Objective: To investigate the correlation between hypoglycemia and positive rate of inborn error of metabolism (IEM) in neonatal intensive care unit.
Methods: 160 patients from a neonatal intensive care unit were enrolled. Blood glucose was measured by Roche Modular chemistry. The dry blood on filter papers, collected from 160 patients, was tested by tandem mass spectrometry to detect 35 inborn errors of metabolism. Clinical follow-up of all the patients was at least in an interval of 12 months. The mean observation period was 13.5 months per child.
Findings: Based on the ROC curve, the optimal cut-off value of hypoglycemia as an indicator for screening for IEMs was projected to be 2.8 mmol/L, which yielded a sensitivity of 71.4% and a specificity of 76.5%. The patients were divided into two groups: hypoglycemia group (48 cases) and the control group (112 cases). 5(10.4%) of the 48 patients in the hypoglycemia group were positive, while only 2(1.8%) of the 112 patients in the control group were positive. The difference of the positive rate in the screening for IEMs between the two groups was significant (χ(2)=4.10, P<0.05); the relative risk (RR) was 5.83 (95% CI: 1.06-32.12).
Conclusion: The risk of patients with hypoglycemia suffering from IEMs was significantly higher than that of the non-hypoglycemia patients in NICU, based on cut-off value of 2.8mmol/L.
Keywords: Hypoglycemia; Inborn Errors of Metabolism; Neonatal Intensive Care Units; Tandem Mass Spectrometry.