A rare presentation of methanol toxicity
A 51-year-old male presented with abdominal pain, nausea, and vomiting for 1 day with altered mentation, decreased urine output, and sudden onset blurring of vision since 12 h. The patient was a chronic alcoholic and smoker for last 10 years and there was history of consumption of unquantified amount of country liquor 1 day back. There was no history of fever, blood in urine, seizures, weakness, decreased sensations, or bowel disturbances. Other history was not significant. On examination, the patient was conscious but confused. His vitals were normal. General physical examination revealed mild pallor. On central nervous system examination, the Glasgow coma scale was E4M5V3; there was diminished light perception in both the eyes; pupils were normal sized bilaterally but sluggishly reacting to light. Other cranial nerves were normal. There was no motor or sensory deficit. Cerebellar signs like finger nose test, dysdiadochokinesis, and heel-shin tests were abnormal on the right side. The patient had a wide based gait. Rest of his examination was normal. His complete blood count and liver function tests at the time of presentation were normal. Random blood sugar was 6.1 mmol/L. Kidney function tests showed blood urea nitrogen of 27 mmol/L, creatinine of 238 mmol/L, serum sodium 146 mmol/L, and potassium 4.2 mmol/L. Arterial blood gas revealed pH of 7.21, bicarbonate of 10 mmol/L, paCo2 of 18 mm Hg. With clinical possibility of methanol toxicity, serum osmolar gap was calculated. It was found to be 74; serum methanol levels were sent which were high with value of 8.04 mmol/L. Magnetic resonance (MR) imaging of the brain revealed hemorrhagic conversion of infarct in bilateral parasagittal, parieto-occipital region. An acute infarct was seen in right cerebellum. There were punctate infarcts in bilateral frontal regions [Figures and ]. Visual-evoked response revealed prolonged bilateral (R > L) P100 and bilateral (R>>L) demylination of optic nerve. Serum levels of ammonia, vitamin B12, folate, amylase, and lipase were normal. The ultrasonography of the abdomen and the thyroid function tests were normal. In view of methanol poisoning, hemodialysis was done and ethanol was given through the naso-gastric tube since the patient could not afford fomepizole. The patient responded to treatment. Patient’s visual acuity improved. Initially at presentation, it was finger-counting (FC+) at 1 m. Now the patient has visual acuity of 6/36 in both eyes without visual aids with minimal focal neurologic deficit and is on regular follow-up.