Resistance Rates of Streptococcus agalactiae Strains Isolated from Urine Samples to Various Antibiotics

Abstract

Aim: Group B Streptococcus (GBS), also known as Streptococcus agalactiae, are Gram-positive, encapsulated bacteria found in the normal human gastrointestinal and urogenital flora. A wide variety of infectious diseases can cause urogenital system infections in newborns, elderly people, immunocompromised people, pregnant women, and adults. In this study, we aimed to inform clinicians about the agents that can be used in intrapartum antibiotic prophylaxis by examining the antibiotic susceptibility of GBS strains isolated from urine samples from the Gynecology and Obstetrics Clinic in our laboratory.
 Material and Methods: Isolates of the S. agalactiae isolated from a total of 222 urine samples from the Gynecology and Obstetrics Clinic that came to our Medical Microbiology laboratory between January 2022 and December 2022 were included and the data of these isolates were evaluated retrospectively. The clinical samples that came to our laboratory were inoculated on Sheep blood agar medium and incubated at 37°C for 18-24 hours. Quantitatively seeded urine culture ≥104 CFU/ml grown bacteria was considered a uropathogenic. Urogenital skin flora element or three and more different types of bacteria growing cultures as contamination evaluated. 
 Results: Due to the group selected as the sample, 100% of the patients were female. The age range of the patients ranged from 12 to 72, and the mean age was calculated as 30.16. All GBS isolates were susceptible to penicillin, linezolid, trimethoprim-sulfamethoxazole, tigecycline, teicoplanin, and vancomycin. 
 Conclusion: Penicillin resistance was not found in our study. However, resistant strains were detected in erythromycin, clindamycin, and levofloxacin, which stand out as other options in cases where penicillin cannot be used.