# Distribution and antimicrobial resistance profiles of common blood culture isolates in a maternal and child health specialty hospital, Shenzhen (January 2021–October 2025), China

## TL;DR

This study analyzed blood culture isolates from a maternal and child health hospital in China to track infection-causing bacteria and their resistance to antibiotics.

## Contribution

The study provides updated data on antimicrobial resistance patterns in a specialized hospital setting, highlighting emerging resistance risks.

## Key findings

- Coagulase-negative staphylococci were the most common isolates, but many were likely contaminants.
- Escherichia coli showed high ESBL rates and one carbapenem-resistant isolate was identified.
- MRSA was detected but remained fully susceptible to glycopeptides like vancomycin.

## Abstract

To investigate the distribution and antimicrobial resistance profiles of pathogens causing bloodstream infections (BSIs) in a maternal and child health hospital, providing evidence for rational clinical therapy.

A retrospective analysis was conducted on 395 bacterial isolates recovered from positive blood cultures of inpatients at Longgang District Maternity & Child Healthcare Hospital of Shenzhen City between January 1, 2021 and October 31, 2025. Duplicate isolates from the same patient were excluded.

Among all isolates, Gram-positive bacteria accounted for 60.5% and Gram-negative bacteria for 39.5%. Coagulase-negative staphylococci (40.3%) were the most frequently detected, although many were likely contaminants. The major clinically relevant pathogens were Escherichia coli (28.6%), Streptococcus agalactiae (3.3%), Klebsiella pneumoniae subsp. pneumoniae (2.8%), and Staphylococcus aureus (2.3%). Escherichia coli showed a 44.3% Extended-Spectrum β-Lactamase (ESBL)-positive rate and elevated resistance to third-generation cephalosporins, with one carbapenem-resistant Enterobacteriaceae (CRE) isolate identified. Klebsiella pneumoniae exhibited overall low resistance levels. Among Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA) accounted for 22.2%, all susceptible to vancomycin, linezolid, and tigecycline. Streptococcus agalactiae retained excellent β-lactam and glycopeptide susceptibility, whereas Streptococcus pneumoniae exhibited pronounced macrolide resistance.

Escherichia coli and Staphylococcus aureus were the leading pathogens. The high ESBL rate in Escherichia coli and the detection of a CRE isolate indicate emerging β-lactam resistance risks. Although MRSA was detected, complete susceptibility to glycopeptides was preserved, highlighting the importance of ongoing monitoring.