When the kidneys speak for the brain: a nephrological presentation of a rare neurological disorder.

Lesch-Nyhan syndrome (LNS) is a rare X-linked recessive disorder caused by complete deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT). While the disease is classically characterized by severe neurological manifestations and self-injurious behavior, kidney involvement is an underrecognized but important aspect of the clinical spectrum.