Bacterial Vaginosis and Its Relation to Caesarean Wound Infection

INTRODUCTION

Bacterial vaginosis (BV) is a prevalent female condition, with roughly one-third of females aged 14 to 49 screening positive for BV. BV is found in a comparable percentage of postmenopausal females. ¹

BV is the most common cause of vaginal secretions or malodor among women seeking care; however, the majority of females with BV are asymptomatic. Aside from the discomfort, BV is linked to a number of negative consequences. Untreated BV is linked to subsequent sexually transmitted infections (STIs). STIs related to BV infection include Trichomonas vaginalis, Chlamydia trachomatis, Neisseria gonorrhoeae, and herpes simplex virus infection. ²

When it comes to pregnancy, BV was linked to a higher likelihood of developing intrapartum chorioamnionitis, a known risk factor for postpartum endometritis. BV has also been linked to post-cesarean endometritis, with BV microorganisms being isolated in the endometrial cavities of such

women.³ Presurgical intravaginal metronidazole gel administration minimizes the chances of post-cesarean endometritis by 58 % in women who underwent caesarean birth ⁴.

In women who have had an early pregnancy terminated, presurgical BV therapy can lower the risk of infection. In one study, women who had presurgical BV had a 6-fold increased incidence of postorbital endometritis.⁵ In randomized controlled studies of women who had BV after having first-trimester abortions, women who had metronidazole or clindamycin prior to surgery had rates of infection that were 3-to 4-fold less. Perioperative metronidazole therapy was also reported to be an  efficient choice for women having BV who are having an abortion, reducing the risk of postprocedural upper genital tract infections by about half. ⁶

Preoperative BV treatment must focus on efficacy, adherence, and, in some patients, therapy length. One of the traditional benefits of single-dose treatment is that patients' adherence is nearly guaranteed. Preoperative BV therapy has the additional benefit of treating BV as soon as possible before a scheduled operation date. ¹

The purpose of the research was to examine the relationship between bacterial vaginosis and caesarean wound infection.

PATIENTS AND METHODS

This is a prospective research that was performed on a total of 200 pregnant women prepared for elective emergency cesarean section and was conducted in the Obstetrics & Gynecology department, Al-Materia Teaching Hospital, Cairo, Egypt, to study if intermediate or definite phases of BV represent hazard factors for postsurgical wound infection following caesarean section starting from October 2020 to August 2021.

Pregnant women with the following criteria were included in the study scheduled to undergo elective cesarean section and age between 22 and 35 years. While patients with medical disorder e.g., Diabetes…. etc., twins and history of treatment of bacterial vaginosis or vaginal therapy were excluded from the study.

The study involved 200 women who were pregnant and were split into two groups: Group I: included 100 pregnant with positive bacterial vaginosis and Group II: included 100 pregnant with negative bacterial vaginosis.

Study procedure: All patients in this research gave their informed consent and were submitted to a thorough clinical examination that included a full history as well as general, abdominal, and pelvic exams. History taking: including (personal history, age, obstetric history, medical history, surgical history, past history and family history). Clinical exams include general, abdominal, and pelvic exams. Investigations: including (labs; CBC, blood group, liver and kidney functions, coagulation profile & imaging; 2D obstetric ultrasound).

Prior to surgery, vaginal cultures have been acquired for pregnant women having a caesarean section. To maintain confidentiality, every patient has only been identified using a code. Vaginal swabs have been rolled onto glass slides right away by making vaginal smears, which have been Gram-stained and scored using the Nugent technique.

 The Nugent approach involved scoring the general character of the vaginal flora by examining bacterial morphotypes under a microscope. Nugent scores vary from 0 to 10, depending on the predominance of three bacterial morphotypes, which approximately correlate to Lactobacillus, G. vaginalis or Mobiluncus, and Bacteroides.

The amount of long rod-shaped Gram-positive bacilli has been rated 0-4, with 0 indicating a large number of Lactobacillus; small Gram negative and Gram-variable rods and coccobacilli (Bacteroides and G. vaginalis) have been rated 0-4, with 4 indicating the greatest recorded quantity of such bacteria; and curved rods (for example, Mobiluncus spp.) are rated 0-2, with 2 indicating the greatest recorded numbers. All swabs have been rolled by the same technician, and all slides have been stained and scored by the same technician, to guarantee consistency in the vaginal fluid amount on every slide, as well as Gram-staining and Nugent scoring.  Cesarean section wound followed after operation to identify of the sepsis of the wound. Septic wound was render to culture and sensitivity to identify the causative organism and proper treatment.

Statistical analysis: IBM SPSS statistics (Statistical Package for Social Sciences) software version 22.0, IBM Corp., Chicago, USA, 2013, has been employed to code, tabulate, and statistically analyze the obtained data. Following checking for normality with the Shapiro-Wilk test, quantitative normally distributed data is reported as mean±SD (standard deviation), and if the data is normally distributed, it is then compared using an independent t-test. Qualitative data is expressed as numbers and percentages for variables with small anticipated quantities, and the Chi-square test and Fisher's exact test are employed to compare them. If the P value was less than 0.050, it was considered significant; otherwise, it was considered non-significant. Relative Rate= Bacterial vaginosis Rate / Control Rate.

RESULTS

BMI: Body mass index. GA: Gestational age. ^Independent t-test. #Chi square test

Table 1: Characteristics of the studied groups' demographics

Table (1) reveals that there were no significant differences in age, BMI, parity, previous caesarean section, or gestational age across the groups studied.

^Independent t-test. #Chi square test

Table 2: Characteristics of the studied groups' operations

Table (2) reveals that there are no statistically significant differences between the studied groups in terms of operation indication, duration and blood loss.

#Chi square test. *Significant. RR: Relative rate. CI: Confidence interval.

Table 3: Cesarean wound infection in the study groups

Table (3) demonstrates that cesarean wound infection was significantly more frequent in the bacterial vaginosis group.

#Chi square test. *Significant. RR: Relative rate. CI: Confidence interval.

Table 4: Cesarean wound infection time among the studied groups

Table (4) shows that cesarean wound infection within one week was significantly more frequent among bacterial vaginosis group.

§Fisher’s Exact test. *Significant. RR: Relative rate. CI: Confidence interval.

Table (5): Readmission due to cesarean wound infection in the study groups

Table (5) demonstrates that readmission due to cesarean wound infection was significantly more frequent among bacterial vaginosis group.