Related Experiment Videos
Comparative study of Legionella pneumophila and other nosocomial-acquired pneumonias
1Servei de Pneumologia, Hospital Germans Trias i Pujol, Badalona, Barcelona, Spain.
Abstract:
We studied, in a prospective way, the characteristics of definitively diagnosed nosocomially acquired pneumonias in our hospital over 36 months. Out of 55 cases, 27 were due to Legionella pneumophila and 28 to other, non-Legionella bacteria. The cases of legionellosis concentrated in July, August, and December. The only risk factors that showed significant differences (p less than 0.05) were general anesthesia and surgery and immunosuppressive disease, which were more frequent in the non-Legionella group, as were chronic liver disease and lowering of consciousness level. The absence of severe underlying disease, chronic or not, was uncommon in both groups, but more frequent in the Legionella group. We observed no differences in the clinical features of the two groups. Mean values of gamma-glutamyltranspeptidase and total bilirubin were higher (p less than 0.05) in the non-Legionella group. The only x-ray data that showed significant difference were pleural effusion, more frequent in the non-Legionella group (p less than 0.02). The mortality rate of legionellosis was 14.6 percent compared to 35.7 percent for the non-Legionella group (p less than 0.05). We conclude that a sure differential diagnosis based on clinical, roentgenographic and analytical features of both groups is not possible. The relatively low mortality rate of the Legionella group, when compared to other series of nosocomial legionellosis, could be due to the standard use of erythromycin in the therapeutic approach to nosocomial-acquired pneumonia in our hospital.
Insights
This study compared hospital-acquired pneumonias, finding Legionella pneumophila cases had lower mortality than other bacterial types. Clinical features and X-rays showed no clear differences, making diagnosis challenging.
Area of Science:
- Infectious Diseases
- Pulmonology
- Hospital Epidemiology
Background:
- Nosocomial pneumonia presents diagnostic challenges.
- Legionella pneumophila is a significant cause of hospital-acquired infections.
- Differentiating Legionella from other bacterial pneumonias is crucial for treatment and outcomes.
Purpose of the Study:
- To prospectively analyze characteristics of nosocomial pneumonias.
- To compare Legionella pneumophila pneumonias with those caused by other bacteria.
- To identify risk factors, clinical features, and outcomes for differential diagnosis.
Main Methods:
- Prospective study of 55 definitively diagnosed nosocomial pneumonia cases over 36 months.
- Categorization into Legionella pneumophila (27 cases) and non-Legionella bacterial (28 cases) groups.
- Analysis of risk factors, clinical presentation, laboratory values, radiographic findings, and mortality rates.
Main Results:
- Legionellosis cases peaked in July, August, and December.
- Risk factors like general anesthesia, surgery, and immunosuppression were more common in the non-Legionella group.
- Pleural effusion on X-ray was more frequent in the non-Legionella group; mortality was significantly lower for Legionella (14.6%) vs. non-Legionella (35.7%).
Conclusions:
- Differential diagnosis between Legionella and non-Legionella nosocomial pneumonia based on clinical, radiographic, or analytical data is not reliably possible.
- The lower mortality in the Legionella group may be linked to early erythromycin use.
- Further research into diagnostic markers and treatment strategies for nosocomial pneumonia is warranted.