The potential role of 13-valent pneumococcal conjugate vaccine in preventing respiratory complications in bacteraemic pneumococcal community-acquired pneumonia.

BACKGROUND

Pneumococcal 13-valent vaccine (PCV-13) has a potential role in preventing bacteraemic pneumococcal pneumonia and its complications, but little is known about its ability to specifically prevent respiratory complications. Our aim were to analyse the pneumococcal serotypes associated with the development of respiratory complications and the potential role of PCV-13 in preventing respiratory complications in bacteraemic pneumococcal pneumonia.

METHODS

We analysed demographic characteristics, comorbidities, antibiotic resistances and the outcomes of a cohort of 65 vaccine-naïve bacteraemic pneumococcal pneumonias, stratified by the pneumococcal serotypes included in PCV13 vs. those not included. Complications were clustered as follows: respiratory complications (hypoxemic respiratory failure; mechanical ventilation), systemic complications (septic shock; multiorgan failure), suppurative complications (empyema; pleural effusion; lung abscess).

RESULTS

From a population of 65 CAP-SP, 47.7% of the isolates belonged to PCV-13 serotypes group. No differences in comorbidities or clinical manifestations were found between groups. With regard to biochemical parameters, we found more profound hypoxemia levels in PCV-13 serotypes group comparing to non-vaccine group [PaO2/FiO2 209 (63) vs. 268 (57); p=0.007]. Global complications were identified in 69.2% (45 patients), and the most frequent were respiratory complications, found in 47.7%. Respiratory complications were detected more frequently in PCV-13 groups compared to non-vaccine groups (61.3% vs. 35.3%; p=0.036). Overall 30-day mortality was 30.8%. Mortality was similar between both groups (25.8% vs. 35.3%; p=0.408).

CONCLUSIONS

Pneumococcal 13-valent conjugate vaccine includes the serotypes which cause more respiratory complications in our series; these serotypes were not associated with higher mortality in our series. PCV-13 may have a potential role in preventing respiratory complications due to bacteraemic pneumonoccal pneumonia.