Antibiotic therapy reduces preterm birth complications and improve neonatal outcome

USA: Intravenous therapy with the antibiotic clarithromycin may reduce the intraamniotic inflammatory response in patients with preterm prelabour rupture of the membranes (PPROM) having either intraamniotic infection or sterile intraamniotic inflammation, finds a recent study.

Results of the study, published in the American Journal of Obstetrics and Gynecology, further found that clarithromycin treatment was associated with a reduction in a load of Ureaplasma spp DNA in the amniotic fluid of patients with PPROM <34 weeks of gestation.

PPROM is frequently complicated by intraamniotic inflammatory processes such as intraamniotic infection and sterile intraamniotic inflammation. Antibiotic therapy is recommended to PPROM patients in order to prolong the interval between this complication and delivery, improve neonatal outcome, and reduce the risk of clinical chorioamnionitis. However, information is lacking on whether antibiotics administration reduces the intensity of the intraamniotic inflammatory response or eradicate microorganisms in PPROM patients.

Marian Kacerovsky, Wayne State University School of Medicine, Detroit, MI, and colleagues conducted the study to determine whether 1) antimicrobial agents can reduce the magnitude of the intraamniotic inflammatory response in patients with PPROM by assessing the concentrations of interleukin-6 in amniotic fluid before and after antibiotic treatment and whether 2) treatment with intravenous clarithromycin changes the microbial load of Ureaplasma spp DNA in amniotic fluid.

The researchers conducted a retrospective cohort study that included patients having (1) a singleton gestation, (2) PPROM between 24+0 and 33+6 weeks, (3) a transabdominal amniocentesis at the time of admission, and (4) intravenous antibiotic treatment (clarithromycin for patients with intraamniotic inflammation and benzylpenicillin/clindamycin in the cases of allergy in patients without intraamniotic inflammation) for 7 days. They performed follow-up amniocenteses (7th day after admission) in the subset of patients with a latency period lasting longer than 7 days

Concentrations of interleukin-6 were measured in the samples of amniotic fluid with a bedside test, and the presence of microbial invasion of the amniotic cavity was assessed with culture and molecular microbiological methods. Intraamniotic inflammation was defined as a bedside interleukin-6 concentration ≥745 pg/mL in the samples of amniotic fluid. Intraamniotic infection was defined as the presence of both microbial invasion of the amniotic cavity and intraamniotic inflammation; sterile intraamniotic inflammation was defined as the presence of intraamniotic inflammation without microbial invasion of the amniotic cavity.

A total of 270 patients with PPROM were included in this study: 207 patients delivered within 7 days and 63 patients delivered after 7 days of admission. Of the 63 patients who delivered after 7 days following the initial amniocentesis, 40 underwent a follow-up amniocentesis. Patients with intraamniotic infection (n = 7) and sterile intraamniotic inflammation (n = 7) were treated with intravenous clarithromycin. Patients without either microbial invasion of the amniotic cavity or intraamniotic inflammation (n = 26) were treated with benzylpenicillin or clindamycin. 

The study, "Antibiotic administration reduces the rate of intraamniotic inflammation in preterm prelabor rupture of the membranes," was published in the American Journal of Obstetrics and Gynecology.

DOI: https://doi.org/10.1016/j.ajog.2020.01.043