Abstract

SYSTEMATIC REVIEW OF LESCH-NYHAN SYNDROME

Sreethu Periyadath*, Akhila P. and Bincy Vargheese

ABSTRACT

Lesch-Nyhan syndrome(LNS) is a rare inborn error of purine metabolism, passed down as an X-linked, or sex-linked trait. People with this syndrome are missing or severely lacking an enzyme called hypoxanthine guanine phosphoribosyltransferase 1 (HPRT). The body needs this substance to metabolize uric acid. Without this enzyme, uric acid builds up in the central nervous system, kidneys, and other areas of the body. The three main features of the disease are Excessive production of uric acid, Neurological problems and Behavioural disorders. The first symptom of Lesch-Nyhan syndrome may be orange-colored crystal-like deposits, caused by increased uric acid in the urine. The diagnosis of LNS may be confirmed by a thorough clinical evaluation, including a detailed patient history and specialized blood tests. Children with this disorder have abnormally high concentrations of uric acid in the blood. The absence of the enzyme HPRT in cells from any tissue confirms the diagnosis. Carrier testing is possible using molecular genetic testing. Prenatal diagnosis and preimplantation genetic diagnosis are possible if the disease-causing HPRT1 gene mutation has been identified in an affected family member. Prenatal diagnosis can also be done by enzyme analysis. No specific treatment exists for Lesch-Nyhan syndrome. Gout can be treated with allopurinol, reduces uric acid levels. However, treatment does not improve the neurological outcome. Few treatments have proven consistently helpful for the neurologic or behavioral difficulties. Behavioral abnormalities are best managed by a combination of behavioral modification techniques and medications.

Keywords: Lesch–Nyhan syndrome (LNS), hypoxanthine guanine phosphoribosyltransferase 1 (HPRT), uric acid, orange sand, gene mutaton.