Methemoglobinemia secondary to cleaning solution ingestion

Methemoglobinemia is a rare cause of cyanosis in pediatric patients. A 16-month-old male presented to the Emergency Department cyanotic and short of breath after ingestion of a hair-care-equipment cleaning solution. After calling the salon and consulting Poisindex, the substance was found to be Mar-V-cide, containing 20% Hyamine 3500, 50% cationic detergents, 20% isopropyl alcohol, and 1% sodium nitrite, which caused the methemoglobinemia in this case. Initial pulse oximetry on room air was 72% and improved minimally with supplemented oxygen. The patient's methemoglobin level was 63%. Methylene blue was administered (2 mg/kg intravenously), and the patient rapidly improved. Nitrates occur in high concentrations in some food and water. Infants are particularly susceptible to chronic nitrate-induced methemoglobinemia because of their low stomach acid production, large numbers of nitrite-reducing bacteria, and the relatively easy oxidation of fetal hemoglobin. Acute nitrite toxicity results from industrial exposure, accidental ingestion (e.g., abuse of organic nitrites as an aphrodisiac, especially in the male homosexual population), and suicidal ingestion. Methemoglobinemia may occur in a number of drug or chemical ingestions, but a comprehensive review of the literature failed to identify a similar reported case.