Puerperal infection in the antibiotic era

A randomized trial of penicillin and streptomycin in the prevention of post-partum infection in Uganda

We report findings of a randomized trial of penicillin and streptomycin to prevent post-partum infection conducted on 737 women who delivered consecutively at Kawempe Maternity Centre (KMC) in Kampala from 1st October, 1989 to 31st May, 1990. The objectives were: (i) to identify clinical post-partum infection using at least two of its symptoms and signs (fever, lower abdominal pain, lower abdominal tenderness, vaginal discharge); (ii) to identify the causes of post-partum infection using laboratory methods; and (iii) evaluate the effectiveness of prophylactic fortified procaine penicillin (PPF) and streptomycin on post-partum infection. Clinical infection occurred in 36.4% of the group not given antibiotics, 23.3% in the PPF group and 20.3% in the streptomycin group. Laboratory-confirmed infection occurred in 15.5% of the group not given antibiotics, 9.2% in the PPF group and 8.4% in the streptomycin group. However, severe laboratory-confirmed infection (severe clinical infection plus positive laboratory findings) occurred in 4.9% of the group not given antibiotics, 6.1% in the PPF group and 6.6% in the streptomycin group. In general, the organisms isolated included enterobacteria (35.9%), yeast and protozoa (31.6%), staphylococci (23.9%), streptococci (69%) and Neisseria (1.7%). The advantage of PPF and streptomycin was evident in most subgroups defined by clinical characteristics or laboratory findings. In view of the findings in this study, we believe that prophylactic antibiotics given in labor may have a role to play at reducing the incidence of post-partum infection. However, as the cost of antibiotics in developing countries is significant, the development of resistant organisms due to indiscriminate antibiotic use is also a concern and health resources are best used when targeted at specific populations, we feel that antibiotic prophylaxis should not be used routinely and that a more realistic view can be obtained by studying high-risk groups of women with more severe infection.

Obstetric infection control in a developing country

In Ghana, infection has been identified as a major cause of birth-related mortality. Results of a 2-month observation of infection control practices among Ghanaian obstetric nurses and midwives indicated that most personnel did not practice basic rules of asepsis. Problems included frequent breaks in technique, inadequate sterilization and disinfection, and repeated exposure to large amounts of blood and vaginal secretions. Supplies were limited and, even when available, not always used appropriately. The situation in developing countries is different from that in the United States. Therefore, an observational needs assessment is essential to plan relevant and practical measures for change.

Suspected postpartum endometritis: a controlled clinical trial of single-agent antibiotic therapy with Amox-CA (Augmentin) vs. ampicillin-metronidazole +/- aminoglycoside

Endometritis is the commonest postpartum complication and is one of the leading causes of maternal morbidity, if not mortality. The object of the present clinical trial was to assess the efficiency of single-agent therapy with Amox-CA (Augmentin) (formulation which includes a beta-lactamase inhibitor), against standard treatment which necessarily combines two or three antibiotics depending on the clinical severity of the case. 101 patients were evaluated in this comparative prospective randomized study. The mild forms were defined by a temperature between 37.9 and 38.4 degrees C and the severe forms by a temperature of more than 38.5 degrees C (which alone required treatment with three antibiotics). The time until the return of apyrexia and the clinical cure rate, as well as duration of treatment, were identical in both groups. Tolerance was good: no side effect requiring discontinuation of treatment occurred. In the population value, the use of a single-agent therapy with amoxycillin/clavulanic acid is not significantly different from a double or triple-agent regimen, and the convenience is increase.

A randomized clinical trial of antibiotic prophylaxis in cesarean section: maternal morbidity, risk factors and bacteriological changes

In the United States, several well-designed studies have demonstrated the efficacy of short-course antibiotic prophylaxis in cesarean sections. The present prospective study was conducted on 150 patients in a Dutch university hospital in a randomized double-blind fashion. Cefoxitin was administered according to a three-dose, 12 h regimen, the first injection given immediately after clamping of the umbilical cord. The rate of infection among the patients was significantly reduced by prophylaxis, judging from febrile morbidity, endometritis, wound infections, urinary tract infections and need for postoperative antibiotic therapy. The prophylactic use of the cefoxitin was especially effective in the secondary cesarean section population. Three risk factors significantly correlated with increased risk of infection: labor, rupture of membranes and pelvic examination. Postoperative cervical cultures showed a significant reduction of bacteria in the cefoxitin group. No shift towards resistant pathogens was demonstrable.

