Screening of pyruvate kinase deficiency and G6PD deficiency in Chinese newborn in Hong Kong.

In recent reports, pyruvate kinase deficiency (PK deficiency) and glucose-6-phosphate dehydrogenase (G6PD) deficiency appear to be the most common deficiencies associated with the syndrome of congenital non-spherocytic haemolytic anaemia.Many of these cases have been reported to be associated with neonatal jaundice of varying degrees of severity.This study was undertaken to find the incidence of PK deficiency and G6PD deficiency in the Chinese newborn in Hong Kong, and the possible relation of PK deficiency with neo- natal jaundice.The relation of G6PD deficiency and neonatal jaundice had been well established in many studies throughout the world including Chinese neonates in Hong Kong. Material and MethodsFrom March 1, 1968, to May 5, 1968, 700 consecutive newborn babies born at Tsan Yuk Hospital were screened for PK and G6PD deficiencies.The methods used were described by Beutler (1966).In these procedures, advantage is taken of the fact that even minute quantities of reduced pyridine nucleotides fluoresce intensely when activated with long-wave ultraviolet light.These tests are based upon the reduction of oxidized pyridine nucleotide in the case of G6PD deficiency, or on the oxidation of a reduced pyridine nucleotide in the case of PK deficiency.In G6PD deficiency, there is absence of fluorescence under long-wave ultraviolet light, whereas the fluores- cence persists after incubation in PK deficiency.In Beutler's original description of his method, detection of the heterozygote in G6PD deficiency presents more of a problem than in PK deficiency because of the rapidity of the reaction time in the former.In this study, we made no attempt to separate the heterozygote from the homozygote in G6PD deficient individuals.However, in PK deficiency Beutler showed that homozy- gous individuals uniformly showed persistence of the fluorescence 1 hour or more after incubation at 37 'C.while heterozygote individuals showed disappearance of the fluorescence before 1 hour but later than normal individuals, i.e. after 15 minutes of incubation.In