Procalcitonin
Contents
Procalcitonin is usually produced in
[A] Thyroid
[B] Liver
[C] Bone Marrow
[D] Plasma cells
For Procalcitonin levels measurement in blood, Patients should be cautioned to stop ——— consumption at least 72 hours before collecting a sample.
[A] Calcium Tablets
[B] Biotin Supplimentation
[C] Thyroxin Supplimentation
[D] B12 Supplimentation
Procalcitonin
• Procalcitonin is produced by parafollicular cells (C cells) of the thyroid and by the neuroendocrine cells of the lung and the intestine.
• Procalcitonin is usually produced in the thyroid, during bacterial infections it is released by the neuroendocrine cells of the lung and intestine and as an acute-phase reactant.
Thyroid C cells – pre-procalcitonin – procalcitonin – calcitonin
Procalcitonin
- Regarded as a biomarker specific for bacterial infections
- PCT measurement aids in the diagnosis of sepsis and to guide and monitor antibiotic therapy.
- Physiological conditions- very low serum PCT levels of less than 0.05 ng/mL.
- Synthesis of PCT can be increased up to 100 to 1000 fold due to circulating endotoxins or cytokines such as interleukin (IL)- 6, tumor necrosis factor (TNF)-alpha, and IL-1b, which act on various tissues
Extra-thyroid synthesis of PCT
Extra-thyroid synthesis of PCT occurs in the
- Liver
- Pancreas
- Kidney
- Lung
- Intestine
- Leukocytes
Synthesis of PCT is suppressed within these tissues in the absence of bacterial infection.
Viral infection cause – down-regulation of PCT
Viral infection [interferon (INF)-gamma] – leads to the down-regulation of PCT
