[Familial case of methemoglobinemia associated with glucose-4-phosphate dehydrogenase deficiency].

More than 1500 umbilical blood samples from newborns were examined by modified analytical isoelectric focussing method on polyacrylamide-ampholine gels at Ph3.5-9.5 and 5.5-8.5 with Multiphor-2117. Hemoglobin fractions were measured by laser densitometer 22P2 (LKB, Sweden). Methemoglobinemia type was identified by methemoglobin content, methemoglobin reductase activity, Betke's coefficient, and by analyzing the spectra of blood hemolysates containing group M hemoglobin. Methemoglobinemia due to low methemoglobin reductase activity was detected in one child. Increased levels of methemoglobin were detected in his father, mother, grandmother, and grandfather. Methemoglobin reductase activity was not detected in the proband, his mother and grandfather. Zero methemoglobin reductase activity in the proband was combined with zero glucose-6-phosphate dehydrogenase activity. Grandmother was found to be a heterozygotic carrier of these enzymes genes. Glutathione reductase activity was found reduced below the norm in all the members of this family.