Miari Victoria F, Blakiston Matthew R, Solanki Priya, Gundogdu Ozan, Stabler Richard A
Department of Infection Biology, London School of Hygiene & Tropical Medicine Faculty of Infectious and Tropical Diseases, London, UK
Department of Infection Biology, London School of Hygiene & Tropical Medicine Faculty of Infectious and Tropical Diseases, London, UK.
Sex Transm Infect. 2025 Mar 24;101(2):88-93. doi: 10.1136/sextrans-2024-056297.
, the aetiological agent of gonorrhoea, is an increasing global health priority due to high levels of antimicrobial resistance (AMR). It is estimated that up to 42% of patients are infected at multiple anatomical sites simultaneously. Previous studies identified that 7%-40% of those with multisite infection have different strains infecting different sites, with potentially different antimicrobial susceptibility profiles. This study aims to estimate the proportion of patients with multisite infection through differential antimicrobial susceptibility testing (AST) profiles and sequence-based molecular methods.
This was a cross-sectional study of multisite gonococcal isolates provided by three National Health Service laboratories. Minimum inhibitory concentrations (MICs) for cefixime, ceftriaxone, azithromycin, ciprofloxacin, tetracycline and spectinomycin were determined. Possible multistrain infections were defined as isolates with a significant difference in MIC to at least one antimicrobial. Whole genome sequencing (WGS) was performed to determine multistrain infection through multiantigen sequence typing (-MAST), sequence typing for antimicrobial resistance (-STAR), multilocus sequencing typing (MLST) and single nucleotide polymorphism (SNP) phylogeny, and to compare AST profiles with identified AMR genes.
Ninety-one isolates were collected from 41 patients with multisite infections. Of these 41 patients, 6 (14.6%) had isolates with discordant MICs. WGS-based typing confirmed that four out of six patients were infected with different gonococcal strains. The relatedness of isolates with the same MLST across multiple patients was differentiated using SNP-based analysis, and this included the identification of a potential transmission event. WGS-based AMR prediction for all antimicrobials tested correlated well with the phenotypic data.
This study demonstrates that potentially a significant proportion of patients with multisite infections are infected with multiple gonococcal strains, with differing AST profiles, at different anatomical sites. This has implications for patient sampling, susceptibility testing protocols, AMR surveillance and potentially appropriate antibiotic therapy.
淋病奈瑟菌作为淋病的病原体，由于高水平的抗菌药物耐药性（AMR），日益成为全球卫生领域的重点关注对象。据估计，高达42%的患者同时在多个解剖部位受到感染。既往研究表明，7%-40%的多部位感染患者不同部位感染的菌株不同，其抗菌药物敏感性谱可能也不同。本研究旨在通过差异抗菌药物敏感性试验（AST）谱和基于序列的分子方法，估算多部位感染患者的比例。
这是一项对三个国民医疗服务体系实验室提供的多部位淋病奈瑟菌分离株进行的横断面研究。测定了头孢克肟、头孢曲松、阿奇霉素、环丙沙星、四环素和大观霉素的最低抑菌浓度（MIC）。可能的多菌株感染定义为对至少一种抗菌药物的MIC有显著差异的分离株。进行全基因组测序（WGS），通过多位点抗原序列分型（-MAST）、抗菌药物耐药性序列分型（-STAR）、多位点测序分型（MLST）和单核苷酸多态性（SNP）系统发育分析来确定多菌株感染，并将AST谱与已鉴定的AMR基因进行比较。
从41例多部位感染患者中收集了91株分离株。在这41例患者中，6例（14.6%）的分离株MIC不一致。基于WGS的分型证实，6例患者中有4例感染了不同的淋病奈瑟菌菌株。使用基于SNP的分析区分了多个患者中具有相同MLST的分离株之间的相关性，这包括识别一次潜在的传播事件。基于WGS对所有测试抗菌药物的AMR预测与表型数据相关性良好。
本研究表明，多部位感染患者中可能有相当比例在不同解剖部位感染了多种淋病奈瑟菌菌株，其AST谱不同。这对患者采样、敏感性试验方案、AMR监测以及潜在的适当抗生素治疗具有重要意义。
