Severe methemoglobinemia due to insecticide poisoning

Abstract

Methemoglobinemia is an altered state of hemoglobin resulting in impaired oxygen delivery to the tissues. Deliberate ingestion of certain insecticides and pesticides may result in this condition. We report a case of severe methemoglobinemia after deliberate ingestion of an insecticide marketed to be safe and containing only biological extracts and fillers. Methemoglobinemia should be suspected with low oxygen saturation on pulse oxymetry and the presence of chocolate colored blood. The methemoglobin level of 91% in our patient is the highest level reported among methemoglobinemia survivors.

Methemoglobinemia Due to Biological Poisoning – Case Report

“…Severe methemoglobinemia (MetHb>70%) is usually fatal, as evidenced in our first case though survival has been reported with a MetHb level of 80% in our case2 and previous reports (4,10).…”

“…The clinical manifestations (Table I) of methemoglobinemia are due to impaired oxygen delivery to the tissues and hence correlate with severity of methemoglobinemia. The onset of signs and symptoms in our cases was 30-60 minutes after pesticide ingestion.We observed bilateral pin point pupils in two cases and positive troponin and myoglobin in one case but this finding was not seen with similar poisoning described by George et al (4).…”

A Rare Cause of Methemoglobinemia: How Safe are So-called Biopesticide?

“…However, search has shown that biological extracts are known to be rich in nitrogenous products and may potentially cause methemoglobinemia. 6 In our patient, diagnosis of methemoglobinemia was made on triad of saturation gap, cyanosis, and dark blood. Early recognition and on symptomatic treatment led to recovery with normal neurological function.…”

Management of Herbicide Induced Methemoglobinemia

“…Acquired Methemoglobinemia occurs as a result of many drugs with oxidizing effects and when methemoglobins are more than the reductive capacity of the Generally 10%-20% of methemoglobin levels are well tolerated and the symptoms are usually detected when the levels are more than 20%. Methemoglobinemia levels higher than 70% may lead to coma and death [4,5].…”