Procalcitonin testing is used to differentiate viral from bacterial infections.

Procalcitonin testing is used to differentiate viral from bacterial infections.

• A. True
• B. False
• C. Only for children under 2 years
• D. Not used clinically

Answer: (A)

Procalcitonin rises chiefly in bacterial infections, while viral infections typically do not cause a large increase. The viral immune response, especially interferons, tends to suppress procalcitonin production, so levels stay relatively low during viral illnesses. Because of this pattern, procalcitonin testing helps clinicians distinguish bacterial from viral etiologies and guides antibiotic decisions, aiming to avoid unnecessary antibiotics when the infection is likely viral. In practice, higher procalcitonin levels support a bacterial infection and the need for antibiotics, whereas very low levels suggest a non-bacterial process, though there are exceptions (such as certain severe viral infections, early bacterial infections, postoperative or inflammatory states). Therefore, the statement is true.

Procalcitonin rises chiefly in bacterial infections, while viral infections typically do not cause a large increase. The viral immune response, especially interferons, tends to suppress procalcitonin production, so levels stay relatively low during viral illnesses. Because of this pattern, procalcitonin testing helps clinicians distinguish bacterial from viral etiologies and guides antibiotic decisions, aiming to avoid unnecessary antibiotics when the infection is likely viral. In practice, higher procalcitonin levels support a bacterial infection and the need for antibiotics, whereas very low levels suggest a non-bacterial process, though there are exceptions (such as certain severe viral infections, early bacterial infections, postoperative or inflammatory states). Therefore, the statement is true.