A Unique Case of Methanol Toxicity

Abstract

SESSION TYPE: DVT/PE/Pulmonary Hypertension Posters IPRESENTED ON: Wednesday, October 24, 2012 at 01:30 PM - 02:30 PMINTRODUCTION: In patients presenting with volatile alcohol toxicity early diagnosis and treatment is critical to prevent organ damage and death. The goal standard for diagnosing methanol and ethylene glycol (EG) toxicity is gas chromatography. Results can take up to days and many hospitals are not equipped to provide such test. Clinicians must rely on the clinical presentation and other laboratory tests such osmolar gap (OG) to make a diagnosis. An OG of >10 indicates the presence of other osmoles in the blood such as methanol or EG. We present a case with severe methanol toxicity and a normal OG.CASE PRESENTATION: A 48 year old Caucasian male was admitted to a community hospital where he presented 20 minutes after ingesting over 500 tablets of extra-strength Tylenol. Upon presentation, N-acetylcysteine infusion was initiated. Subsequently patient required intubation and mechanical ventilation due to impending respiratory failure. Initial laboratory work up revealed an Acetaminophen level of 86 mg/L, normal OG, high anion gap metabolic acidosis, negative urine analysis and serum drug screen. He was then transferred to our hospital for further management. Upon arrival to our hospital (tertiary center), the patient had multisystem organ failure. Acetaminophen level was >800 mg/L, therefore activated charcoal was administered. On Hospital day 2 metabolic acidosis persisted, therefore, volatile gas screen was ordered. Results reported in 3 hours were positive for methanol. The patient was started on renal replacement therapy and Fomepizole.The remaining of the hospital course was significant for development of cerebral edema for which hypothermia protocol was initiated. Also, the patient developed an upper gastrointestinal bleed, which was consistent with caustic ingestion. After 2 weeks in the intensive care unit, the patient eventually made a miraculous recovery and returned to baseline mental status and function.DISCUSSION: Perhaps a OG of < 10 should be considered elevated as there may be patients with a normal osmolar gap of -2 +/- 6 (as in children). Also, once methanol is converted to its toxic metabolite, formic acid, this compound is no longer osmotically active and thus the OG will return to normal.CONCLUSIONS: Methanol toxicity can be managed effectively if diagnosed early during the clinical course. Although an elevated OG is highly sensitive for volatile alcohol intoxication, a normal OG does not necessarily rule-it out (not specific). Therefore, treatment should be started immediately if volatile gas toxicity is suspected by the treating clinician.1) Jammalamadaka, Divakar MD, et al. Ethylene Glycol, Methanol and Isopropyl Alcohol Intoxication. American Journal of the Medical Sciences. 339(3):276-281, March 2010.DISCLOSURE: The following authors have nothing to disclose: Maria Herrera, Christiane MbiandaNo Product/Research Disclosure InformationMedical College of Wisconsin, Milwaukee, WI