Exacerbations of chronic obstructive pulmonary disease (ECOPD) remain a major cause of mortality and morbidity of COPD patients. Despite advances in the understanding of their pathophysiology, their assessment relies primarily on clinical presentation which can be variable and difficult to predict. A large number of biomarkers have already been assessed in this context and some appear to be promising.

Methods: An online search for articles published until December 2010 was conducted using 3 terms for ECOPD, 5 terms for biomarkers and 5 terms regarding the sampling method. Biomarkers were evaluated for their potential role in the establishment and/or confirmation of the diagnosis of ECOPD, the evaluation of etiology and severity, the prediction of prognosis and the guidance of treatment decisions.

Results: Several systemic biomarkers have been measured in the context of ECOPD and most of them have been found to increase at ECOPD onset and to subside during the course of exacerbations. Correlations have been reported among these biomarkers but direct associations with clinical variables have been more difficult to establish. Although there are several limitations yet to be addressed, some of the biomarkers, and most notably C-reactive protein for the identification of a COPD exacerbation and procalcitonin for antibiotic guidance, may provide clinically relevant information.

Conclusions: So far no single biomarker has been able to gain wide acceptance, but some provide clinically useful information. The evaluation of such biomarkers in large decision-making studies is expected to become an area of intense investigation in the near future.