Clinical and microbiological characteristics of pediatric patients hospitalized for pneumococcal pneumonia before and after the introduction of pneumococcal conjugate vaccines.

Abstract

The clinical and microbiological characteristics of pneumococcal pneumonia in children hospitalized in Lima were analyzed, before and after the introduction of pneumococcal conjugate vaccines (PCV). We reviewed cases that occurred between 2006-2019, in the pre-PCV7 (2006-2008), post-PCV7 (2009-2011) and post-PCV13 (2016-2019) periods. Of 128 patients with positive cultures (92 blood and 36 pleural fluid), most were infants in the pre-PCV7 (77.1%) and post-PCV7 (43.3%) studies, while in the post-PCV13 study they were mostly preschoolers (62%). We found an increase in complicated pneumonia cases from 14.6% to 72% and an increase in serotype 19A (6.3% to 68%). The most frequent sequence type was ST320 (31 isolates). Resistance to penicillin and ceftriaxone was low (6% and 2%, respectively), although higher in empyema (21.4% and 14.3%, respectively). Resistance to azithromycin increased from 27% to 92%. Penicillin remains the antibiotic of choice for the treatment of uncomplicated pneumococcal pneumonia in Lima. Motivation for the study. Although studies on invasive pneumococcal disease have been conducted in Lima, the characteristics of pneumococcal pneumonia before and after the introduction of pneumococcal conjugate vaccines are unknown. Main findings. We found an increase in complicated pneumococcal pneumonia cases, particularly empyema and an increase in serotype 19A. Resistance to penicillin and ceftriaxone was found to be low; however, in cases of empyema, antibiotic resistance was higher. Public health implications. Penicillin or amoxicillin should continue to be prescribed for the empirical management of pneumococcal pneumonia; however, ceftriaxone is recommended for cases with empyema. Continued local monitoring of pneumococcal resistance and serotypes is recommended.