disease has basis in dysfunction of HPRT1 hypoxanthine guanine phosphoribosyltransferase partial deficiency HPRT deficiency, grade I HPRT deficiency, partial HPRT partial deficiency HPRT-related gout HPRT-related hyperuricemia HPRT1 partial deficiency Hprt1 deficiency, partial ICD10:E79.8 ICD9:277.2 KELLEY-Seegmiller syndrome Kelley-Seegmiller syndrome Kelley-Seegmiller syndrome (KSS) is the mildest form of hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency, a hereditary disorder of purine metabolism, and is associated with uric acid overproduction (UAO) leading to urolithiasis, and early-onset gout. MESH:C562583 MONDO:0010299 OMIM:300323 Orphanet:79233 SCTID:238007004 UMLS:C0268117 gout, HPRT-related hypoxanthine guanine phosphoribosyltransferase 1 deficiency, partial hypoxanthine guanine phosphoribosyltransferase 1 partial deficiency hypoxanthine guanine phosphoribosyltransferase deficiency, grade I hypoxanthine-guanine phosphoribosyltransferase deficiency