We describe an unusual clinical presentation of autoimmune Bartter syndrome in a patient with primary hypothyroidism. A 65-year-old female patient was admitted with neuromuscular weakness associated with hypokalemia and metabolic alkalosis. She had a suboptimal response to potassium supplementation and potassium-sparing diuretic resulting in re-hospitalization with the same symptoms. A detailed serum and urinary biochemistry analysis in the absence of other causes of potassium wasting helped diagnose Bartter syndrome, a rare entity in adults. An autoimmune profile showed anti-Scl-70 antibody to be positive, although she did not develop other systemic features of the disease. Our patient responded to a steroid-based regimen potassium supplement, Indomethacin, and aldosterone antagonist with remarkable resolution of symptoms and correction of electrolyte derangement. We reviewed the literature to search for similar cases and included twenty-seven fulllength publications on acquired and autoimmune causes of Bartter syndrome. Our case highlights the fact that hypokalemia with metabolic alkalosis in an adult patient should prompt clinicians to evaluate for common and uncommon conditions. While assessing for abnormal conditions, acquired Bartter syndrome should be considered if a patient has an underlying autoimmune, endocrine, or connective tissue disease.

Secondary distal renal tubular acidosis and sclerotic metabolic bone disease in seronegative spondyloarthropathy

“…Circulating autoantibodies against CaSR have been found in autoimmune hypoparathyroidism and also in SS 28 29. Acquired Bartter’s syndrome due to circulating autoantibodies against one or more channels located in the thick ascending limb of loop of Henle is well established 30 31. Individuals with dRTA frequently demonstrate biochemical features of secondary hyperparathyroidism.…”