Skip to
  1. Homepage
  2. Rare diseases
  3. Search
Simple search

Simple search

(*) mandatory field


Other search option(s)

Argininosuccinic aciduria

Synonym(s) Argininosuccinase deficiency
Prevalence 1-9 / 1 000 000
Inheritance Autosomal recessive
Age of onset Childhood
  • E72.2
  • C0268547
  • D056807
  • 10058299


Arginosuccinicaciduria is an autosomal recessive inherited deficiency of arginosuccinate lyase, an enzyme involved in the urea cycle. This leads to hyperammonemia and arginine deficiency. Onset occurs either soon after birth, with severe hyperammonemic coma that often proves to be fatal, or during childhood, with hypotonia, growth failure, anorexia and chronic vomiting or behavioral disorders. Onset can also occur later with hyperammonemic coma or behavioral disorders that simulate psychiatric disorders. Significant hepatomegaly and trichorrhexix nodosa are common observations. Diagnosis is made by the existence of hyperammonemia and by chromatography of plasmatic and urinary organic acids that shows accumulation of arginosuccinic acid (ASA) and orotic aciduria. Patients are treated with a strict lifelong diet with very low amounts of protein intake, arginine supplementation, and sometimes sodium benzoate or sodium phenylbutyrate. Antenatal diagnosis can be performed either by direct measure of citrulline and ASA in amniotic fluid or by enzymatic assay

Expert reviewer(s)

  • Pr Jean-Marie SAUDUBRAY

(*) Required fields.

Attention: Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image

Detailed information

Emergency guidelines
  • EN (2012,pdf)
Clinical practice guidelines
  • EN (2012)
Article for general public
  • NL (2011,pdf)
  • ES (2011,pdf)
  • FR (2011,pdf)
  • IT (2011,pdf)
  • PT (2011,pdf)
  • DE (2011,pdf)
  • EN (2013)
Clinical genetics review
  • EN (2012)
Get Acrobat Reader
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.