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Ornithine transcarbamylase deficiency

What is Ornithine Transcarbamylase Deficiency (OTC) ?

Ornithine Transcarbamylase Deficiency (OTC) is a serious and potentially life threatening metabolic disorder, under the general category of "Urea Cycle Disorders". This is a condition in which the handling of protein and its breakdown leads to a rise in Ammonia which without the appropriate treatment, can lead to significant morbidity and mortality.

Ornithine transcarbamylase deficiency is an inherited disorder that often shows symptoms in the first few days of life, normally if boy’s aren’t diagnosed very early on it is likely they will die sadly (wrongly being put down to cot death or suspected meningitis ) because they do not have another X gene to compensate where girls may survive untreated longer although at extreme risk of significant morbidity and mortality if their affected X is located within the liver.

An infant with OTC may be lethargic or unwilling to eat, vomiting more then usual infants and have poor breathing rate or body temperature. Some babies with this disorder may experience seizures, or go into a coma. Complications from ornithine transcarbamylase deficiency may include developmental delay and intellectual disability, liver damage, skin lesions, brittle hair.

In some affected individuals which is extremely likely to be girls, signs and symptoms of ornithine transcarbamylase may not appear until later in life but have a history of Vomiting, hallucinating, Lethargy, being very fussy eaters (which is them unknowingly restricting there protein) may be pale skinned and have been admitted a lot to hospital only to be sent home with a wrong diagnosis for there symptoms, many affected by Urea Cycle Disorders also have a diagnosis of autism. if the condition is undiagnosed and untreated, hyperammonemic coma or death may occur. If an undiagnosed affected women later in life has had very few symptoms it’s likely the good X as well as the Bad X is within their liver compensating but undiagnosed and untreated, hyperammonemic coma or death may still occur .


On the left is a video of such an inspirational little girl called Alyssa who has OTC deficiency but wasn’t diagnosed until she was 8 years old when the condition almost killed her, doctors said at the time she was going to die but she managed to survive despite the odds but sadly has been left with a catastrophic brain injury.

When Alyssa was born she was in the Special Care Baby Unit for 4 days with Hypothermia and Vomiting, As a baby she vomited a lot and was taken into hospital a few times, the parents were sent home and told to just syringe her water, consultants said she just had a dairy intolerance and to use soya milk to feed her with, Alyssa was delayed with speech and did echolalia around the age of 3 year, her parents were told by the consultant Alyssa was under that she had global developmental delay, she then went on to be diagnosed with Autism, Alyssa’s vomiting become less often once she was off formula and choosing her own foods although vomiting was still an issue (being a very picky eater) her speech improved although it was typically autistic.

On occasions Alyssa hallucinated and become almost feral, the local doctors said it was just a lack of glucose so parents gave her lucozade which seem to return her to her normal self, Alyssa was doing well until 6 Months before her brain injury, she hallucinated, become delusional and very floppy, she was admitted to her local hospital and treated for suspected meningitis, once well she was discharged home again.

6 months later she got the norovirus, at first she vomited a lot but soon become delusional and very floppy and again returned to hospital, only this time she almost died, One doctor did an Ammonia blood test which come back very high so treated her for OTC, unfortunately the Ammonia had already done incredible damage to Alyssa’s brain and once in London was only given 72 hours to live.

Metabolic awareness can save lives, Alyssa clearly showed symptoms throughout her life which sadly doctors failed to diagnose correctly, Alyssa would have never nearly died or suffered a terrible brain injury which has greatly impacted her life if she was diagnosed correctly, Through Alyssa's story we hope that we can create Metabolic awareness.


I think I may have Ornithine Transcarbamylase Deficiency (OTC) who do I Contact?.

If you recognise any symptoms of Ornithine Transcarbamylase Deficiency (OTC] within yourself or your child you should contact your Local GP immediately for a referral to see a inherited metabolic diseases specialist. See Resources for more information.