Diagnosis of Ornithine Transcarbamylase Deficiency during Pregnancy: Case Report

Background: Ornithine Transcarbamylase deficiency (OTCD) is the most common enzyme deficiency in the urea cycle. Despite being an X-linked disorder, heterozygous females can develop nonspecific and diverse symptoms. Here, a case of an OTCD diagnosis during early pregnancy in a female previously diagnosed with a psychiatric disease is described.
Case report: A 29-year-old female pregnant (G3) with a diagnosis of dissociative disorder, attributable to a deceased newborn of unknown cause as a trigger, enters the emergency room (ER) having a 1-week history of disorientation, aggressiveness, anorexia, and vomiting. An initial diagnosis of probable Wernicke encephalopathy prompted the use of thiamine and discharge from the ER. After a protein-rich meal, symptoms worsen, and the patient is readmitted to the ER in a stuporous state, progressing to a coma. At admission, the ammonia level was 294 umol/L, which suggested a potential OTCD. Hemodialysis was started, with an improvement in the neurological state. Gene sequencing of OTC confirmed OTCD (c.77+5G>A). Protein restriction and lactulose were maintained during the remainder of the pregnancy.
Discussion: This case highlights the relevance of OTCD as a differential diagnosis in women with psychiatric disorders and protein aversion, more so in a female with a history of a deceased newborn of unknown cause. OTCD management during pregnancy and postpartum is challenging, given the chance of more frequent decompensations.
Conclusion: This case highlights the relevance of OTCD as a differential diagnosis in women with psychiatric conditions.