A rare case of cumulative methanol poisoning caused vision loss after 14 days

نویسندگان

1 Toxicological Research Center, Excellence Center of Clinical Toxicology, Department of Clinical Toxicology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Toxicological Research Center, Excellence Center of Clinical Toxicology, Department of Clinical Toxicology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

3 Toxicological Research Center, Excellence Center of Clinical Toxicology, Department of Clinical Toxicology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

4 School of Medicine, Islamic Azad University, Tehran, Iran

5 Toxicological Research Center, Excellence Center of Clinical Toxicology, Department of Clinical Toxicology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

doi
10.22038/apjmt.2024.80269.1458
چکیده

Background: The following case report discusses a person who experienced vision loss after consuming a homemade alcoholic beverage for 14 days.Case presentation: A 32-year-old Iranian man with a chief complaint of blindness was referred to Loghman Hakim Hospital.Results: The patient's visual acuity was limited to light perception, meaning he could only identify the direction of the light. He had a history of purchasing a 20-liter batch of homemade alcoholic beverages, which he consumed over 14 days with various groups of friends. The day after he finished the drink and stopped consuming it, his vision started to deteriorate. By the end of the second day, he was nearly blind. None of his other friends who drank from the same alcohol were showing any visual or other symptoms of methanol poisoning problems. The liquor he purchased contained a small amount of methanol. While folinic acid detoxified it in his friends, it accumulated in him over two weeks of constant drinking. Because ethanol is a competitive inhibitor of methanol for the alcohol dehydrogenase (ADH) enzyme, the methanol was not converted.Discussion: Methanol toxicity, a leading cause of blindness in developing nations, damages the optic nerve and retina by disrupting mitochondrial function through formic acid’s effect on cytochrome oxidase. ADH isoenzyme variations affect methanol elimination rates and delayed neurological syndromes, including vision problems.Conclusion: Formic acid led to blindness. However, as his blood ethanol levels decreased, he began showing symptoms of methanol toxicity.