Severe-glucose-6-phosphate dehydrogenase (G6PD) deficiency associated with chronic hemolytic anemia, granulocyte dysfunction, and increased susceptibility to infections: description of a new molecular variant (G6PD Barcelona).
Molecular , kinetic , and functional studies were carried out on erythrocytes and leukocytes in a Spanish male with G6PD deficiency , congenital nonspherocytic hemolytic anemia ( CNSHA ) , and increased susceptibility to infections . G6PD activity was absent in patients red cells and was about 2 % of normal in leukocytes . Molecular studies using standard methods ( WHO , 1967 ) showed G6PD in the patient to have a slightly fast electrophoretic mobility at pH 8 . 0 with otherwise normal properties ( heat stability at 46 degrees C , apparent affinity for substrates , optimum pH , and utilization of substrate analogues ) . Other tests showed the patients granulocytes to engulf latex particles normally , but to have impaired reduction of nitroblue tetrazolium and ferricytochrome-c as well as reduced iodination . Chemotaxis and random migration of the patients granulocytes were normal as were myeloperoxidase , leukocyte alkaline phosphatase ( LAP ) , and ultrastructural features . The molecular characteristics of G6PD in the patient differed from those of all previously reported variants associated with CNSHA , so the present variant was provisionally called G6PD Barcelona to distinguish it from other G6PD variants previously described . Possible mechanisms for the severe deficiency of G6PD in erythrocytes and granulocytes was investigated by studies on the immunologic specific activity of the mutant enzyme .
