This Month’s Highlights

[摘要] Bartter syndrome is a recessive genetic disorder associated with reduced NaKCl2 co-transporter activity and is associated with severe salt wasting, usually in the perinatal period. In this issue of JASN, Pressler et al. describe two brothers who presented with hyperuricemia, metabolic alkalosis, hypokalemia, and bilateral medullary nephrocalcinosis at the age of 13 and 15 yr. Impaired NaCl reabsorption along the thick ascending limb was inferred from responsiveness to furosemide. Genetic analysis revealed that both boys were compound heterozygotes for mutations in the SLC12A1 gene coding for the NaKCl2 co-transporter. Functional analysis of these mutants in the Xenopus oocytes expression system revealed significant residual transport activity of the NKCC2 p.F177Y mutant and no activity for the NKCC2-D918fs frameshift mutant. However, co-expression of the two mutants was not significantly different from that of NKCC2-F177Y alone. The partial function of NKCC2-F177Y explains this mild, late-onset phenotype in these brothers and thereby expands the spectrum of Bartter syndrome. See Pressler et al., pages 2136–2142.

[学科分类] 泌尿医学

[关键词] Bone marrow necrosis;Sickle cell disease;Hyperhemolysis syndrome