Objective: To evaluate relations between production and conjugation of biliru bin in the pathophysiology of jaundice in glucose- 6- phosophate dehydrogenase (G6PD) deficient neonates. Methods: Term and borderline prem...Objective: To evaluate relations between production and conjugation of biliru bin in the pathophysiology of jaundice in glucose- 6- phosophate dehydrogenase (G6PD) deficient neonates. Methods: Term and borderline premature (35- 37 week s gestational age), healthy, male, G6PD deficient neonates were studied close to the beginning of the 3rd day. Blood carboxyhaemogobin corrected for inspired CO (COHbc; an index of bilirubin production) and serum total conjugated bilirubin (TCB; a reflection of bilirubin conjugation) were measured in simultaneously dra wn blood samples by gas chromatography and reverse phase high performance liquid chromatography respectively. A bilirubin production- conjugation index compris ing COHbc/TCB was determined; a high index reflects imbalance between the biliru bin production and conjugation processes. COHbc and TCB individually and the pro duction- conjugation index were studied in relation to serum total bilirubin (S TB)- concentration. Results: Fifty one G6PD deficient neonates were sampled at 51 (8) hours. COHbc values did not correlate with STB (r = 0.22, p = 0.15). TCB did correlate inversely with STB (r = - 0.42, p = 0.004), and there was a posit ive correlation between the production- conjugation index and STB (r = 0.45, p = 0.002). The production- conjugation index (median (interquartile range))was h igher in the premature (n = 8) than term neonates (2.31 (2.12- 3.08) v 1.05 (0. 53- 1.81), p = 0.003). This difference was the result of changes in TCB. Conclu sions: The data show that jaundice in G6PD deficient neonates is the result of a n imbalance between production and conjugation of bilirubin with a tendency for inefficient bilirubin conjugation over increased haemolysis in its pathogenesis. Borderline premature infants are at especial risk of bilirubin production- con jugation imbalance.展开更多
文摘Objective: To evaluate relations between production and conjugation of biliru bin in the pathophysiology of jaundice in glucose- 6- phosophate dehydrogenase (G6PD) deficient neonates. Methods: Term and borderline premature (35- 37 week s gestational age), healthy, male, G6PD deficient neonates were studied close to the beginning of the 3rd day. Blood carboxyhaemogobin corrected for inspired CO (COHbc; an index of bilirubin production) and serum total conjugated bilirubin (TCB; a reflection of bilirubin conjugation) were measured in simultaneously dra wn blood samples by gas chromatography and reverse phase high performance liquid chromatography respectively. A bilirubin production- conjugation index compris ing COHbc/TCB was determined; a high index reflects imbalance between the biliru bin production and conjugation processes. COHbc and TCB individually and the pro duction- conjugation index were studied in relation to serum total bilirubin (S TB)- concentration. Results: Fifty one G6PD deficient neonates were sampled at 51 (8) hours. COHbc values did not correlate with STB (r = 0.22, p = 0.15). TCB did correlate inversely with STB (r = - 0.42, p = 0.004), and there was a posit ive correlation between the production- conjugation index and STB (r = 0.45, p = 0.002). The production- conjugation index (median (interquartile range))was h igher in the premature (n = 8) than term neonates (2.31 (2.12- 3.08) v 1.05 (0. 53- 1.81), p = 0.003). This difference was the result of changes in TCB. Conclu sions: The data show that jaundice in G6PD deficient neonates is the result of a n imbalance between production and conjugation of bilirubin with a tendency for inefficient bilirubin conjugation over increased haemolysis in its pathogenesis. Borderline premature infants are at especial risk of bilirubin production- con jugation imbalance.