Markers Of Treatment Failure In Hospitalized Community-Acquired Pneumonia

Abstract

Background: Lack of response to treatment in community-acquired pneumonia (CAP) worsens outcome. We evaluated the systemic cytokine profile -TNFα, IL1, IL6, IL8 and IL10- C-reactive protein (CRP) and procalcitonin (PCT) in patients with CAP who had treatment failure.

Methods: A prospective study was performed in hospitalized patients with CAP. Cytokines, PCT and CRP measurements were obtained on day 1 and after 72 hours of treatment. Treatment failure was the endpoint evaluated, with separation of those with early (≤72hours) or late failure.

Results: 453 patients were included: 84 (18 %) had treatment failure, of which 38(8 %) were early failure. The median levels of IL-6, PCT and CRP on days 1 and 3 and the median level of IL-8 on day 1 were significantly higher in patients with any treatment failure. Logistic regression analysis demonstrated that values above the following cut-off points for IL-6 (≥169 pg/ml), IL-8 (≥14)and CRP (≥21.9 mg/dl), on day 1 had independent predictive value for any treatment failure after adjustment for initial severity; relative risks (OR) found were 1.9, 2.2 and 2.6 respectively. Increased levels for CRP and PCT at day 1 were also independent predictors for early failure. Increased levels for IL-6 and CRP were the best predictors of late failure.

Conclusions: Serum levels of CRP, IL-6 and PCT on days 1 and 3 are independently associated with a higher risk of any treatment failure. Low levels of PCT and CRP on day one have a high negative predictive value for early failure