Evidence for the non-infectious etiology of early postoperative fever

In a prospective study of infections in 871 general surgery patients, we identified 81 patients who developed unexplained postoperative fevers. The majority of these episodes (72%) occurred early (within the first 48 hours) following surgery. Patients who developed early, unexplained fevers differed significantly from patients who developed documented postoperative infections. Patients with unexplained fevers were younger, had less severe underlying disease and underwent less extensive surgeries than patients who subsequently developed infections. In these respects, they were more similar to non-infected, non-febrile patients. We concluded that episodes of early, unexplained postoperative fever occur frequently in a wide range of general surgery patients. Most of these episodes are non-infectious in origin. Patients with early postoperative fevers should be evaluated to identify any obvious sources of infection. If no focus is identified, empiric antibiotic therapy should not be initiated nor should prophylactic antibiotics be extended for prolonged durations. Unexplained fevers will resolve in time without specific therapeutic interventions.

Risk factors for postcesarean endomyometritis

Postcesarean endomyometritis is the most common nosocomial infection treated by obstetrician-gynecologists. One important prevention strategy is the use of perioperative antibiotic prophylaxis initiated after occlusion of the umbilical cord for parturient patients with a high risk of this infection. However, the identification of these high risk patients remains problematic. Numerous clinical risk factors have been identified in the literature. Important intrinsic risk factors include indigent socioeconomic status, anemia, and preterm gestational age at the time of cesarean section. The three most consistently identified extrinsic risk factors include labor prior to cesarean section, the duration of ruptured chorioamniotic membranes, and the number of preoperative vaginal examinations. Alternatively, many investigators have attempted to define high-risk patients utilizing various laboratory tests, such as Gram staining or bacterial culture of amniotic fluid, chorioamniotic membranes, or endometrial biopsy specimens; although specific, these tests have not been sufficiently sensitive predictors of infection. Currently, assessment of the duration of ruptured membranes and length of labor remain the most sensitive, readily available, and therefore clinically useful predictors of postcesarean endomyometritis.

Puerperal and perinatal infections with group B streptococci

Twenty-one patients were seen with puerperal sepsis owing to group B streptococci (GBS), resulting in an attack rate of 2/1,000 deliveries. Most were young primiparous black women from a population with a known high incidence of GBS carriage. The association among abdominal delivery, endometritis, and puerperal sepsis was striking. Cultures of the birth canal or lochia were commonly positive for the same serotype recovered from the blood. Forty-seven patients with nonbacteremic GBS infections were seen; 27 had endometritis or amnionitis. Twenty patients had GBS urinary tract infection: Eight infections occurred prenatally, seven at delivery, and five post partum. Seven neonates developed serious GBS infections; intrauterine exposure occurred in at least four cases. Fetal exposure to GBS also occurred in three of four cases in which parturients with GBS bacteremia were delivered of their infants by cesarean section. Because of the high incidence of puerperal and perinatal GBS infections in this population, antibiotic prophylaxis regimens may be beneficial.

A comparative study of two antibiotic regimens for the treatment of operative site infections

This prospective study was designed to compare the relative efficacy of two antibiotic regimens for the treatment of operative site infections subsequent to pelvic operations. Patients with endomyoparametritis after delivery or pelvic cellulitis subsequent to hysterectomy were randomized to treatment with the combination of penicillin-gentamicin or the single agent cefoxitin. Seventeen of the 26 patients (65%) with endomyoparametritis who were treated with penicillin-gentamicin were cured by antibiotic therapy alone, in comparison to 15 of 23 (65%) patients treated with cefoxitin. Fifty-eight percent of the patients with pelvic cellulitis who were treated with penicillin-gentamicin responded favorably, in comparison to 50% of the patients treated with cefoxitin. None of these differences was statistically significant. In this study, neither antibiotic regimen provided satisfactory initial treatment for surgically induced soft tissue pelvic infection. Moreover, 11 of the 28 patients with treatment failures (40%) developed serious sequelae of their primary infection.

A prospective study of group B streptococcal bacteriuria in pregnancy

Bacteriuria in pregnancy was prospectively studied in 569 women, with specific reference to group B streptococcal infection. Forty-six patients (8%) had bacteriuria, including 14 with group B streptococcal infection; group B streptococci (GBS) were exceeded in frequency only by Escherichia coli. Two thirds of the bacteriuric patients remained asymptomatic. The outcome of pregnancy was studied in 41/46 bacteriuric patients, including all those with group B streptococcal infection. Two pregnancies ended in intrauterine fetal death, and one neonate developed group B streptococcal sepsis; all three complications occurred in the 14 women with group B streptococcal bacteriuria. Diabetes mellitus appeared to increase the risk of group B streptococcal bacteriuria. This study revealed that group B streptococcal bacteriuria is more common in pregnancy than was previously suspected and suggests that culture methods to detect GBS should be used in bacteriuria screening programs done in pregnancy. In terms of perinatal infection risk, screening for group B streptococcal bacteriuria at or near the time of delivery may be more meaningful than other group B streptococcal surveillance culture studies.

