Procalcitonin

Abstract

General considerations:1. Always use high-sensitivity assays for measurement of procalcitonin with a functional assay sensitivity in the range of 0.06 mg/L. 2. Procalcitonin cutoff threshold values depend on the clinical setting and the type of infection.Procalcitonin and initial management of respiratory infections:3. Results should always be interpreted in conjunction with the clinical setting and context; use procalcitonin results to complement, but not replace, your clinical judgment. 4. In low-risk patients (ie, patients with bronchitis, chronic obstructive pulmonary disease exacerbation, or upper respiratory tract infection), initial procalcitonin results can be for decision making regarding the need for antibiotics. 5. In high-risk patients (ie, intensive care unit [ICU]-level patients or patients with severe pneumonia), use procalcitonin for guiding duration of treatment rather than for initiation of therapy. 6. Never wait for initial procalcitonin results in clinically unstable and/or high-risk patients (eg, severe sepsis and need for ICU admission) to start antibiotic therapy. 7. Always check procalcitonin after 6 to 24 hours if initial antibiotics are withheld and patients do not show improvement as clinically expected. CONTINUED CONTINUEDProcalcitonin and duration of antibiotic treatment:8. In low-risk patients, antibiotics can be discontinued if patients show clinical improvement and procalcitonin levels drop to less than 0.1 mg/L or likely even less than 0.25 mg/L. 9. In high-risk patients in the ICU setting, antibiotics can be discontinued if patients show clinical improvement and procalcitonin drops to less than 0.5 mg/L, and/or if levels drop by at least 80% to 90% of peak values. 10. Procalcitonin levels that are not decreasing can be found in patients not responding to antibiotic therapy, and are thus associated with increased risk for adverse patient outcomes. BACKGROUND Definitions