citrullinemia
Pronunciation: sit-rule-in-EE-me-ah
Inherited urea cycle disorder causing accumulation of citrulline and ammonia.
Full Definition
An autosomal recessive disorder of the urea cycle caused by deficiency of argininosuccinate synthetase (Type I) or citrin transporter (Type II). The condition leads to hyperammonemia and elevated citrulline levels, which can cause severe neurological damage or death if untreated. Newborn screening detects elevated citrulline in dried blood spots. Type I typically presents in the neonatal period with feeding difficulties, lethargy, and hyperammonemia, while Type II may have later onset. Treatment includes protein restriction, ammonia scavenger medications, and emergency protocols for hyperammonemic episodes.
Usage
Usage note: Specify type (I or II) when known; type I is more common in newborn screening detection.
In Context
- "Markedly elevated citrulline levels indicated citrullinemia requiring immediate ammonia assessment." — Critical result notification
- "Citrullinemia type II may not manifest until adulthood despite abnormal newborn screening results." — Clinical genetics consultation