Biomarkers in the diagnosis of pneumonia in the critically ill: don't shoot the piano player

Excerpt

Sir: The diagnosis of pneumonia in critically ill patients remains an area of much uncertainty. Despite two decades of very intensive efforts and many highly sophisticated study designs and debates, the key issue as to whether quantitative cultures of respiratory samples independently predict the presence of pneumonia and the need for antimicrobial treatment in a patient with suspected pneumonia still could not be resolved consensually [1‐3]. Moreover, the investigation of the relative role of noninvasive and invasive diagnostic tools exerted highly conflicting results [3]. An approach focusing on the impact of diagnostic procedures on clinical outcomes and antimicrobial drug consumption, rather than on operative characteristics of diagnostic tests, was launched by Spanish and French authors, again generating conflicting results [4, 5]. To date, we feel that diagnosing pneumonia in the critically ill to a large extent means to deal with uncertainties, and that algorithms should be open for individual decision making [6]. …