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Bacterial co-infection with H1N1 infection in patients admitted with community acquired pneumonia

Catia Cillóniz1, Santiago Ewig, Rosario Menéndez

  • 1Department of Pneumology, Institut del Tórax, Hospital Clinic, IDIBAPS, University of Barcelona, Villarroel 170, Barcelona 08036, Spain.

The Journal of Infection
|May 1, 2012
PubMed
Abstract

Insights

Bacterial co-infection was common in patients with influenza A H1N1 pneumonia. While chronic obstructive pulmonary disease (COPD) and high platelets predicted co-infection, it did not increase mortality.

Area of Science:

  • Infectious Diseases
  • Pulmonology
  • Critical Care Medicine

Background:

  • Bacterial co-infection significantly contributes to severe illness and death during influenza pandemics.
  • Investigating influenza A H1N1 pneumonia with bacterial co-infection is crucial for understanding patient outcomes.

Purpose of the Study:

  • To determine the incidence, risk factors, and outcomes of bacterial co-infection in hospitalized patients with influenza A H1N1 pneumonia.
  • To compare outcomes between patients with and without bacterial co-infection.

Main Methods:

  • Prospective observational study of hospitalized patients diagnosed with influenza A H1N1 virus and community-acquired pneumonia (CAP).
  • Comparison of clinical characteristics and outcomes between patients with and without bacterial co-infection.

Main Results:

  • Bacterial co-infection occurred in 33% of 128 patients with influenza A H1N1 pneumonia; Streptococcus pneumoniae was the most common pathogen.
  • Chronic obstructive pulmonary disease (COPD) and elevated platelet counts were predictors of bacterial co-infection.
  • Hospital mortality was 9%, with age, septic shock, and mechanical ventilation as mortality predictors. Bacterial co-infection did not significantly impact hospital mortality (7% vs. 11%).

Conclusions:

  • Bacterial co-infection is frequent in influenza A H1N1 pneumonia, with COPD and increased platelet count as key predictors.
  • Despite presenting with higher severity scores, bacterial co-infection did not lead to increased mortality in these patients.

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