- Richner Hanhart syndrome
Richner Hanhart syndrome, also called Richner syndrome or Hanhart syndrome, [Hanhart E (1950) "Über die Kombination von Peromelia mit Mikrognathia, ein neues Syndrom beim Menschen, entsprechend der Akroteriasis congenita von Wriedt und Mohr beim Rinde". Archiv der Julius Klaus-Stiftung für Vererbungsforschung, Sozialanthropologie und Rassenhygiene, Zürich. 25: 531-544.] is a rare
autosomal recessive disorder due to a deficiency of theenzyme tyrosine aminotransferase .ymptoms
Symptoms of Richner Hanhart syndrome include ocular
lesion s and palmo-plantarhyperkeratosis . Eye symptoms develop from two weeks of age and include redness,lacrimation andphotophobia . Tyrosine crystals in thecornea causecornea l clouding with corneal opacities, corneal scarring and dendritic ulcers. In the first year of life, the patient will show skin conditions like nonpruritic hyperkeratotic papules and plaques on the palms and soles.Mental retardation affects less than 50% of all cases. Patients will have high levels oftyrosine in the urine.Pathophysiology
Richner Hanhart syndrome is caused by a deficiency of the enzyme tyrosine amino transferase (TAT). TAT is located on
chromosome 16 q22.1-q 22.3.Treatment
Dietary restriction of
amino acid sphenylalanine andtyrosine is an effective treatment for people with Richner Hanhart Syndrome.Eponym
It is named for Ernst Hanhart and Hermann Richner, who independently reported it in
1947 and1938 , respectively.References
External links
*http://medind.nic.in/icb/t06/i2/icbt06i2p161.pdf#search=%22richner%20hanhart%20syndrome%22
*OMIM3|276600 RareDiseases|3105|Tyrosine transaminase deficiency; Richner-Hanhart syndrome
*cite web |url=http://www.ghr.nlm.nih.gov/condition=tyrosinemia |title=Tyrosinemia |format= |work=Genetics Home Reference |accessdate=
*cite web |url=http://www.orpha.net/consor/cgi-bin/OC_Exp.php?Lng=EN&Expert=28378 |title=Tyrosinemia type 2 |format= |work=Orphanet |accessdate=
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