Ornithine aminotransferase deficiency
| Ornithine aminotransferase deficiency | |
|---|---|
| Other names | Gyrate atrophy (of the choroid and retina) |
 | |
| Ornithine | |
| Specialty | Ophthalmology, medical genetics  |
Ornithine aminotransferase deficiency (also known as gyrate atrophy of the choroid and retina) is an inborn error of
Research suggests there can be some adverse effect on muscles and also the brain. The cause of this is somewhat unclear but may relate to very low levels of creatine often found in this population.
Treatment may include vitamin B6, lysine or dramatic dietary change to minimise arginine from patients diet. Research has indicated that these treatments may be somewhat effective in lowering ornithine blood concentration levels in some patients, either in combination or individually. Vitamin B6 has been found to be very effective in a small proportion of patients.
Presentation
Quite often, the presenting symptom of ornithine aminotransferase (OAT) deficiency is
In some cases, affected individuals will present in the neonatal period with disease that closely mimics a classic urea cycle defect, such as ornithine transcarbamylase deficiency, as the block in ornithine metabolism leads to secondary dysfunction of the urea cycle. These individuals present with hyperammonemia, poor feeding, failure to thrive and increased excretion of orotic acid.[3]
Genetics
OAT deficiency is inherited in an
Diagnosis
Upon clinical suspicion, diagnostic testing will often consist of measurement of
Treatment
To reduce the levels of ornithine in the blood, a diet restricted in arginine has been used.[2] Some research has shown that when diet or other treatment is initiated early in life, the outcome can be improved.[2]
References
- ^ "Gyrate atrophy of the choroid and retina". National Institutes of Health. Retrieved 2012-08-23.
- ^ a b c d e "#288870 - Gyrate atrophy of the choroid and retina". Johns Hopkins University. Retrieved 2012-08-23.
- ^ ISBN 978-3-642-15719-6.