Lesch–Nyhan Syndrome

Lesch–Nyhan syndrome is a rare, X-linked metabolic disorder caused by mutations in HPRT1, an important gene that codes for the hypoxanthine-guanine phosphoribosyltransferase (HGPRT) enzyme in the purine salvage pathway. Affected individuals can have symptoms including hyperuricemia, intellectual disability, motor impairment including dystonia, and in severe cases, self-mutilation. The diagnosis is established either with genetic analysis, or HGPRT enzyme assay. Psychiatric treatment is often necessary in this population for severe self-mutilation, though may also be requested for cognitive impairment, anxiety, emotional lability, and attention problems. Common treatments for self-mutilation include restraints, protective equipment, dental guards, and dental extraction, as well as pharmacologic management. Psychiatric treatments must be tailored to the known medical comorbidities associated with Lesch–Nyhan syndrome including hyperuricemia with potential subsequent renal impairment, and motor impairments involving the extrapyramidal system.