Government and Regulations
Mass Transit for Viruses
Researchers at the National Heart, Lung, and Blood Institute have found a never-before-seen means of viral replication.
Limitations of the use of PCT as a clinical biomarker include its inability to be used in immunocompromised patients. In addition, PCT levels are increased in severe, noninfectious inflammatory conditions, such as inhalation injury, pulmonary aspiration, severe burns, pancreatitis, heat stroke, mesenteric infarction, trauma, surgery, and pneumonitis.12 The presence of low-grade inflammation from a bacterial infection can lead to slightly elevated PCT levels that are difficult to quantify due to the low sensitivity of current PCT assays.13
The level of PCT up-regulation may depend on the infecting pathogen. One study showed that PCT was highly elevated in patients with pneumococcal community-acquired pneumonia (CAP), and another study demonstrated that PCT levels did not increase in CAP due to atypical organisms.14,15 Thus, atypical antimicrobial coverage should be continued per current guidelines in patients in whom there is high suspicion of atypical organism-involvement in CAP.
Related: The Importance of an Antimicrobial Stewardship Program
Conclusion
Many studies have analyzed the use of PCT as a biomarker for infectious disease diagnosis, monitoring, and treatment. Current evidence supports its use in RTIs and sepsis, although it may be useful in other conditions as well, such as bacteremia and postoperative infections.2 Due to its limitations and controversy, PCT should not be used as a sole marker but as an adjunct to a patient’s clinical presentation, overall clinical picture, and other biomarkers.
Additional Note
An earlier version of this article appeared in the Pharmacy Related Newsletter: The Capsule, of the William S. Middleton Memorial Veterans Hospital.
Author disclosures
The authors report no actual or potential conflicts of interest with regard to this article.
Disclaimer
The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the U.S. Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review the complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.