The aim of this study was to assess the risk factors and clinical and microbiological characteristics of community-acquired pneumonia (CAP) in adult patients in Mexico. Streptococcus pneumoniae classified as the causative agent of CAP in adult patients and patients with invasive S. pneumoniae isolates presented to three tertiary teaching hospitals during the 15-year study period were selected. Serotyping and susceptibility testing were performed for all included isolates. Clinical and demographic data were recorded. A total of 96 patients infected with S. pneumoniae (71 with CAP, 25 with invasive disease) were included. The CAP group involved more males (74.6%) than the invasive disease group (p = 0.03). Head trauma was more common in the CAP group (21.1%) than in the invasive disease group (4.0%; p = 0.03). The most prevalent serotype was 19A, followed by serotypes 3 and 23F. After the introduction of the heptavalent conjugated pneumococcal vaccine (PCV7), the prevalence of included serotypes declined significantly; no such change was found after the introduction of the PCV13 vaccine, including in the prevalence of serotype 19A. Susceptibility to all antimicrobials tested except vancomycin declined over the study period. In conclusion, head trauma was the most common comorbidity in the CAP group. The most prevalent serotype was 19A. Decreased susceptibility to most antimicrobials tested was observed.

这项研究的目的是评估墨西哥成年患者社区获得性肺炎（CAP）的危险因素以及临床和微生物学特征。选择在15年研究期间向三所三级教学医院呈报的成年患者和侵袭性肺炎链球菌分离株患者被分类为CAP的病原体的肺炎链球菌。对所有包括在内的分离株进行血清分型和药敏试验。记录临床和人口统计学数据。纳入总共96例感染肺炎链球菌的患者（71例CAP，25例侵袭性疾病）。与侵入性疾病组相比，CAP组涉及的男性更多（74.6％）（p = 0.03）。CAP组（21.1％）比浸润性疾病组（4.0％；p  = 0.03）更常见于头部创伤。最流行的血清型是19A，其次是血清型3和23F。引入七价结合型肺炎球菌疫苗（PCV7）后，所含血清型的流行率显着下降。引入PCV13疫苗后（包括血清型19A的流行）未发现此类变化。在研究期间，除万古霉素外，所有接受测试的抗生素的敏感性均下降。总之，在CAP组中，头部外伤是最常见的合并症。最普遍的血清型是19A。观察到对大多数测试抗生素的敏感性降低。