Rarest of the rare: OCD complicates metabolic disorder, a case report.

He asked his parents to hide the knives because he was afraid of hurting someone. The patient had a diagnosis of homocystinuria at the age of 16, with several complications like renal infarction, deep vein thrombosis, and retinal detachment. He was medicated with warfarin, and no specific diet was followed.family history was suggestive of history of bipolar 1 disorder in relatives.

MSE revealed anxious mood, preoccupation and prominent obsessive thoughts. All his investigations came normal except for high levels of homocysteine (821 μ mol/l). Brain magnetic resonance imaging (MRI) showed low T2 signal, microvascular ischemia in white matter of the right frontal lobe.

Patient was first given haloperidol 2mg tid because of agitation. Then, he started a low protein diet and a treatment with cyanocobalamin 0.2mg bid, pyridoxine 200mg bid, thiamine 100mg bid, and folic acid 5mg bid. After two weeks of treatment, the symptoms were practically absent. At the time he was discharged, he still had some thoughts and worries about his work and verification behaviour leading to him confirming if he had done anything wrong, but he was able to return to work.

Two weeks after discharge, he attended an appointment and he was asymptomatic. Haloperidol was progressively reduced until stopped in about two weeks. A month after inpatient discharge, his homocysteine levels were lower (362.9 μ mol/l), and he remained asymptomatic. The treatment was changed to pyridoxine 300 mg tid that lead to undetectable levels in a month (<15 μ mol/l).

He was followed during a year and maintained on a low protein diet and pyridoxine 300 mg tid. After this period, he was discharged from psychiatry consultation. This case underlines the importance for a psychiatrist to explore medical nonpsychiatric history, especially when presentation is abrupt, atypical, or in treatment-resistant cases.

Source: Hindawi journal: https://doi.org/10.1155/2021/5523453