Lower reference limits of quantitative cord glucose-6-phosphate dehydrogenase estimated from healthy term neonates according to the clinical and laboratory standards institute guidelines: a cross sectional retrospective study

Abstract

BackgroundPrevious studies have reported the lower reference limit (LRL) of quantitative cord glucose-6-phosphate dehydrogenase (G6PD), but they have not used approved international statistical methodology. Using common standards is expecting to yield more true findings. Therefore, we aimed to estimate LRL of quantitative G6PD detection in healthy term neonates by using statistical analyses endorsed by the International Federation of Clinical Chemistry (IFCC) and the Clinical and Laboratory Standards Institute (CLSI) for reference interval estimation.MethodsThis cross sectional retrospective study was performed at King Abdulaziz Hospital, Saudi Arabia, between March 2010 and June 2012. The study monitored consecutive neonates born to mothers from one Arab Muslim tribe that was assumed to have a low prevalence of G6PD-deficiency. Neonates that satisfied the following criteria were included: full-term birth (37 weeks); no admission to the special care nursery; no phototherapy treatment; negative direct antiglobulin test; and fathers of female neonates were from the same mothers’ tribe. The G6PD activity (Units/gram Hemoglobin) was measured spectrophotometrically by an automated kit. This study used statistical analyses endorsed by IFCC and CLSI for reference interval estimation. The 2.5th percentiles and the corresponding 95% confidence intervals (CI) were estimated as LRLs, both in presence and absence of outliers.Results207 males and 188 females term neonates who had cord blood quantitative G6PD testing met the inclusion criteria. Method of Horn detected 20 G6PD values as outliers (8 males and 12 females). Distributions of quantitative cord G6PD values exhibited a normal distribution in absence of the outliers only. The Harris-Boyd method and proportion criteria revealed that combined gender LRLs were reliable. The combined bootstrap LRL in presence of the outliers was 10.0 (95% CI: 7.5-10.7) and the combined parametric LRL in absence of the outliers was 11.0 (95% CI: 10.5-11.3).ConclusionThese results contribute to the LRL of quantitative cord G6PD detection in full-term neonates. They are transferable to another laboratory when pre-analytical factors and testing methods are comparable and the IFCC-CLSI requirements of transference are satisfied. We are suggesting using estimated LRL in absence of the outliers as mislabeling G6PD-deficient neonates as normal is intolerable whereas mislabeling G6PD-normal neonates as deficient is tolerable.

Multisystem Inflammatory Syndrome in Children, the Real Disease of COVID-19 in Pediatrics - A Multicenter Case Series From Al-Ahsa, Saudi Arabia

“…One of the interesting observations in our findings that three patients (30%) had underlying G6PD deficiency, which is very prevalent in Al-Ahsa, Saudi Arabia (23% prevalence rate) [ 7 ]. Wu et al wrote that G6PD-deficient cells are more vulnerable to human coronavirus infection than G6PD-normal cells [ 8 ] but we do not know if G6PD deficiency is a risk factor for severe COVID-19 disease or severe MIS-C.…”

Prolonged indirect hyperbilirubinemia in a moderately preterm boy with Mediterranean glucose-6-phosphate dehydrogenase and glutathioneS-transferase Mu 1 null mutations

“…Identifying G6PD Mediterranean in the proband case and one of his brothers is expected for two reasons. First, their cord G6PD levels were extremely low 9. Second, the G6PD Mediterranean is the most common type of G6PD deficiency among people from AL-Ahsa area, Eastern Province of Saudi Arabia 10…”

Decreased Glutathione S-transferase Level and Neonatal Hyperbilirubinemia Associated with Glucose-6-phosphate Dehydrogenase Deficiency: A Perspective Review

“…Gestational age is an important confounder in such studies as cord blood GST and G6PD levels inversely correlate with gestational age. 60,61 Perinatal asphyxia and resuscitation with 100% oxygen can also affect cord GST levels, a factor that was not examined in the above study. In addition, cord GST levels have been found to be higher in sick preterm neonates compared with healthy preterm neonates.…”