PCT Concentration

PCT Interpretations

Risk or Options for Further Action

PCT ≤ 0.5 ng/ml

Low risk for progression to severe systemic infection (severe sepsis/septic shock). Local bacterial infection is possible.

CAUTION: PCT levels below 0.5 ng/ml do not exclude an infection, because localized infections may be associated with such low levels.

If PCT is measured very early after a bacterial challenge (usually <6 hours), these values may still be low. In this case, PCT should be re-assessed 6-24 hours later.

PCT > 0.5 and ≤ 2 ng/ml

Moderate risk for progression to severe systemic infection (severe sepsis/septic shock), but other conditions are known to elevate PCT as well

The patient should be closely monitored both clinically and by re-assessing PCT within 6-24 hours.

PCT > 2 ng/ml and < 10 ng/ml

High risk for progression to severe systemic infection (severe sepsis/septic shock) unless other causes are known

Systemic infection (sepsis) is likely, unless other causes are known.

PCT ≥ 10 ng/ml

High likelihood of severe sepsis or septic shock

Important systemic inflammatory response, almost exclusively due to severe bacterial sepsis or septic shock.