[Procalcitonin measurement in adult clinical practice]

The availability of a sensitive, specific and prognostic marker of bacterial infection is a major issue. More than ten years after the first publication assessing the usefulness of serum procalcitonin dosage (PCT), its exact place in the diagnostic process remained to be defined. The purpose of this review is to point out the indications of PCT measurement in clinical practice in the adult population.

PCT is an early, sensitive but above all specific marker of severe bacterial/parasitic infections. After being studied mostly in critically ill patients, the indications of PCT measurement have been extended to medical and emergency medicine practice, generating cut-off points between 0.2 and 0.6 microg/L. The medical area of application of PCT measurement is varied: discrimination between inflammatory disease and infectious complication or between bacterial/parasitic and viral infection, diagnosis of negative result gram staining meningitis or shock, assessment of antibiotic treatment efficiency. Moreover, PCT measurement provides outcome information in that sepsis-related raised PCT levels seem to be closely related to the magnitude of host systemic inflammatory response to microbial invasion. High PCT levels allow the early identification of patients prone to develop severe sepsis or septic shock.

After the first published study reporting the usefulness of PCT as a screening biological tool in emergency medicine, future studies will probably refined the place of PCT in such practice fields: decision about inpatient or outpatient management or antibiotics dispensation. Finally, PCT measurement could help physician in screening which septic patients should benefit from sepsis innovative therapeutics.