AUTHOR=Wang Ying , Liu Chao , Xia Wenbo , Cui Yanxiang , Yu Linhong , Zhao Dan , Guan Xiaoxuan , Wang Yingdi , Wang Yani , Li Yisong , Hu Jianqiang , Liu Jie 

TITLE=Association of coagulase-negative staphylococci with orthopedic infections detected by in-house multiplex real-time PCR

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1400096

DOI=10.3389/fmicb.2024.1400096

ISSN=1664-302X

ABSTRACT=<sec id="sec1001"><title>Introduction</title><p>Clinical significance of coagulase-negative staphylococci (CoNS) has been gradually acknowledged in both healthcare and clinical research, but approaches for their precise discrimination at the species level remain scarce. The current study aimed to evaluate the association of CoNS with orthopedic infections, where accurate and prompt identification of etiology is crucial for appropriate diagnosis and treatment decision-making.</p></sec><sec id="sec2001"><title>Methods</title><p>A 16S rRNA-based quantitative PCR (qPCR) assay was developed for the detection of <italic>Staphylococcus</italic> genus and two panels of 3-plex qPCR assays for further differentiation of six CoNS species with remarkable clinical significance, including <italic>S. epidermidis</italic>, <italic>S. haemolyticus</italic>, <italic>S. simulans</italic>, <italic>S. hominis</italic>, <italic>S. capitis</italic>, and <italic>S. caprae</italic>. All the assays exhibited excellent analytical performance. ΔCq (quantification cycle) between 16S rRNA and CoNS species-specific targets was established to determine the primary CoNS. These methods were applied to detect CoNS in wound samples from orthopedic patients with and without infection.</p></sec><sec id="sec3001"><title>Results and discussion</title><p>Overall, CoNS were detected in 17.8% (21/118) of patients with clinically suspected infection and in 9.8% (12/123) of patients without any infection symptom (<italic>p</italic> &lt; 0.05). Moreover, the association with infection was found to be bacterial quantity dependent. <italic>S. epidermidis</italic> was identified as the predominant species, followed by <italic>S. simulans</italic>, <italic>S. haemolyticus</italic>, and <italic>S. hominis</italic>. Male sex, open injury, trauma, and lower extremity were determined as risk factors for CoNS infections. CoNS-positive patients had significantly longer hospitalization duration (20 days (15, 33) versus 13 days (7, 22) for <italic>Staphylococcus</italic>-negative patients, <italic>p</italic> = 0.003), which could be a considerable burden for healthcare and individual patients. Considering the complex characteristics and devastating consequences of orthopedic infections, further expanding the detection scope for CoNS may be pursued to better understand the etiology of orthopedic infections and to improve therapeutic strategies.</p></sec>