Cyanosis, a clinical sign of methemoglobinemia

to present clinical and laboratory characteristics for diagnosing methemoglobinemia. a retrospective revision of last 28 years medical records at the Pediatric National Institute in patients with diagnosis of methemoglobinemia. We review medical drug ingestion, symptoms, oxymetry, gasometry, blood levels of methemoglobin, treatment and evolution. five male patients an one female aged five months to 15 years were studied. Five cases were acquired and one was congenital. Cyanosis was the predominant clinical manifestation. Methemoglobin blood level was between 25 and 50%. The treatment was with intravenous methylene blue with good results in all cases. children with cyanosis who do not have cardiac or pulmonary disease, may have methemoglobinemia. It is necessary to know which drugs develop methemoglobinemia to make the diagnosis of congenital disease in children in order to give the early treatment.