Late-onset ornithine transcarbamylase deficiency mimicking a focal opercular syndrome

Ornithine Transcarbamylase Deficiency Presenting as Acute Encephalopathy After Strabismus Surgery

Acute encephalopathy with an unclear etiology is a common presentation to the hospital. We describe the case of a 50-year-old male who presented with a one-day history of slurred speech, nausea, insomnia, and altered mental status. His surgical history was notable for a strabismus surgery two days ago. He presented with elevated ammonia levels that continued to increase. Metabolic studies were suggestive of hyperammonemia secondary to ornithine transcarbamylase (OTC) deficiency triggered due to fasting prior to the strabismus surgery. OTC gene sequencing confirmed the diagnosis of OTC deficiency. We summarize the current case reports in the literature and review the treatment options for OTC deficiency. Our case occurred after a low-risk outpatient strabismus surgery and is a good example of maintaining a broad differential and revising the suspected diagnosis constantly.