A Hospital-based Study on the Local Epidemiology of Pneumonia Including the Contribution of Legionella Pneumonia.

BACKGROUND

In real-life practice, only 20% of hospitalised pneumonia cases have an identified etiology. The usage of urine antigen test (LUAT) in developed nations revolutionised case detection rates. Accordingly, our objectives were to study the microbiological etiology for hospitalised pneumonia patients and the diagnosis of pneumonia.

METHODS

A prospective, observational single-centre study was conducted where all 504 cases that were consecutively admitted for pneumonia were enrolled. Blood and sputum samples obtained were used to identify pathogens using standard microbiological culture methods. The urine samples collected were tested using the Immunocatch immunochromatographic (ICT) urine antigen test.

RESULTS

A microbiological diagnosis was only achieved in 104 cases (20.6%) and a Gram-negative infection predominance was observed. Culture-positive cases required longer hospitalisation (8.46 days versus 5.53 days; < 0.001) and the higher usage of antipseudomonal antibiotics (23.1% versus 8.3%; < 0.001). Only 3 cases (0.6%) were diagnosed with pneumonia.

CONCLUSION

The local pathogen distribution is diverse compared to other regions. Culture-negative pneumonia is common and significantly differs from culture-positive pneumonia. serotype 1 is not a common cause of pneumonia and LUAT did not help demystify the cause of culture-negative pneumonia.