The real life application of a procalcitonin-based algorithm to reduce antibiotic exposure in hospitalized patients with community acquired pneumonia: a proof of concept

Community-acquired pneumonia (CAP) represents a common cause of hospitalization in Internal Medicine wards and a frequent cause of antibiotic prescription. An approach based on procalcitonin (PCT) algorithm, has shown to reduce the antibiotic exposure without affecting outcome, in patients admitted to hospital for pneumonia We conducted a study to evaluate the role of a PCT algorithm in a real-life perspective, to reduce the length of antibiotic treatment (AT) in patients hospitalized with CAP. We performed a prospective case-control study, enrolling patients with CAP admitted to an Internal Medicine ward of Careggi Hospital, between December 2013 and February 2014. We used a validated algorithm of AT guided by PCT in CAP. Discontinuation of AT was strongly indicated when PCT level was normal or reduced by 80% in patients with PCT values higher than 10 pg/mL on admission. PCT was drawn on admission, 24 h, 4^th day and 6^th day from admission. The outcomes evaluated were the length of AT, the length of in hospital stay, mortality and serious adverse clinical events. Forty-six patients were consecutively enrolled. On 20 patients, AT was discontinued according to protocol and on 26 patients the AT was continued on clinical judgement. At the baseline, both groups were similar regarding clinical, laboratory, microbiology characteristics, and CURB-65 score. PCT guidance reduced total antibiotic exposure (5.1±1.5 vs 9.1±5.8 days, P=0.005) without any increase of mortality or serious clinical event. In our study, a PCT algorithm was a useful and safe tool to guide the AT in patients with CAP, reducing the antibiotic exposure.