极低出生体质量儿中性粒细胞参考范围的建立及其在诊断败血症中的应用

摘要

Objective To establish the reference ranges for neutrophils in very low birth weight (VLBW) infants in the southwest area of China and to evaluate their application in the diagnosis of septicemia .Methods The clinical data from the VLBW infants without relative complications were collected retrospectively .The reference ranges for absolute total neutrophil count (ATN) , absolute total immature neutrophil count (ATI) and the ratio of immature neutrophils to total neutrophils (I/T ratio) were established by calculating the mean ,5th and 95th percentile intervals ,and the sensitivity ,specificity ,positive predictive value and negative predictive value of neutrophilic indices used in diagnosing VLBW septicemia were compared .Results The peak of ATN occurred at about 10 h after birth ,and remained stable after 60 h with a maximum of 8 .52×109 /L, and a minimum of 1 .94×109/L .The peak of ATI occurred at 10-12 hand reached the stable value of 0.50×109/L after 120 h .The upper limit of I/T ratio was 0.16 at birth and then declined to 0 .13 beyond 60 h .In diagnosing septicemia with single index ,ATN showed the highest sensitivity 64 .10% and the highest negative predictive value 92 .76%. I/T ratio showed the highest specificity of 91 .50% and the highest positive predictive value of 40 .91% .Parallel combined test showed 74 .36% sensitivity and 93 .08% negative predictive value .Conclusion The newly established domestic reference ranges for neutrophils in VLBW infants have the important value in diagnosing septicemia in VLBW infants.%目的 建立极低出生体质量儿(VLBW)外周血中性粒细胞各参数的参考范围,并评价其在诊断败血症中的实用性.方法 回顾性收集无相关并发症的VLBW的临床资料,通过计算中性粒细胞绝对计数(ATN)、未成熟中性粒细胞绝对计数(ATI)及未成熟中性粒细胞与总中性粒细胞比值(I/T)各时间段的均值、第5百分位和第95百分位,建立各参数的参考范围,并比较各参数在诊断VLBW败血症时的灵敏度、特异度、阳性预测值及阴性预测值.结果 ATN在生后约10 h出现峰值,60 h左右达到基本稳定,上限为8.52×109 /L,下限为1.94×109 /L.ATI在生后10～12 h达到高峰,120 h后维持在0.50×109 /L.I/T值上限在出生时为0.16,生后60 h左右降至0.13,后逐渐趋于稳定.在诊断VLBW败血症时,单项参数中ATN有最高的的灵敏度和阴性预测值,分别为64.10%和92.76%.I/T有最高的特异度和阳性预测值,分别为91.50%和40.91%.平行联合诊断检验时,灵敏度和阴性预测值最高,分别为74.36%和93.08%.结论 建立国内的VLBW中性粒细胞参考范围,对临床诊断VLBW败血症有重要的价值.