Jaundice Due to Glucose-6-Phosphate Dehydrogenase Deficiency

Abstract

Glucose-6-phosphate dehydrogenase (G6PD) deficiency complicates the usually benign neonatal jaundice managed by existing prenatal and postnatal screening in the United States. Estimated at ∼3.4% incidence, the condition ranges by infant race/ethnicity (12.2% in African American male infants to nearly 0% in white female infants). Oxidant stressors, sepsis, and delay in bilirubin elimination (such as co-inheritance with Gilbert's disease or persistent enterohepatic recirculation) add to total plasma or serum bilirubin (TSB) rise, need for phototherapy, and risk for exchange transfusion. Biology of G6PD deficiency, in the context of gender, race, ethnicity, enzyme concentration, and interaction with postnatal environment, affects clinical presentations. Mutation of the X-linked G6PD gene results in varying enzyme activity. A combination of clinical patterns are suggested: (1) early-onset hyperbilirubinemia (ie, TSB >75th percentile and increased bilirubin production); (2) predischarge TSB <75th percentile track exacerbated by starvation, unrecognized sepsis or late prematurity; (3) slow postnatal rise with natural decline; (4) slow postnatal rise with persistent prolonged unconjugated hyperbilirubinemia, >2 weeks age; and (5) complicated by acute-onset, dramatic hyperbilirubinemia with TSB rise >1 mg/dL per hour (“favism”). Absent G6PD deficiency diagnosis, postdischarge management for phototherapy requires expert assessment and triage for probable risk of favism. Screening as well as clinician and parental awareness of G6PD enzyme deficiency has been shown to reduce adverse neonatal consequences in several communities worldwide.