Relationship between pneumococcal serotypes and antimicrobial resistance: A systematic review and meta-analysis

Background: The diversity of pneumococcal serotypes poses significant challenges for both vaccination and treatment. Clinical management of pneumococcal infections is further complicated by the fact that individual serotypes exhibit distinct antimicrobial resistance patterns. This study aims to comprehensively estimate the antimicrobial resistance rates of pneumococcal serotypes. Methods: A comprehensive search was conducted in PubMed, Scopus, Web of Science, and ScienceDirect. A random-effect meta-analysis was used to pool the number of isolates resistant to a particular antimicrobial per total number of isolates tested for each pneumococcal serotype. Results: Ninety studies were included in the analysis. The study identified 66 pneumococcal serotypes, with vaccine serotypes such as 19A, 19F, 23F, 6B, 14, 6A, 3, and 9V being the most frequently reported. Non-vaccine serotypes like 15A, 6C, 23A, 23B, 15B, and 35B were also prevalent. Most serotypes were associated with pneumococcal diseases. Serotypes exhibited varying and high resistance to cefuroxime, co-trimoxazole, tetracycline, macrolides, and clindamycin. The highest multidrug resistance was observed in serotypes 23F (63.34%, 95% CI [25.77; 94.31]), 15C (61.04%, 95% CI [0.74; 100.00]), 23A (57.28%, 95% CI [27.60; 84.58]), 19F (55.95%, 95% CI [30.26; 80.22]), 19A (54.07%, 95% CI [32.60; 74.90]), 15B (47.10%, 95% CI [9.66; 86.41]), 24F (45.77%, 95% CI [3.79; 91.31]), 15A (44.28%, 95% CI [29.58; 59.26]), and 6B (43.79%, 95% CI [28.48; 59.12]). Conclusions: This study highlights significant antimicrobial resistance among both vaccine (19A, 19F, 23F, 14, 6A, and 6B) and non-vaccine types (15A, 6C, 23A, 20, 15C, and 35B). Our findings emphasize the need for effective surveillance and targeted interventions to fight these resistant pneumococcal serotypes.