Outcome of cases with S. pneumoniae isolation.

ObjectiveSince the introduction of the pneumococcal conjugate vaccine PCV-10 in 2011 its impact on acute otitis media (AOM) in children under five years of age in Colombia was unknown. We aimed to describe the clinical and sociodemographic characteristics of a prospective cohort of patients between 3 and 59 months old attending a children’s hospital in Cartagena, Colombia.MethodsA prospective cohort study was conducted over a 12-month period from August 5th, 2022 to August 5th, 2023. Diagnosis of AOM was confirmed by an otorhinolaryngologist. Middle ear fluid samples were obtained by swab or tympanocentesis, depending on the presence of spontaneous drainage. Samples with a positive culture for S. pneumoniae were sent to the Colombian National Health Institute for serotyping. We also estimated the prevalence of AOM caused by S. pneumoniae, the serotype distribution and antimicrobial resistance patterns.ResultsA total of 61 patients were enrolled, 58% were male, the median age was 12 months (IQR: 8–24). The most common isolated microorganisms were Pseudomonas aeruginosa (14.8%), methicillin-resistant Staphylococcus aureus (13.1%), and Streptococcus pneumoniae (9,8%). Six cases of S. pneumoniae were identified, median age was 26.5 months (IQR: 8–45), none had any comorbidities, and only one had a history of previous AOM episodes. Five of them were vaccinated. The serotype distribution was 19A (67%), 10F and 35A (17%) each. Within the antimicrobial resistance patterns, serotype 19A was multidrug resistant (resistance to: beta-lactams, macrolides, lincosamides and TMP/SMX).ConclusionS. pneumoniae continues to be a leading cause of AOM in our country. Serotype 19A accounts for 67% of these infections and exhibits a multidrug-resistant pattern similar to that observed in invasive pneumococcal disease. These findings are consistent with international data and provide a baseline for tracking future AOM trends related to S. pneumoniae after the introduction of the PCV-13 vaccine.

研究目的：自2011年肺炎球菌结合疫苗（pneumococcal conjugate vaccine, PCV-10）问世以来，其对哥伦比亚5岁以下儿童急性中耳炎（acute otitis media, AOM）的影响尚未明确。本研究旨在描述哥伦比亚卡塔赫纳一家儿童医院收治的3~59个月龄患儿的前瞻性队列的临床及社会人口学特征。

研究方法：本研究为一项为期12个月的前瞻性队列研究，实施时段为2022年8月5日至2023年8月5日。急性中耳炎的诊断由耳鼻咽喉科医师确认。根据是否存在自发性耳漏，通过拭子采样或鼓膜穿刺术获取中耳积液样本。肺炎链球菌（Streptococcus pneumoniae, S. pneumoniae）培养阳性的样本将被送至哥伦比亚国家卫生研究所进行血清分型。本研究同时估算了肺炎链球菌所致急性中耳炎的患病率、血清型分布及抗菌药物耐药谱。

研究结果：本研究共纳入61例患儿，其中58%为男性，中位年龄为12个月（四分位间距IQR：8~24）。最常见的分离微生物为铜绿假单胞菌（Pseudomonas aeruginosa，14.8%）、耐甲氧西林金黄色葡萄球菌（methicillin-resistant Staphylococcus aureus，13.1%）及肺炎链球菌（9.8%）。共检出6例肺炎链球菌感染病例，患者中位年龄为26.5个月（IQR：8~45），所有患者均无基础疾病，仅1例有既往急性中耳炎发作史。其中5例已完成PCV-10疫苗接种。血清型分布为19A型（67%）、10F型与35A型（各占17%）。在抗菌药物耐药谱方面，19A血清型为多重耐药株，对β-内酰胺类、大环内酯类、林可酰胺类及甲氧苄啶-磺胺甲恶唑（TMP/SMX）均耐药。

研究结论：肺炎链球菌仍是我国急性中耳炎的主要致病菌之一。19A血清型占此类感染的67%，且呈现出与侵袭性肺炎球菌疾病相似的多重耐药模式。本研究结果与国际数据相符，可为追踪PCV-13疫苗引入后哥伦比亚肺炎链球菌相关急性中耳炎的未来流行趋势提供基线数据。