Procalcitonin: (PCT)

Procalcitonin (PCT), a protein that consists of 116 amino acids, is the peptide precursor of calcitonin, a hormone that is synthesized by the parafollicular C cells of the thyroid and involved in calcium homeostasis. Procalcitonin arises from endopeptidase-cleaved preprocalcitonin. Procalcitonin (PCT) has a set half-life of 20 to 24 hours which provides clinicians and researchers with a rough timeline of when levels should begin to decrease following physiological control of the systemic infection. When physiologic control is reached, PCT should decrease by approximately 50% over 24 hours. [10] Understand what a PCT ( procalcitonin ) blood test is for, its normal range, and what high or low results might mean. Learn how it helps diagnose infections and guide treatment.