Severity assessment of healthcare-associated pneumonia and pneumonia in immunosuppression

The study compares the ability of the PSI (pneumonia severity index), CURB (confusion-uraemia-respiratory rate-blood pressure) scales, and the SCAP (severe community-acquired pneumonia) score to predict 30-day mortality in health-care associated pneumonia (HCAP) patients, and analyses differences in the demographics, aetiology and outcomes of community-acquired pneumonia (CAP), HCAP and pneumonia in immunocompromised patients.Six hundred and twenty-nine consecutive patients admitted to a tertiary care University Hospital were prospectively categorised as having CAP (n=322) or HCAP (n=307) and the HCAP patients were further sub-divided into those who were immunocompromised (n=219) or non-immunocompromised (n=88).The 30-day mortality rate was 9.0% in the CAP group and 24.1% in the HCAP group. In the HCAP group, the PSI and SCAP scores had similar prognostic power (areas under the curve [AUC] of respectively 0.68 and 0.67 respectively), and performed better than the CURB-65 score (AUC≤0.62). Among the non-immunocompromised HCAP patients, the PSI and CURB-65 score were more sensitive than the others at every threshold, whereas SCAP was more specific than both. In the immunocompromised group, the PSI was highly sensitive but poorly specific at all thresholds.Our results suggest that prognostic tools should be designed for the subsets of HCAP patients