Molecular Characterization and Antibiotic Resistance Profile of Staphylococcus haemolyticus in Pregnant Women with Urinary Tract Infections

Background and Aim: Staphylococcus haemolyticus is a prominent pathogen in hospital-related infections, exhibiting high antibiotic resistance. This study aimed to investigate antibiotic sensitivity, biofilm formation, and the presence of virulence-associated genes in S. haemolyticus isolated from pregnant women with urinary tract infections. Materials and Methods: Clinical samples were collected from pregnant women with urinary tract infections between October 2021 and December 2022. S. haemolyticus isolates were identified using cultural, biochemical, and molecular methods. Antibiotic susceptibility was determined using the VITEK-2 system. Biofilm formation was assessed, and virulence-associated genes (hla, hlb, fnbA, and fnbB) were detected using PCR. Results: Among 260 clinical samples, 36 S. haemolyticus isolates were identified. The isolates exhibited high resistance to Benzylpencillin, Erythromycin, oxacillin, Trimethoprim/sulfamethoxazole, Levofloxacin, and Gentamicin. Resistance was lower to Tigecycline, linezolid, tobramycin, Rifampin, vancomycin, Moxifloxacin, Tetracycline, and Ticoplanin. Biofilm formation was negative in 69.4% and weak in 30.6% of isolates. The hla gene was present in all isolates, while hlb was detected in 77.7%. Detection rates of fnbA and fnbB were 88.8% and 38.8%, respectively. Conclusion: This study highlights the high antibiotic resistance, limited biofilm formation ability, and prevalence of virulence-associated genes in S. haemolyticus isolates from pregnant women with urinary tract infections. These findings underscore the clinical significance of this bacterium and the need for infection control measures.