Evaluation of cefoxitin prophylaxis for cesarean section

Prophylactic cefoxitin was evaluated in 101 patients undergoing cesarean section. A three-dose regimen of either cefoxitin or placebo was administered randomly in a double-blind manner, 46 patients receiving cefoxitin and 55 placebo, with the first dose given after the cord was clamped. In the placebo group, 29% of the patients developed pelvic or wound infection, compared to 4% in the cefoxitin group (P less than 0.003). No patient required re-operation, re-admission, or had a life threatening infection. Ten risk factors for infection were analyzed to help ascertain which patients would benefit from prophylaxis. Cefoxitin, with a broad spectrum of aerobic and anaerobic coverage, was found to be an effective and safe prophylactic agent when given to all patients undergoing cesarean section.

Infection with Mycoplasma hominis in postpartum fever

A follow-up of 535 patients after vaginal delivery showed that 9% had a fever of 37.7 degrees C or greater, and 2% had a fever of 38 degrees C or more, on two days. The commonest cause of both categories of fever was Mycoplasma hominis infection as defined by a fourfold or greater rise in mycoplasmacidal antibody titre. Among women for whom sera were available this agent caused 50% (14/28) of all fevers and 71% (5/7) of the higher fevers. Absence or low titre (< 1:8) of antibody against M. hominis was the strongest single predictor of otherwise unexplained fever (16/40 patients with low antibody titre were febrile vs 7/50 with high antibody titre, p < 0.01). Among women with absent or low antibody titres, both rise in titre of antibody to this organism and lochial colonisation by it were significantly associated with fever (p < 0.001, p < 0.025, respectively). Standard microbiological and clinical techniques identified probable causes in only 18% (5/28) of all fevers and 29% (2/7) of higher fevers. Patients who had postpartum infection caused by M. hominis remained in hospital 31% longer than the non-infected patients (4.57 vs 3.49 days, p < 0.001). Low antibody to and lochial colonisation with M. hominis occurred together in 17% of patients, who accounted for 71% of all higher fevers. Since these risk factors for postpartum fever can be identified before delivery, prophylactic measures applied selectively to women with these risk factors may prevent a large proportion of postpartum fevers and the excess hospital stay associated with them.

Puerperal infectious morbidity: relationship to route of delivery and to antepartum Chlamydia trachomatis infection

We investigated the relationship of route of delivery and of antepartum Chlamydia trachomatis cervical infection to selected forms of puerperal infectious morbidity, including intrapartum fever, or early (less than 48 hours) postpartum fever not attributable to infections of sites outside the uterus and late (48 hours to 6 weeks) postpartum endometritis. Infectious morbidity occurred in 27 (44%) of 62 women who underwent cesarean section and in 33 (10%) of 329 who underwent vaginal delivery (p less than 0.001). Postsection infectious morbidity was not correlated with C. trachomatis infection and was largely limited to early postpartum fever. Among women who underwent vaginal delivery, infectious morbidity occurred in 10 (34%) of 29 women with and in 23 (8%) of 300 without C. trachomatis infection (p less than 0.001), and chlamydial infection was associated only with intrapartum fever and late postpartum endometritis. Separate matched case-control analyses confirmed that cesarean section was associated with an increased risk of early postpartum fever (p = 4 x 10(-8)); whereas among women who underwent vaginal delivery, antepartum C trachomatis infection was associated with an increased risk of development of intrapartum fever or late postpartum endometritis (p = 0.002).

Determinants of postpartum morbidity in laboring monitored patients: a reassessment of the bacteriology of the amniotic fluid during labor

Identification of the type and concentration of bacterial organisms in the amniotic fluid (AF) during labor might allow for earlier and more effective treatment of postpartum infections. Previous studies have identified organisms typically associated with postpartum endometritis, but the relationship to intrapartum findings has been disappointing. The purpose of this prospective study was to reassess any relationships between the bacteriology of the AF during labor and the postpartum course in the high-risk, noninfected, monitored gravid patient. The intrapartum AF bacterial flora was similar in 70 patients delivered vaginally and 80 patients delivered abdominally. In patients who did not receive prophylactic antibiotics, a total AF organism count of greater than or equal to 10(4) colonies/ml and the presence of any streptococcal or Bacteroides organism, gram-negative bacillus, or Staphylococcus aureus were significantly related to postpartum morbidity. Under these conditions, cesarean section considerably increased the risk of clinical endometritis. These results suggest that semiquantitative culture of AF obtained through the intrauterine pressure catheter prior to delivery may be of value in the postpartum management of patients delivered by cesarean section.

Infectious morbidity after primary cesarean sections in a private institution

Primary cesarean sections were performed on 395 patients between January 1, and December 31, 1976. A retrospective review of 322 of these patients indicated that the incidence of postoperative intrauterine infection was the same in both monitored and nonmonitored patients. The incidence of postoperative intrauterine infections was not significantly related to ruptured membranes or the duration of ruptured membranes. The most significant factor associated with postoperative morbidity was the type of anesthesia.