Adenylosuccinase deficiency: clinical and biochemical findings in 5 Czech patients.

Abstract

Adenylosuccinase deficiency (McKusick 103050) is a genetic defect of purine nucleotide metabolism discovered in 1984 (Jaeken and Van den Berghe 1984). Adenylosuccinase (adenylosuccinate lyase, ASase, EC 4.3.2.2) catalyses the reaction in the de novo synthetic pathway and also the formation of adenosine monophosphate (AMP) from adenylosuccinate (S-AMP). The disorder is characterized by an accumulation of succinylaminoimidazole carboxamide riboside (SAICAR) and succinyladenosine (S-Ado) in body fluids, particularly in cerebrospinal fluid and urine. Psychomotor retardation is the principal symptom of the disorder. The majority of the children described also have epilepsy. Some patients display in addition agitation, involuntary movements, hypotonia, autistic features, growth failure and muscle wasting (Jaeken et al 1988). Only 14 patients have been reported to date (Salerno et al 1995).