eMedicine Specialties > Pediatrics: Genetics and Metabolic Disease > Metabolic Diseases
Citrullinemia: Follow-up
Updated: Mar 26, 2009
Follow-up
Further Outpatient Care
- Patients with citrullinemia must be under the ongoing care of a biochemical geneticist or metabolic disease specialist with expertise in the care of urea cycle disorders.
- A trained nutritionist should monitor the low-protein diet, which is essential in treatment.
- Frequent monitoring of growth and blood amino acid levels is imperative in order to make adjustments before essential amino acid levels fall below normal and the child becomes catabolic.
- Under no circumstances should a primary care provider provide follow-up for a patient with citrullinemia without the frequent input of a specialist.
Transfer
- Any infant or child noted to have hyperammonemia should be considered for transfer to a medical center for further evaluation.
Deterrence/Prevention
- Prenatal diagnosis is possible and is available at academic centers. Molecular diagnosis is possible, using amniocytes or chorionic villi.
Complications
- Complications are chiefly neurological, including mental retardation, acute hyperammonemic coma, and death.
Prognosis
- Consistent with the course of most urea cycle disorders, the degree of intellectual impairment is roughly parallel to the severity of initial presentation and frequency of subsequent hyperammonemic episodes. Subsequent hyperammonemic episodes predictably recur with any intercurrent infection.
- With appropriate treatment, survival into adulthood is possible and has been documented.
Patient Education
- Both parents of an affected infant are assumed to be obligate heterozygotes because citrullinemia is an autosomal recessive trait; therefore, the recurrence rate in every subsequent pregnancy is 1 in 4, or 25%.
- Genetic counseling is indicated.
- Advise the parents to seek early medical care for the affected child at the earliest signs of infection.
- Counsel the parents regarding strict adherence to the prescribed medical regimen.
- Prenatal diagnosis is theoretically available, although it is not trivial.
Miscellaneous
Medicolegal Pitfalls
- Suspect hyperammonemia in all infants and children with unexplained neurologically related symptoms and signs. Failure to do so may result in missed diagnosis of a treatable disorder.
- Failure to establish a diagnosis in a proband may result in subsequent infants in the family with the same disease.
Special Concerns
- Adults with hepatic cirrhosis unassociated with most common causes, such as long-term alcohol consumption, should be evaluated for the adult-onset form of citrullinemia.
- This condition has been most frequently reported in Japan and was initially described in that country, probably leading to a heightened clinical awareness not shared in the United States. Thus, the disorder could be significantly more common than originally believed.
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| Treatment & Medication: Citrullinemia |
Follow-up: Citrullinemia |
| Multimedia: Citrullinemia |
| References |
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References
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Further Reading
Keywords
citrullinemia, citrulline, argininosuccinic acid synthase deficiency, citrullinuria, aminoaciduria, ornithine transcarbamylase reaction, argininosuccinic acid, ASA, ASA synthase, carbamyl phosphate synthetase reaction, CPS reaction, waste nitrogen disposal, hyperammonemia, mental retardation, urea cycle defect, neonatal intrahepatic cholestasis, NICCD, hepatomegaly, treatment, diagnosis
Follow-up: Citrullinemia