title: Procalcitonin-guided antibiotic treatment of respiratory tract  infections in a primary care setting: are we there yet?
abstract: Clinical signs of infection do not allow for correct identification of bacterial and viral aetiology in acute respiratory infections. A valid tool  to assist the clinician in identifying patients who will benefit from antibiotic therapy, as well as patients with a potentially serious infection,  could greatly improve patient care and limit excessive antibiotic prescriptions. Procalcitonin is a new marker of suspected bacterial  infection that has shown promise in guiding antibiotic therapy in acute respiratory tract infections in hospitals without compromising  patient safety. Procalcitonin concentrations in primary care are low and can be used primarily to rule out serious infection. However,  procalcitonin measurement should not be used as the sole basis for clinical decisions; clinical skills are prerequisites for the correct use of  this new tool in practice. At present there is no point-of-care test for procalcitonin with acceptable precision, severely hampering its  application in primary care. This article reviews the physiology of procalcitonin, describes the assays available for its measurement,  evaluates the present evidence from primary care on its use to identify correctly patients who are likely to benefit from antibiotic  treatment and to rule out serious infections, and comments on further research to determine a future role for procalcitonin in primary  care.
authors.affiliation: Research Unit for General Practice, University of Copenhagen, Denmark. runeaa@sund.ku.dk
authors.forename: Rune
authors.initials: R
authors.lastname: Aabenhus
authors.forename: Jens-Ulrik Stæhr
authors.initials: JU
authors.lastname: Jensen
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood*; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide; D006801:Humans; D007118:Immunoassay / Q000379:methods / Q000592:standards; D011320:Primary Health Care; D011498:Protein Precursors; D012141:Respiratory Tract Infections / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology*; D012680:Sensitivity and Specificity
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide