Cyanosis Due to Methemoglobinemia as the Presenting Sign of Glucose-6-Phosphate Dehydrogenase Deficiency in a Child: Diagnostic and Clinical Implications.

A previously healthy 3-year-old boy presented with pallor, jaundice, cyanosis, and a 24-hour history of vomiting and anorexia following fava bean ingestion. Clinical examination and laboratory findings were consistent with severe nonimmune hemolytic anemia with methemoglobinemia. Given the patient's history, a previously unrecognized glucose-6-phosphate dehydrogenase deficiency was suspected and diagnosed. The aim of this article is to delineate the possible coexistence of methemoglobinemia and glucose-6-phosphate dehydrogenase deficiency in children presented with acute hemolysis and discuss its management while reviewing the existing literature.