Bartter syndrome (BS) is a rare genetic disorder caused by a defect in the renal chloride-absorption mechanism in the thick ascending limb of the loop of Henle (TALH) . BS can be classified by age of presentation and severity as either antenatal/neonatal BS (ABS), which presents with severe, sometimes life-threatening disease in the fetus or newborn, or Classical BS, which is less severe and typically presents later in childhood or beyond.
BS can present in similar fashion with defects in any one of the three TALH channels involved in the sodium-chloride renal tubular reabsorption mechanisms. There are five known genes that define five types of BS.
Antenatal type I Bartter syndrome (ABS) is usually identified by the presence of polyhydramnios, premature delivery, hypokalemia, metabolic alkalosis, hypercalciuria, hyperprostaglandin E2 and nephrocalcinosis caused by mutations in the Na-K-2Cl cotransporter (NKCC2)-encoding SLC12A1 gene.
We describe a novel presentation of this syndrome with hypercalcemic hypercalciuric hyperparathyroidism, and review the literature of the variable atypical presentations of ABS.
