Hereditary diaphorase deficiency methemoglobinemia in Maltese families

Abstract

Methemoglobin (ferrihamoglobin) normally constitutes only 1% of the total hemoglobin of the red cells. Its presence in a greater concentration is pathological and may be due to a number of different causes, congenital or acquired. Hereditary Diaphorase Deficiency Methemoglobinemia was discovered in seven persons belonging to four Maltese families. These are the first families of diaphorase deficiency methemoglobinemia to be recorded from the Maltese Islands. The case reports of the seven affected individuals are hereby described and discussed with particular reference to other medical literature and studies. It is suggested that the gene frequency for this type of congenital methemoglobinemia is high in the Maltese Islands and that wider systematic surveys would reveal many more cases.