Evaluation of the IDSA/ATS minor criteria for severe community-acquired pneumonia.

Our aim was to evaluate the minor criteria recommended by the 2007 Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS) as predictors of 30-day mortality, the need for invasive mechanical ventilation, and/or the need for vasopressor support as markers of severity in patients hospitalized with community-acquired pneumonia (CAP). Patients admitted to 2 academic teaching hospitals over a 4-year period (January 1, 1999 to December 1, 2002) were identified as having CAP. We used modified minor criteria established by the 2007 IDSA/ATS guidelines. The primary outcome measure was 30-day mortality, and the secondary outcome measures were need for invasive mechanical ventilation and/or need for vasopressor support. About half of the patients in the cohort (n = 352/787 [46%]) had ≥ 1 minor criterion, but only 128 (16.3%) had ≥ 3 minor criteria present at hospital admission. In the multivariable analysis, hypoxemia, multilobar infiltrates, and leukopenia were associated with 30-day mortality (P < 0.05). In addition, hypoxemia and confusion/disorientation were associated with the need for invasive mechanical ventilation and/or vasopressor support (P < 0.05). The presence of ≥ 3 minor criteria was associated with 30-day mortality (odds ratio, 4.82), and the need for invasive mechanical ventilation and/or vasopressor support (odds ratio, 2.59). Our results show that hypoxemia, multilobar infiltrates, and leukopenia were the most predictive minor criteria for 30-day mortality. In contrast, hypoxemia and confusion/disorientation were the 2 individual minor severe criteria that were more likely to require invasive mechanical ventilation and/or vasopressor support. At least 3 2007 IDSA/ATS minor severe criteria were associated with 30-day mortality and need for invasive mechanical ventilation and/or vasopressor support.