Methanol and ethylene glycol poisoning. Study of 18 cases

BACKGROUND: The present study reviews acute intoxication by methanol and ethylenglycol analyzing its form of presentation, treatment applied and prognosis. METHODS: A retrospective study performed in 5 hospitals from the Barcelona area (Spain) from January 1984 to December 1993 is reported. RESULTS: Eighteen patients, 16 intoxicated by methanol and 2 by ethylenglycol were reviewed. The blood levels of methanol on admission ranged from 350 to 4,600 mg/l (mean = 1,649 +/- 1,220 mg/l). The clinical course was initially characterized by alteration of the level of consciousness (in 61% the index of Glasgow of coma was < or = 7) and development of metabolic acidosis (pH < or = 6.80 in 44% of cases). Eighty-seven percent of patients intoxicated by methanol had visual disorders. Treatment consisted in the administration of ethanol, bicarbonate and extrarenal exchange. Mortality was 44%, being greater among patients with the lowest initial pH (p = 0.0001) and with the lowest concentration of bicarbonates (p < 0.03). The patients with lower pH (r2 = 0.65, p < 0.002) and with a lower value of blood bicarbonate (r2 = 0.87; p < 0.0001) on admission were significantly more severe. Sequelae are present in 55% of the survivors. CONCLUSIONS: Intoxication by methanol and ethylenglycol cause severe metabolic acidosis, with high anion and osmolar gaps which may rapidly lead to death or to sequelae in survivors if diagnosis is delayed and specific treatment is not initiated early.