title: Clinical and Biochemical Profile of Tyrosinemia Type 1 in Tunisia.
abstract: BACKGROUND
  Hereditary tyrosinemia type 1 (HT1) is an autosomal recessive disease caused by a defect of fumarylacetoacetate hydrolase. This study aimed to estimate the prevalence of HT1 in Tunisia and report its clinical, biochemical and genetic features.
  
  
  METHODS
  During the last 25 years, 69 patients were diagnosed with HT1 based on clinical features and increased succinylacetone (SA) in blood and urine. SA was detected by GC-MS after oximation and quantified by a spectrophotometric method. Nine prenatal diagnoses for HT1 have been done and nine unrelated patients were screened for the hotspot IVS6-1(G-T) mutation using PCR.
  
  
  RESULTS
  Using the Hardy-Weinberg formula, the incidence of HT1 was estimated at 1/14804 births in Tunisia. According to clinical form, 21 patients (30%) had the acute form and 48 patients (70%) had the chronic form. Mean plasma and urine SA were higher in the acute form (24 and 193 μmol/L vs. 9 and 90 μmol/L, respectively). Diagnosis of HT1 was done for 4 fetuses. The hotspot IVS6-1(G-T) mutation was found in six of nine explored patients.
  
  
  CONCLUSIONS
  The incidence of HT1 is relatively high in Tunisia with a predominance of the chronic form. It is important to diagnose the disease as early as possible to prevent unfavorable issues. Prenatal diagnosis should be recommended to minimize the recurrence of the disease.
authors.forename: Fahmi
authors.initials: F
authors.lastname: Nasrallah
authors.forename: Mohamed Bessem
authors.initials: MB
authors.lastname: Hammami
authors.forename: Hanen
authors.initials: H
authors.lastname: Ben Rhouma
authors.forename: Sondes Hadj
authors.initials: SH
authors.lastname: Fradj
authors.forename: Hatem
authors.initials: H
authors.lastname: Azzouz
authors.forename: Souheil
authors.initials: S
authors.lastname: Omar
authors.forename: Moncef
authors.initials: M
authors.lastname: Feki
authors.forename: Ilhem Turki
authors.initials: IT
authors.lastname: Ben Youssef
authors.forename: Taieb
authors.initials: T
authors.lastname: Messaoud
authors.forename: Neji
authors.initials: N
authors.lastname: Tebib
authors.forename: Naziha
authors.initials: N
authors.lastname: Kaabachi
mesh_terms: D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D011247:Pregnancy; D015995:Prevalence; D014416:Tunisia / Q000453:epidemiology; D020176:Tyrosinemias / Q000097:blood / Q000453:epidemiology* / Q000235:genetics