Area Biochemistry and Molecular Biology, OneHealth-UR Research Group, University of La Rioja, Logroño, Spain.
Service of Microbiology, University Hospital Miguel Servet, Spain; IIS Aragón, Spain.
Microb Pathog. 2024 Dec;197:107016. doi: 10.1016/j.micpath.2024.107016. Epub 2024 Oct 15.
Staphylococcus aureus is one of the most prevalent pathogens in cystic fibrosis (CF), being of special relevance those methicillin-resistant (MRSA). The livestock-associated (LA)-MRSA lineage CC398 is an emerging problem, specially related to pig-farming (PF) environments. The objective was to characterize the S. aureus isolates recovered from CF-patients in a Spanish hospital located in a region with high-PF activity.
Forty-two isolates were obtained (January-October/2022) and characterised (one/patient). The antimicrobial resistance phenotype/genotype was evaluated by Microscan/PCR. The presence of virulence and Immune Evasion Cluster (IEC) genes as well as the agr type was determined by PCR. MLST and spa-typing were studied by PCR-sequencing.
Nine of the 42 isolates were MRSA (21.4 %), and 8 of them multidrug resistant (MDR). Among MRSA, 6 spa-types were detected, assigned to CC1, CC5, CC8, CC30, and CC398. Four MRSA isolates belonged to the lineage CC398-t011-IEC negative (animal adapted-clade, LA-MRSA). The remaining 33 isolates were methicillin-susceptible (MSSA), of 26 spa-types and associated with 11 CCs (predominant: CC5, CC30, and CC398). Seven MSSA isolates were of the lineage CC398 (spa-types t034, t108, t571, t20352); four of them were IEC-positive and erm(T)-positive (t571, and t20352, human-adapted CC398 clade), being IEC-negative the remaining three. The tst and eta/etb genes were identified in 12 and 2 isolates, respectively (none CC398). Small-colony-variants were demonstrated in 9 isolates (two CC398, both MDR).
The lineage CC398 was very frequent among CF-patients (26.2 %), both among MSSA and MRSA. The emergence of LA-MRSA-CC398 in CF-patients requires monitorization, especially in hospitals of high-PF-regions.
金黄色葡萄球菌是囊性纤维化（CF）中最常见的病原体之一，其中耐甲氧西林金黄色葡萄球菌（MRSA）尤为重要。与牲畜相关（LA）-MRSA 谱系 CC398 是一个新出现的问题，特别是与养猪（PF）环境有关。本研究的目的是描述从西班牙一家医院的 CF 患者中分离到的金黄色葡萄球菌，该医院位于一个 PF 活动频繁的地区。
2022 年 1 月至 10 月期间，共获得 42 株分离株（每个患者一株），并进行了特征分析。通过 Microscan/PCR 评估了抗菌药物耐药表型/基因型。通过 PCR 检测了毒力和免疫逃避簇（IEC）基因以及 agr 型的存在。通过 PCR 测序研究了 MLST 和 spa 型。
42 株分离株中，9 株为 MRSA（21.4%），其中 8 株为多药耐药（MDR）。在 MRSA 中，检测到 6 种 spa 型，分别归属于 CC1、CC5、CC8、CC30 和 CC398。4 株 MRSA 分离株属于 CC398-t011-IEC 阴性（动物适应谱系，LA-MRSA）。其余 33 株为耐甲氧西林金黄色葡萄球菌（MSSA），有 26 种 spa 型，与 11 种 CC 相关（主要为 CC5、CC30 和 CC398）。7 株 MSSA 分离株属于 CC398（spa 型 t034、t108、t571、t20352）；其中 4 株为 IEC 阳性和 erm(T)阳性（t571 和 t20352，人适应 CC398 谱系），其余 3 株为 IEC 阴性。12 株和 2 株分别鉴定出 tst 和 eta/etb 基因（均非 CC398）。9 株为小菌落变异株（2 株 CC398，均为 MDR）。
CF 患者中 CC398 谱系非常常见，包括 MSSA 和 MRSA。CF 患者中 LA-MRSA-CC398 的出现需要监测，特别是在 PF 高发地区的医院。
