微粒体基因16SrRNA在宫内感染诊断中的意义探讨

Value of microbial gene 16SrRNA in the identification of antenatal infection

摘要:

目的：探讨微粒体基因与宫内感染的关系。方法：单胎早产出生者30例为病例组，按照早产原因分为胎膜早破（PROM）组16例（早破膜时间均＞18 h），自发性早产(SPL)组6例，有指征的医源性早产（包括母亲或胎儿原因）8例，另选取10例单胎足月出生者作为对照组。分别留取部分胎盘、胎膜、羊水、脐血、气管分泌物、胃液及新生儿静脉血等，观察各种原因早产胎盘、胎膜病理改变；用PCR方法分别测定微粒体基因16SrRNA及解脲脲原体(UU)基因在胎盘及胎膜等各类标本中的表达。结果：病例组中21例（70%）诊断为绒毛膜羊膜炎，主要病理改变为胎膜、胎盘组织中性粒细胞浸润，胎膜改变尤为明显，主要见于胎龄＜32周或出生体重＜1 500 g者。病例组30例患儿中，16SrRNA基因阳性12例，UU基因阳性10例，对照组10例患儿均未检测到16SrRNA及UU基因。PROM组早产儿生后感染发生率高于其他原因早产患儿，但差异无统计学意义。结论：绒毛膜羊膜炎是导致胎膜早破及胎儿早产的主要原因，检测微粒体基因可间接反映是否有宫内感染存在。［中国当代儿科杂志，2010，12（9）：726-729］

Abstract:

OBJECTIVE: To study the relationship between microbial gene 16SrRNA and intrauterine infection. METHODS: Thirty cases of single preterm birth were enrolled, including 16 cases due to premature rupture of membranes (PROM) (rupture time>18 hrs), 6 cases due to spontaneous preterm birth and 8 cases due to iatrogenic preterm birth. Ten cases of single term birth were used as the control group. Fetal membrane and placenta samples were obtained. Amniotic fluid, blood from cord or newborn babies as well as gastric fluid and tracheal secretions from infants with mechanical ventilation were also obtained. The histological features of placenta and fetal membranes were observed. Polymerase chain reaction (PCR) was used to detect the presence of microbial 16SrRNA and ureaplasma urealyticum (UU) in placenta, fetal membranes and other samples. RESULTS: Twenty-one (70%) cases were diagnosed as chorioamnionitis, characterized by neutrophil infiltration in fetal membrane and placenta tissues, especially in fetal membranes. Chorioamnionitis was most frequent in babies whose gestational age less than 32 weeks or birth weight lower than 1 500 g. Positive 16SrRNA gene was found in 12 cases, and positive UU gene in 10 cases in the preterm birth group. Neither 16SrRNA nor UU gene was detected in the control group. The PROM preterm babies developed more frequent infection than the babies premature born due to other causes, but there were no statistically significant differences in the incidence of infection. CONCLUSIONS: Chorioamnionitis may be the major cause of PROM and premature birth. The detection of microbial genes is valuable in identification of intrauterine infection.［Chin J Contemp Pediatr, 2010, 12 (9):726-729］