Towards evidence based emergency medicine: best BETs from the Manchester Royal Infirmary. BET 1: use of a procalcitonin algorithm to guide antimicrobial therapy in COPD exacerbations can reduce antibiotic consumption with no increase in rates of treatment failure or mortality.

A shortcut review was carried out to establish whether a procalcitonin-guided algorithm could safely reduce antibiotic consumption for patients with an exacerbation of chronic obstructive pulmonary disease attending the emergency department. Four randomised controlled trials were found directly relevant to the three-part question, combined within a later systematic review and meta-analysis. A further prospective cohort study was also found relevant to the three-part question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that a procalcitonin algorithm appears to be a useful strategy to guide initiation and duration of antibiotics and can reduce consumption without conferring additional risk. However, no cost effectiveness data are available as yet and further validation studies are required prior to widespread recommendation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.