All of the following are features of Lesch-Nyhan syndrome EXCEPT:
Ans. (d) ImmunodeficiencyRef: Harper's Biochemistry, 30th edn. pg. 354-355* Lesch-Nyhan syndrome is a rare inherited disorder caused by a deficiency of the enzyme hypoxanthine- guanine phosphoribosyl transferase (HGPRT), produced by mutations in the HPRT gene located on X chromosome.Clinical Features* One of the first symptoms of the disease is the presence of sand-like crystals of uric acid in the diapers of the affected infant. Overproduction of uric acid may lead to the development of uric acid crystals or stones in the kidneys, ureters, or bladder. Such crystals deposited in joints later in the disease may produce gout-like arthritis, with swelling and tenderness* Irritability is most often noticed along with the first signs of nervous system impairment. Within the first few years of life, extrapyramidal involvement causes abnormal involuntary muscle contractions such as dystonia, atheotosis and opisthotonus.* Cognitive impairment: Affected persons have behavioral disturbances that emerge between 2-3 years of age. The self-injury begins with biting of the lips and tongue at the age of 3 years.Remember* A less severe related disease is partial HGPRT deficiency is known as Kelley-Seegmiller Syndrome (Lesch-Nyhan Syndrome involves total HGPRT deficiency). Symptoms generally involve less neurological involvement but the disease still causes gout and kidney stones.* The prognosis for individuals with severe LNS is poor. Death is usually due to renal failure or complications from hypotonia (PNEUMONIA), in the first or second decade of life.
Hyperuricaemia
Self-mutilation
Mental retardation
Immunodeficiency
Proteins and Amino Acids