Methemoglobinemia caused by fungicide poisoning: A case report

Methemoglobinemia is a potentially fatal condition at level of more than 70%. It occurs when the ferrous iron inHaemoglobin oxidized to ferric iron, forming methemoglobin (MetHb), causing decreased capability hemoglobinto bind and deliver oxygen tissues. has been linked wide array substances, includingfungicides industrial chemicals. We describe patient who developed high MetHb 70.7%, afterdeliberately consuming fungicide, namely Mancozeb. The "oxygen saturation gap" difference between thecalculated from standard blood gas machine reading pulse oximeter. If it greaterthan 5%, patient's hemoglobin may be abnormal, representing carbon monoxide poisoning, methemoglobinemia,or sulfhemoglobinemia. Disproportionate cyanosis not responding supplemental oxygen, chocolate brown blood,and gap >5% raised suspicion methemoglobinemia secondary ingestion fungicide. Analternative approach treatment including intravenous ascorbic acid, NAC, multiple transfusions wasgiven due unavailability methylene blue. A index suspicion, early recognition, an alternativeapproach management resulted in favorable outcome.
 Bangladesh Crit Care J March 2023; 11 (1): 46-50