G-6 PD Screening in Neonatal Hyperbilirubinemia

Glucose-6-Phosphate Dehydrogenase deficiency (G6PDD), is one of the commonest X-linked inherited erythroenzymopathy affecting 10% of the world population with a frequency of 0-27% in India. Children with G6PDD can develop acute hemolytic crises precipitated by particular foods or drugs causing significant morbidity. As primary prevention is not available, the only way to avoid morbidity is to recognize such children early in life and prevent exposure to triggering agents and drugs. Aims/ Objectives: 1. To screen and determine the frequency of G6PDD in cases of neonatal hyperbilirubinemia ( > 12.9 mg/dl). 2. To assess the usefulness of methemoglobin reduction (MR) test in neonatal screening for G6PDD. Results: This observational study conducted in the department of pathology, at Kempegowda Institute of Medical Sciences, Bengaluru included 310 neonates with hyperbilirubinemia (12.9gm%). The male: female ratio was 1.3:1 with 80.3% of neonates presenting between 3-5 days post-birth with jaundice. Majority of the neonates were from non-consanguineous marriages (91.65%). Birth weight of 83.7% of the neonates was found to be > 2.5 kgs. Frequency of G6PDD was 1% ( 3 females) by MR test. All the G6PD deficient neonates (3/310 cases) were females (P=0.045), from non-consanguineous marriages. Conclusion: Frequency of G6PDD in neonatal hyperbilirubinemia was 1% (3/310 cases) suggesting low prevalence in south India. MR test appeared to be a good screening test as it was effective in picking up heterozygotes (all three were females, P=0.045). G-6PD Screening in Neonatal Hyperbilirubinemia Suvitha Thilakarajan et al., G-6PD Deficiency Screening in Neonatal Hyperbilirubinemia www.ijnmr. net Indian Journal of Neonatal Medicine and Research. 2014 Nov, Vol-3(3): 1-6 2 [Table/Fig-1]: MRT of Case No. 122, showing a negative reaction PC – Positive Control, NC – Negative Control, T – Test [Table/Fig-4]: Distribution of various blood groups in study population [Table/Fig-2]: MRT of Case No. 28 showing an intermediate reaction PC – Positive Control, NC – Negative Control, T – Test Karnataka. This study population consisted of 310 neonates (birth to 28 days) who had hyperbilirubinemia and were admitted in the NICU. The inclusion criteria were all term (>36 weeks gestational age) neonates with hyperbilirubinemia (total serum bilirubin > 12.9 mg/dl). Neonates with total serum bilirubin < 12.9 mg/dl and premature neonates (less than 36 weeks of gestation) with hyperbilirubinemia were excluded from the study. The relevant personal history was obtained from the hospital records as per the proforma. MATERIALS 0.5 ml of venous blood was collected into a tube containing EDTA (1mg/1ml). All cases were screened for G6PD deficiency by Methemoglobin Reduction Method METHEMOGLOBIN REDUCTION TEST Principle: In this reaction, Sodium Nitrite converts haemoglobin to methemoglobin . When no methylene blue is added methemoglobin persists but, incubation of samples with Methylene Blue allows the stimulation of the pentose phosphate pathway in subjects with normal G6PD levels. The methemoglobin is then reduced during the incubation period to haemoglobin. In G6PD deficient subjects, the block in the pentose phosphate pathway prevented this reduction and the methemoglobin remained