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Objective: This study assessed the antibiotic susceptibility and characterized antibiotic resistance genes of group B Streptococcus (GBS) isolates from selected tertiary care hospitals in Western Province, Sri Lanka., Methods: A descriptive cross-sectional study was carried out to determine antibiotic sensitivity of GBS among 175 pregnant women of >35 weeks of gestation attending antenatal clinics in four teaching hospitals. Low vaginal and rectal swabs were collected separately, and GBS was identified by standard microbiological methods. Antibiotic sensitivity and minimum inhibitory concentration (MIC) were performed according to Clinical and Laboratory Standards Institute (CLSI) guidelines. DNA was extracted from culture isolates, and antibiotic-resistant genes were identified by polymerase chain reaction using ermB, ermTR, mefA, and linB genes., Results: GBS colonization in the study sample was 25.7% (45/175) with detection rate of 22.9% (40/175) and 2.9% (5/175) in vaginal and rectal samples, respectively. All isolates were susceptible to penicillin with an MIC range of 0.03-0.12 μg/mL. Six isolates (13.3%) were intermediate, and 11 isolates (24.4%) were resistant to erythromycin. There were 5 intermediately resistant isolates (11.1%) and 10 resistant isolates (22.2%) for clindamycin. Of them, seven had inducible clindamycin resistance (iMLSB). MIC range of erythromycin was 0.03-0.32 μg/mL and that of clindamycin was 0.06-0.32 μg/mL. ermB gene was detected in 7 (15.5%). ermTR gene was found in 16 (35.6%) and was significantly associated with iMLSB phenotype (p = 0.005). mefA gene was detected in two (4.4%) isolates, while linB gene was not detected in tested isolates., Conclusion: All isolates were sensitive to penicillin, and the most prevalent resistance genotype was ermTR in the study population., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

The proportion of Group B Streptococcus (GBS) colonisation in pregnant women >35 weeks of gestation was 18% and 49% by culture and real-time PCR respectively in selected hospitals from the Western Province of Sri Lanka. A Descriptive cross-sectional study was conducted from January to April 2019. Two low vaginal and rectal swabs were collected from 100 pregnant women. Identification of GBS was done by culture and real-time PCR. GBS isolates were found to be sensitive to penicillin, ampicillin, cefotaxime, vancomycin, while 5 and 4 isolates out of 18 were resistant to erythromycin and clindamycin, respectively. Further, there was a significant association between GBS colonisation and a history of vaginal discharge and unemployment.IMPACT STATEMENT What is already known on this subject? Prevalence of GBS colonisation in the vagina and rectum of pregnant women in developing countries ranges from 8.5% to 22%. The Conventional method of culture has been considered the gold standard for diagnosis, however, the culture method does not give positive results for all cases of GBS. Polymerase chain reaction (PCR) has been found to be more sensitive for the detection of GBS than culture. In Sri Lanka, ante-natal screening for GBS is not practiced as the prevalence of GBS is still unlcear due to non-availably of data. Only a few scattered studies have been conducted using culture in Sri Lanka. Thus there is an urgent need to determine the magnitude of the GBS colonisers of ante-natal women in order to set up guidelines for screening and management of GBS. What do the results of this study add? In this study, the overall GBS colonisation rate which was detected using both culture and PCR was 50% in Western Province of Sri Lanka. That was a high figure when compared to the figures which were detected previously in Sri Lanka using only conventional culture methods. The risk factors for GBS colonisation were found to have a significant relationship with the history of abnormal vaginal discharge. Further, it was found that when Candida species coexisted with GBS, the existence of GBS was enhanced. Penicillin remains the antibiotic of choice for GBS. What are the implications of these findings for clinical practice and/or further research? This study emphasises the importance of establishing national policies for screening of pregnant women of >35 weeks of gestation to reduce the risk of neonatal infection. Further, it gives an insight into the options of antibiotics that can be used for treatment of these GBS colonisers from Sri Lanka.

Objective: Antiseptics are widely used in wound management to prevent or treat wound infections due to their proven wound healing properties regardless of their cytotoxicity. The objective of this study was to determine the bactericidal effects of three antiseptics on pathogens known to cause wound infections., Method: The study was carried out at a tertiary care hospital and a university microbiology laboratory in Sri Lanka in 2013. The three acids (acetic acid, ascorbic acid and boric acid) in increasing concentration (0.5%, 0.75% and 1%) were tested against bacterial suspensions equivalent to 0.5 McFarland standard. The Bacteria isolates used were isolated from wound and standard strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa., Results: There were 33 (68.8%) Coliforms, 10 (20.8%) Pseudomonas species, and 5 (10.4%) strains of Staphylococcus aureus. Acetic acid at concentration of 0.5% inhibited growth of 37 (77%) and 42 (87.5%) of tested isolates when exposed for 30 and 60 minutes, respectively. However 100% inhibition was achieved at four hours. At a concentration of 0.75%, 40 (83.3%) and 44 (91.7%) were inhibited when exposed for 30 and 60 minutes, respectively, with 100% inhibition at 4 hours. At concentration of 1%, 46 (95.8%) inhibition was seen at 30 minutes and 100% inhibition at 60 minutes. Ascorbic acid, at 0.5% and 0.75 % concentrations, inhibited growth of 45(93.7%) and 47(97.9%) of isolates respectively when exposed for 30 minutes. At these two concentrations, 100% inhibition was achieved when exposed for one hour. At 1% concentration, 100% inhibition was achieved at 30 minutes. Boric acid did not show bactericidal effect at concentrations of 0.5%, 0.75 % and 1%. Pseudomonas species were inhibited at 30 minutes by 0.5% acetic acid. Bactericidal effect against all the standard strains was seen with three acids at each concentration tested from 30 minutes onwards, Conclusion: Ascorbic acid was bactericidal for all organisms tested within the shortest exposure time at the lowest concentration compared to other two acids. Despite promising bactericidal effects, further studies warrant, as ongoing debates on toxicity of acids on tissue epithelialisation. Application of antiseptics for a shorter duration could overcome this problem without losing bactericidal activity., Declaration of Interest: The authors have no conflict of interest and no funding was received for this study.