Incidence and mechanism of neonatal jaundice related to glucose-6-phosphate dehydrogenase deficiency.

Abstract

Extract: In three population surveys in Greece, the incidence of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and neonatal jaundice was examined in randomly selected male newborns. The incidence rate of G-6-PD deficiency was 2.92% in the Alexandra survey (population of Athens and southern Greece), 4.93% in the Lesbos survey and 12.5% in the Rhodes survey. In all surveys, severe jaundice without blood group incompatibility or low birth weight appeared much more frequently in G-6-PD-deficient than in normal newborns, but there were striking differences. In Lesbos, severe jaundice was found much more frequently in both G-6-PD-deficient and normal groups than in comparable groups in the other two surveys. Similarly, at 4 days of age, values for serum bilirubin in control groups were 9.43±4.39 mg/100 ml in Lesbos and 7.88±4.8 mg/100 ml in Rhodes (p <0.05). These differences indicate that in Lesbos, an unknown icterogenic factor alone increases the incidence of neonatal hyperbilirubinemia and, in conjunction with G-6-PD deficiency, causes severe neonatal jaundice (serum bilirubin values higher than 16 mg/100 ml) in 43% of G-6-PD deficient infants. In the Rhodes survey, values for hemoglobin and serum bilirubin and reticulocyte count in the G-6-PD-deficient group were compared with values in the cord blood and in samples of blood drawn on the 4th day of life from the control group. The G-6-PD-deficient group had lower hemoglobin values and higher serum bilirubin values than the control group. The mean values (g/100 ml) for hemoglobin in cord blood were 14.42±1.24 and 15.36±1.36 in the G-6-PD-deficient and control groups, respectively. In samples obtained at 4 days of age, the values were 15.6±1.34 and 16.65±1.37, respectively, in the two groups. The mean values (mg/100 ml) for serum bilirubin in cord blood were 1.98±0.64 and 1.68±0.42, respectively, in the two groups. At 4 days of age, the values were 9.86±6.6 and 7.88±4.8, respectively. These results indicate a diminished life span of G-6-PD-deficient erythrocytes in the fetal and neonatal period. Speculation: This study demonstrates the existence in some newborn populations of an icterogenic factor unrelated to blood group incompatibility or G-6-PD deficiency. Further studies are needed to determine the hemolytic or hepatic nature of this factor and whether this factor interacts with ABO incompatibility or prematurity. In this work, the relation of this factor to G-6-PD deficiency has been studied.