Department of Pediatrics, Government Medical College and Hospital, Chandigarh, India.
Indian Pediatr. 2013 Apr;50(4):383-9. doi: 10.1007/s13312-013-0119-8. Epub 2012 Oct 5.
(i) To construct hour-specific serum total bilirubin (STB) nomogram in neonates born at =35 weeks of gestation; (ii)To evaluate efficacy of pre-discharge bilirubin measurement in predicting hyperbilirubinemia needing treatment.
Diagnostic test performance in a prospective cohort study.
Teaching hospital in Northern India.
Healthy neonates with gestation =35 weeks or birth weight =2000 g.
Serum total bilirubin was measured in all enrolled neonates at 24 ± 6, 72-96 and 96-144 h of postnatal age and when indicated clinically. Neonates were followed up during hospital stay and after discharge till completion of 7th postnatal day.
Key outcome was significant hyperbilirubinemia (SHB) defined as need of phototherapy based on modified American Academy of Pediatrics (AAP) guidelines. In neonates born at 38 or more weeks of gestation middle line and in neonates born at 37 or less completed weeks of gestation, lower line of phototherapy thresholds were used to initiate phototherapy. For construction of nomogram, STB values were clubbed in six-hour epochs (age ± 3 hours) for postnatal age up to 48 h and twelve-hour epochs (age ± 6 hours) for age beyond 48 h. Predictive ability of the nomogram was assessed by calculating sensitivity, specificity, positive predictive value, negative predictive value and likelihood ratio, by plotting receiver-operating characteristics (ROC) curve and calculating c-statistic.
997 neonates (birth weight: 2627 ± 536 g, gestation: 37.8 ± 1.5 weeks) were enrolled, of which 931 completed followup. Among enrolled neonates 344 (34.5%) were low birth weight. Rate of exclusive breastfeeding during hospital stay was more than 80%. Bilirubin nomogram was constructed using 40th, 75th and 95th percentile values of hour-specific bilirubin. Pre-discharge STB of =95th percentile was assigned to be in high-risk zone, between 75th and 94th centile in upper-intermediate risk zone, between 40th and 74th centile in lower-intermediate risk zone and below 40th percentile in low-risk zone. Among 49 neonates with pre-discharge STB in high risk zone. 34 developed SHB (positive predictive value: 69.4%, sensitivity: 17.1%, positive likelihood ratio: 8.26). Among 342 neonates with pre-discharge STB in low risk zone, 32 developed PHB (negative predictive value: 90.6% and specificity: 42.5%, positive likelihood ratio: 0.37). Area under curve for this risk assessment strategy was 0.73.
Hour-specific bilirubin nomogram and STB measurement can be used for predicting subsequent need of phototherapy. Further studies are needed to validate performance of risk demarcation zones defined in this hour-specific bilirubin nomogram.
（i）构建 35 周胎龄新生儿的小时特异性血清总胆红素（STB）列线图；（ii）评估出院前胆红素测量在预测需要治疗的高胆红素血症中的效果。
前瞻性队列研究中的诊断测试性能。
印度北部的一家教学医院。
胎龄=35 周或出生体重=2000 克的健康新生儿。
所有入组的新生儿在生后 24 ± 6、72-96 和 96-144 小时以及临床需要时测量血清总胆红素。新生儿在住院期间和出院后直至第 7 天接受随访。
关键结局是需要根据美国儿科学会（AAP）修订指南进行光疗的显著高胆红素血症（SHB）。对于 38 周或以上胎龄的新生儿，使用中线；对于 37 周或以下胎龄的新生儿，使用较低的光疗阈值开始光疗。为了构建列线图，将 STB 值按 6 小时间隔（年龄±3 小时）分组，直至出生后 48 小时，按 12 小时间隔（年龄±6 小时）分组，年龄超过 48 小时。通过计算敏感性、特异性、阳性预测值、阴性预测值和似然比、绘制受试者工作特征（ROC）曲线和计算 C 统计量来评估列线图的预测能力。
共纳入 997 名新生儿（出生体重：2627 ± 536 克，胎龄：37.8 ± 1.5 周），其中 931 名完成随访。在入组的新生儿中，344 名（34.5%）为低出生体重儿。住院期间纯母乳喂养率超过 80%。使用特定时间胆红素的第 40、75 和 95 百分位数值构建胆红素列线图。出院前 STB 等于第 95 百分位数被分配到高风险区，第 75 至 94 百分位数分配到上中风险区，第 40 至 74 百分位数分配到中下风险区，第 40 百分位数以下分配到低风险区。在 49 名出院前 STB 处于高风险区的新生儿中，34 名发生 SHB（阳性预测值：69.4%，敏感性：17.1%，阳性似然比：8.26）。在 342 名出院前 STB 处于低风险区的新生儿中，32 名发生 PHB（阴性预测值：90.6%和特异性：42.5%，阳性似然比：0.37）。该风险评估策略的曲线下面积为 0.73。
特定时间的胆红素列线图和 STB 测量可用于预测随后需要光疗的情况。需要进一步的研究来验证该特定时间胆红素列线图中定义的风险划分区的性能。
