Kelley-Seegmiller syndrome in a patient with complete hypoxanthine-guanine phosphoribosyltransferase deficiency.

Different degrees of hypoxanthine guanine phosphoribosyltransferase (HPRT) deficiency are associated with hyperuricemia, uric acid nephrolithiasis and severe gout. Up to 25-30% of HPRT deficient patients, indicated as neurological variants or HPRT-related hyperuricemia with neurological dysfunction (HRND), may develop neurological manifestation, from mild to severe; the most serious ones manifesting in the devastating Lesch-Nyhan syndrome, characterized by choreoathetosis or self-mutilation. Here we present a 30 years old male patient suffering from gout and mild psycho-motor impairment without Lesch Nyhan disease despite severe HPRT deficiency residual activity 0.02% with hypoxanthine, no activity at all with guanine as a substrate. The Curto's theory that neurologic impairment is dependent on VGPRT/VHPRT ratio is not confirmed by our observations. The finding of such a severe HPRT deficiency in a non-Lesch-Nyhan patient needs further investigation. G6PD deficiency was also referred together with beta-thalassemic trait. We have studied purine and pyridine nucleotide metabolism in the erythrocytes and discussed the literature. The bone marrow sample shows a megaloblastyc aspect.