早产儿早发败血症与胸腺大小及功能之间的关系

Relationship Between Early-onset Sepsis and the Size and Function of Thymus Among Preterm Neonates

目的研究早发败血症对早产儿胸腺大小及免疫功能的影响。方法采用前瞻性病例对照研究方法,收集2019.1~2019.12华中科技大学同济医学院附属协和医院新生儿重症监护病房胎龄<32周的早产儿病例,包括围产期资料和一般资料,并收集患儿出生后24 h内淋巴细胞的计数资料。败血症组为确诊早发败血症早产儿,对照组患儿为非败血症早产儿。纳入研究的早产儿出生24 h内行床边胸腺B超检查,测量其最大横径和长轴截面积,计算胸腺指数(TI)和胸腺/体重指数(TWI)。并分析胸腺大小和淋巴细胞数目的相关性。结果共收集早产儿病例72例,早发败血症组24例,按胎龄和体重匹配的对照组48例。与对照组相比,败血症组患儿绒毛膜羊膜炎发生率显著增高(29.2%vs.8.3%,P<0.05),胎膜早破和产前激素使用率无明显差异。败血症组TI[(1.496±0.439)cm^(3)]和TWI[(1.164±0.232)cm^(3)/kg]较对照组[TI:(2.304±0.790)cm^(3),TWI:(1.748±0.438)cm^(3)/kg]均明显减小(均P<0.05),淋巴细胞计数较对照组明显降低[(3.34±1.54)×10^(9)/L vs.(4.29±1.85)×10^(9)/L,P<0.05],并且淋巴细胞数目和TI呈正相关(r=0.238,P<0.05)。结论早发败血症早产儿胸腺发生萎缩,影响早产儿免疫功能。

Objective To study influence of early-onset sepsis(EOS)on the size and function of thymus among preterm neonates.Methods This prospective study examined perinatal data from preterm neonates born at<32 weeks of gestation in a neonatal intensive care unit between January 2019 and December 2019.EOS was defined as a culture-confirmed infection that occurred within 72 h after birth.The largest transverse diameter and the sagittal of thymus were measured by ultrasonography within 24 h of birth in the EOS neonates and the controls.And thymic index(TI)and thymic weight index(TWI)were calculated to assess the thymus volume.Data were analyzed by SPSS 17.0.Results Seventy-two preterm neonates were enrolled in our study.Twenty-four preterm neonates with EOS comprised the study group,and 48 gestational age-and gender-matched neonates without EOS served as controls.Compared with the control group,the incidence of chorioamnionitis was significantly higher in the EOS group(29.2%vs.8.3%,P<0.05).EOS group showed significantly smaller TI and TWI than control group[TI:(1.496±0.439)cm^(3)vs.(2.304±0.790)cm^(3),TWI:(1.164±0.232)cm^(3)/kg vs.(1.748±0.438)cm^(3)/kg],as well as lower lymphocyte count[(3.34±1.54)×10^(9)/L vs.(4.29±1.85)×10^(9)/L]in preterm neonates with EOS(all P<0.05).Significant correlation was noted between TI and the absolute lymphocyte counts(r=0.238,P<0.05).Conclusion Thymic involution was associated with EOS in preterm neonates,and affected their immune function.