Difference of Clinical Manifestation Between Infection and Colonization of Pseudomonas aeruginosa Among Patients With Community-Acquired Pneumonia.

BACKGROUND

Distinguishing infection and colonization from respiratory samples is challenging. We aimed to determine useful markers for differentiating infection from colonization in community-acquired pneumonia (CAP) patients.

METHODS

We included CAP patients in whom was isolated from sputum but were not initially treated with targeting antibiotics. Patients cured with antibiotics not targeting were defined as colonization cases, and those unresponsive to antibiotics not targeting and cured with antibiotics targeting were defined as infection cases.

RESULTS

Of 299 CAP patients, 203 (68%) were treated with antibiotics not targeting in their initial regimen. After excluding 73 of 203 patients who were not cured with antibiotics targeting in subsequent regimens, 17 and 113 were classified as infection and colonization cases, respectively. Systolic blood pressure in the infection group was significantly lower than that in the colonization group (odds ratio = 0.971, 95% confidence interval: 0.946-0.996); no other significant differences were observed.

CONCLUSIONS

Low systolic blood pressure might be a useful marker for distinguishing isolated that need to be targeted from those that do not need to be targeted. However, interventional research is required to validate our study results.