Distribution and antimicrobial susceptibility profiles of bacterial isolates from vaginal discharge specimens among hospitalized patients in a tertiary maternal and child healthcare hospital in Shenzhen, China

Introduction Abnormal vaginal discharge is a common and clinically important presenting complaint and reason for specimen submission, often suggesting lower genital tract disorders such as vaginal infections, and may adversely affect women’s reproductive health and pregnancy outcomes. This study aimed to investigate the distribution and antimicrobial susceptibility profiles of common bacteria isolated from vaginal discharge specimens submitted from hospitalized patients at Longgang District Maternity & Child Healthcare Hospital of Shenzhen City, in order to provide a reference for the interpretation of clinical specimen results and empirical antimicrobial therapy. Methods Non-duplicate bacterial isolates recovered from vaginal discharge specimens collected from hospitalized patients between January 1, 2021 and December 31, 2025 were retrospectively analyzed, and the composition of common vaginal bacterial isolates, the age distribution of patients, and the antimicrobial susceptibility profiles of major isolates to commonly used antibiotics were assessed. Results A total of 1,094 non-duplicate positive bacterial isolates were identified during 2021–2025, with Gram-positive bacteria predominating (65.2%). The major isolates were Streptococcus agalactiae , Escherichia coli , and Klebsiella pneumoniae subsp. pneumoniae . Most cases were from the obstetrics department, and the majority of patients were women aged 25–34 years. Antimicrobial susceptibility testing showed marked differences in antimicrobial susceptibility profiles among bacterial species: Streptococcus agalactiae remained highly susceptible to penicillins and vancomycin, but showed high resistance rates to clindamycin and tetracycline; Escherichia coli and Klebsiella pneumoniae subsp. pneumoniae had relatively high rates of extended-spectrum β-lactamase (ESBL) positivity, while remaining highly susceptible to amikacin, carbapenems, and tigecycline; some isolates also exhibited notable resistance to trimethoprim-sulfamethoxazole, fluoroquinolones, and certain β-lactam antibiotics. Discussion Vaginal bacterial isolates from hospitalized patients were predominantly composed of Streptococcus agalactiae and members of the Enterobacteriaceae family, and were mainly derived from the obstetrics department and women of reproductive age. Marked differences in antimicrobial susceptibility profiles were observed among bacterial species, suggesting that maternal and child healthcare hospitals should strengthen local surveillance of isolate distribution and antimicrobial susceptibility in order to support more precise empirical therapy and antimicrobial stewardship.