McDuffie R S, Blanton S J, Charland S L, Gibbs R S
Department of Obstetrics and Gynecology, Kaiser Permanente, Denver, Colorado, USA.
Am J Obstet Gynecol. 1996 Aug;175(2):406-10. doi: 10.1016/s0002-9378(96)70154-0.
Our purpose was to evaluate the effect of maternal administration of ampicillin-sulbactam on group B streptococcal colonization and bacteremia in newborn rabbits.
Before induction of labor, timed pregnant New Zealand White rabbits on day 29 of a 31-day gestation received no therapy or ampicillin-sulbactam 50 mg/kg intramuscularly as a single dose 2 to 8 hours before delivery. Labor was induced with oxytocin. After delivery, the oropharynx of each pup was inoculated with 10(9) cfu of type la group B Streptococcus. Cultures of each pup were taken from the oropharynx and anorectum daily and from the heart at death or after 96 hours. Ampicillin-sulbactam concentrations were determined at delivery in both mothers and pups.
Thirteen animals were assigned to no therapy and 14 animals to ampicillin-sulbactam. Untreated pups had 100% oropharyngeal colonization at 24 hours. Pups treated with antibiotic were significantly less likely to have positive oropharyngeal cultures at 24 and 48 hours after birth than did untreated pups (24 hours 47% vs 100%, p < 0.0001; 48 hours 68% vs 91%, p = 0.0006). For anorectal cultures treated pups were significantly less likely to have positive culture results. Heart cultures were also less likely to have positive results for treated animals at 48 and 72 hours than for untreated animals (48 hours 30% vs 96%, p = 0.0001; 72 hours 31% vs 71%, p = 0.03). Treated pups had higher rates of survival at 48 hours (89% vs 62%, p < 0.0001). When neonatal oropharyngeal colonization at 24 hours after birth was compared with length of time from maternal antibiotic injection to delivery, there was a significant polynomial relationship (r = 0.78, p < 0.05). Ampicillin-sulbactam serum concentrations were highest 3 to 5 hours after injection. An inverse relationship existed between the rate of neonatal oropharyngeal colonization with group B streptococci at 24 hours after birth and neonatal ampicillin serum concentrations near birth (r = 0.733).
Transplacental treatment with a single intramuscular dose of ampicillin-sulbactam significantly decreased neonatal colonization and bacteremia after oral inoculation with type la group B Streptococcus. An effect of ampicillin-sulbactam was evident as early as 2 hours but maximal 3 to 5 hours after injection.
我们的目的是评估母体给予氨苄西林-舒巴坦对新生兔B族链球菌定植和菌血症的影响。
在诱导分娩前，妊娠31天、处于第29天的新西兰白兔在分娩前2至8小时接受单剂量50mg/kg氨苄西林-舒巴坦肌肉注射或不接受治疗。用催产素诱导分娩。分娩后，每只幼崽的口咽部接种10(9)cfu的Ia型B族链球菌。每天从每只幼崽的口咽部和肛门直肠采集培养物，并在死亡时或96小时后从心脏采集培养物。在分娩时测定母体和幼崽体内的氨苄西林-舒巴坦浓度。
13只动物被分配至不接受治疗组，14只动物被分配至氨苄西林-舒巴坦治疗组。未治疗的幼崽在24小时时口咽部定植率为100%。与未治疗的幼崽相比，接受抗生素治疗的幼崽在出生后24小时和48小时口咽部培养呈阳性的可能性显著降低（24小时时分别为47%对100%，p<0.0001；48小时时分别为68%对91%，p=0.0006）。对于肛门直肠培养，接受治疗的幼崽培养结果呈阳性的可能性显著降低。在48小时和72小时时，接受治疗的动物心脏培养呈阳性的可能性也低于未治疗的动物（48小时时分别为30%对96%，p=0.0001；72小时时分别为31%对71%，p=0.其作用最早在注射后2小时出现，但在3至5小时达到最大。5）。接受治疗的幼崽在48小时时的存活率更高（89%对62%，p<0.0001）。当比较出生后24小时的新生儿口咽部定植情况与母体抗生素注射至分娩的时间长度时，存在显著的多项式关系（r=0.78，p<0.05）。氨苄西林-舒巴坦血清浓度在注射后3至5小时最高。出生后24小时新生儿B族链球菌口咽部定植率与出生时新生儿氨苄西林血清浓度之间存在负相关（r=0.733）。
单次肌肉注射氨苄西林-舒巴坦进行经胎盘治疗可显著降低口服接种Ia型B族链球菌后新生儿的定植和菌血症。氨苄西林-舒巴坦的作用最早在注射后2小时出现，但在3至5小时达到最大。
