Viral and bacterial pathogens identification in children hospitalised for severe pneumonia and parapneumonic empyema

Area of Science:

• Pediatric Infectious Diseases
• Respiratory Medicine
• Microbiology

Background:

• Pneumonia is a common childhood illness caused by bacteria and viruses.
• The role of viral co-infections in the severity of pediatric community-acquired pneumonia (CAP) is not well understood.
• Parapneumonic empyema (PPE) represents a severe form of CAP.

Purpose of the Study:

• To investigate the impact of respiratory pathogens, including viral co-infections, on the severity of pneumonia in hospitalized children.
• To compare the prevalence of viral and bacterial pathogens in children with CAP and those with CAP and PPE.

Main Methods:

• A cohort of 52 hospitalized children with CAP (with or without PPE) was studied between 2007 and 2009.
• Respiratory pathogens were identified in nasopharyngeal aspirates and pleural effusion samples using conventional and molecular assays (real-time multiplex PCR, antigen detection).
• Patients were divided into two groups: CAP (n=24) and CAP + PPE (n=28).

Main Results:

• *Streptococcus pneumoniae* was the primary bacterial agent identified in 76% of cases via molecular tests and BinaxNOW® in pleural fluid.
• Viral co-detection was significantly higher in nasopharyngeal aspirates from patients with CAP + PPE (35%) compared to CAP patients (5%).
• Commonly detected viruses included rhinovirus, parainfluenza viruses, human metapneumovirus, and respiratory syncytial virus.

Conclusions:

• Viral co-detection is more prevalent in children with severe pneumonia, suggesting a potential role in disease exacerbation.
• Molecular diagnostic techniques enhance pathogen detection in pneumonia and confirm findings from rapid antigen tests.
• The predominant *S. pneumoniae* serotypes in PPE cases were not covered by the heptavalent pneumococcal conjugate vaccine.