Fatty acid-binding proteins as biomarkers of disease severity and outcome in community-acquired pneumonia

In Western Europe, which is experiencing progressive population ageing, community-acquired pneumonia (CAP) is the leading cause of death due to infection, with approximately 90% of the mortality in adults occurring in those aged >65 years (1). A similar situation exists in the United States of America (2). The increasing frequency of CAP in developed countries, predominantly among the aged, has been paralleled by a growing rate of admissions to intensive care units (ICUs), which has increased significantly over the past 2–3 decades (3). Indeed CAP represents one of the leading causes of admission to ICU, with between 13% and 22% of patients hospitalised with CAP having been reported to require ICU admission (4). Notwithstanding the increasing burden of CAP associated with high-risk, ageing populations, other factors which contribute to this increase in the rate of ICU admissions include improved access to modern health care facilities equipped with sophisticated diagnostic and life-support technologies and staffed by highly-trained critical care physicians and nursing personnel. Another possible contributory factor is the uptake of reliable, predictive clinical scoring systems, specifically the pneumonia severity index (PSI) and the CURB-65 (3-5). Disappointingly, however, overall CAP-related mortality rates remain high, ranging from 5–50% according to geographic region (6,7), with the elderly, not surprisingly, at particularly high risk (8-11).