Procalcitonin (PCT): How Is the Infection Test Interpreted?

Overview

Procalcitonin, or PCT, is a blood marker that may rise during some systemic bacterial infections. In seriously ill patients it can support infection assessment and monitoring of treatment.

How is it assessed?

A low PCT cannot rule out all infections; a high result does not identify the bacteria or independently determine whether antibiotics are needed. Recent surgery and major tissue injury can affect levels.

Practical next steps

Share when fever began, medicines already taken, other test results and underlying illnesses. Treatment decisions depend on examination and the full clinical picture.

When is urgent help needed?

Confusion, low blood pressure, breathing difficulty or rapidly worsening illness may signal sepsis and require emergency evaluation.

Frequently asked questions

Is this information enough for a diagnosis?

No. Symptoms, examination, personal history and additional tests when needed must be considered together.

This article provides general health information and is not a substitute for individual assessment, diagnosis or treatment by a qualified professional.

Source: https://medlineplus.gov/lab-tests/procalcitonin-test/