Streptococcus pneumoniae is an important causal agent of pneumonia, meningitis, sepsis, bacteremia, and otitis media. Penicillin resistance rates in S. pneumoniae have remained stable in Argentina in the last years. In the late ‘90s more isolates with MIC of penicillin ≥2 μg/ml were observed; however, their frequency has decreased in recent years. The phenotypic expression of penicillin resistance is due to a modification in penicillin-binding proteins associated with a mosaic structure in the coding genes. The expansion of successful resistant clones varies among the different regions and is influenced by the use of antibiotics, vaccines, particularly conjugated ones, as well as population density. Parenteral treatment with high doses of penicillin G continues to be effective for the treatment of pneumonia and bacteremia, oral aminopenicillins for otitis media and sinusitis and third generation cephalosporins for meningitis.

肺炎链球菌是肺炎、脑膜炎、败血症、菌血症和中耳炎的重要病原体。过去几年，阿根廷肺炎链球菌的青霉素耐药率一直保持稳定。在 90 年代后期，青霉素 MIC ≥2 的分离株增多 观察到 μg/ml；然而，它们的频率近年来有所下降。青霉素抗性的表型表达是由于与编码基因中的镶嵌结构相关的青霉素结合蛋白的修饰。成功抗性克隆的扩增因地区而异，并受抗生素、疫苗（尤其是结合疫苗）的使用以及人口密度的影响。大剂量青霉素G的肠胃外治疗对肺炎和菌血症的治疗继续有效，口服氨基青霉素治疗中耳炎和鼻窦炎，第三代头孢菌素治疗脑膜炎。