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Published on: December 22, 2014
[Richner-Hanhart's syndrome or oculo-cutaneous tyrosinosis (about one case) (author's transl)]
Abstract:
Richner-Hanhart's syndrome correspond to an hypertyrosinemia due to a deficiency of a soluble tyrosine amino-transferase. This recently described tyrosinosis has been called oculo-cutaneous tyrosinosis. This disease transmitted on a recessive way in amenable to a treatment by a low tyrosine diet. In an infant, 18 months old, presenting a bilateral dendritic keratitis, a punctiform keratosis of the extremities, a patchy leucokeratosis of the tongue and a mental ketardation, the hypertyrosinemia reached 52 mg per 100 ml and the urine demonstrated the presence of phenyl-atonic acids. There was no hepato-renal involvement. The deferency of soluble amino-transferase was studied on the hepatocytes and confirmed. The low tyrosine diet made the clinical and biological signs disappear. The improvement was noticeable from the first week on and continued during the 16 months of the follow-up. There was no ill effect of the special diet on the weight and height growth. The oculo-cutaneous tyrosinosis is similar to the experimental form obtained by Schweizer on the rat. The occurrence of intracellular tyrosine crystals probably damages lysosine membrane and the release lysomie proteases induce the cellular lesions.
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