Background
Management of pneumococcal disease is complicated by high rates of antimicrobial resistance (AMR). This study assessed AMR trends for Streptococcus pneumoniae isolates from adults with pneumococcal disease.
Methods
From January 2011 to February 2020, we evaluated 30-day non-duplicate S. pneumoniae isolates from 290 US hospitals (BD Insights Research Database) from adults (≥ 18 years) in inpatient and outpatient settings. Isolates were required to have at least one AMR result for invasive (blood, cerebrospinal fluid/neurologic) or non-invasive (respiratory or ear/nose/throat) pneumococcal disease samples. Determination of AMR was based on facility reports of intermediate or resistant. Descriptive statistics and generalized estimated equations were used to assess variations over time.
Results
Over the study period, 34,039 S. pneumoniae isolates were analyzed (20,749 [61%] from non-invasive sources and 13,290 [39%] from invasive sources). Almost half (46.6%) of the isolates were resistant to ≥ 1 drug and non-invasive isolates had higher rates of AMR than invasive isolates. Total S. pneumoniae isolates had high rates of resistance to macrolides (37.7%), penicillin (22.1%), and tetracyclines (16.1%). Multivariate modeling identified a significant increasing trend in resistance to macrolides (+1.8%/year; P < 0.001). Significant decreasing trends were observed for penicillin (-1.6%/year; P < 0.001), extended-spectrum cephalosporins (ESCs) (-0.35%/year; P < 0.001), and ≥3 drugs (-0.5%/year; P < 0.001).
Conclusions
Despite decreasing trends for penicillin, ESCs, and resistance to ≥3 drugs, AMR rates are persistently high in S. pneumoniae isolates among US adults. Increasing macrolide resistance suggests that efforts to address AMR in S. pneumoniae may require antimicrobial stewardship efforts and higher-valent pneumococcal conjugate vaccines.