Methanol poisoning in Turkey: Two outbreaks, a single center experience

Abstract

Objectives: Methanol poisoning is still one of the major causes of mortality due to intoxication because of the challenging diagnosis and late hospital admissions. We aimed to evaluate epidemiological data, clinical characteristics, laboratory findings, treatment protocols, and prognosis of patients in a tertiary hospital in two different methanol outbreaks occurring in a three-year interval.

Methods: The study was planned as a single-center and retrospective observational case series study. Patients ≥18 years of age who were admitted to the hospital between 1 September 2016 and 1 September 2019 and diagnosed with methanol poisoning were included in the study.

Results: Sixty-seven patients whose data were sufficient and accessible were included in the study. Thirty-five (52.2%) patients were discharged without sequelae, 14 (20.9%) patients were discharged with sequelae (both central nervous system sequelae and visual sequelae in 3 patients, only visual sequelae in 11 patients) and 18 (26.9%) patients died. High anion gap (AG) metabolic acidosis (pH < 7.07, AG > 26.7), low Glasgow Coma Score, and increased lactate (lactate > 2.55 mmol/L) levels were found to be associated with poor outcome. Folate use in treatment did not have a statistically significant effect (p = 0.087) on the prevention of visual sequelae development, but it had a statistically significant effect on mortality (p = 0.041).

Conclusions: State of consciousness and the severity of metabolic acidosis were significant parameters associated with mortality. In addition to antidote and elimination therapies, given the benefit on mortality and low risk of adverse events, folate therapy should be considered for all patients with significant toxic methanol exposures.

Keywords: anion gap; folate; lactate; metabolic acidosis; methanol poisoning; outcomes.