Procalcitonin (PCT) is a hormonally inactive glycoprotein containing 116 amino acids. Produced by thyroid-C cells under physiological conditions, it is barely detectable in serum or cerebrospinal fluid of healthy people.
Its sensitivity and specificity are much higher than the traditional detection of C-reactive protein and peripheral blood white blood cell count, so PCT testing reagent has important clinical diagnosis and differential diagnosis value.
Clinical application of PCT testing reagents：
1. Department of Hematology and Oncology
Severe infections are a fatal complication in immunosuppressed and neutropenic patients undergoing chemotherapy or bone marrow transplantation. Fever is usually caused by bacterial, viral, or fungal infections, and may also be a course of treatment. Fever due to tumor cell lysis is also common, and the source of the fever in most cases remains unclear.
At this time, the content of the PCT diagnostic kit, especially the continuous increase, will help to make a clear diagnosis of systemic infections and septic infections caused by bacteria and fungi in such patients. And can make differential diagnosis of viral infection.
Patients with bone marrow transplantation or hematopoietic stem cell transplantation all have defects in humoral and cellular immune functions, which may mask serious systemic infections caused by bacteria, fungi, viruses and protozoa and cause clinical artifacts.
Elevated PCT concentration has a high diagnostic rate for bacterial, fungal and protozoal systemic infections. If the plasma PCT concentration of patients with septic shock after allogeneic transplantation is extremely elevated, it often indicates a poor prognosis.
2. Department of Anesthesiology
Postoperative sepsis infection and multiple organ failure remain the most common causes of death currently in intensive care units. PCT can be moderately elevated within 12-24 hours after compound trauma, and the PCT testing reagent for severe lung or chest trauma can reach 5.0ng/ml. In the absence of bacterial infection complications, PCT usually returns to normal more quickly.
3. Organ transplantation
Successful organ transplantation is often challenged by serious infectious complications. In the past, for 31℅ patients, various infections that were prone to occur within the first year after organ transplantation and were easily masked by acute and chronic rejection, it was often impossible to make a reliable diagnosis at an early stage.
PCT diagnostic kits can make decisions on the need for early introduction of anti-infective therapy in such organ transplant patients, thereby improving patient survival, shortening hospital stays, and reducing medical costs.
The release of PCT is not caused by the stimulation of acute or chronic organ rejection, so the persistent high concentration of PCT after surgery can be considered as the existence of bacterial infection, especially the concentration of PCT testing reagent exceeds 10ng/ml, 98℅ May be due to infection rather than organ rejection. Therefore, the detection of PCT can make a clear distinction between postoperative infection and organ rejection.
4. Internal Medicine and Neurology
Intensive care in internal medicine and neurology is often troubled by the differential diagnosis of infection and whether it is related to infection. The evaluation of the severity of inflammation and the effectiveness of treatment outcomes is a necessary prerequisite for an effective treatment plan.
Because the PCT testing reagent has a selective response to systemic bacterial, fungal and protozoal infections, but has no response or only mild transient response to aseptic inflammation and viral infection, it can be more convenient for such medical and neurological diseases. Differential diagnosis of common diseases and syndromes in internal medicine.
5. Neonatology
The physiologic peak of neonatal PCT can reach 21ng/ml at 24-30 hours after birth, but the average is only 2ng/ml. The normal reference value of PCT testing reagents in newborns on the third day after birth can be the same as that of adults.
Therefore, PCT is a highly specific indicator of neonatal sepsis, which has an earlier and more specific diagnostic value than traditional methods, and its sensitivity and specificity can reach 100℅.
6. Surgery
The concentration of PCT testing reagents is not affected by pre-existing diseases such as cancer, allergy or autoimmune diseases, so it has unique diagnostic advantages, even better than those with invasive, high-risk and high-cost diagnostic methods.
PCT is closely related to the occurrence and process of severe bacterial and sepsis infection, and can accurately reflect whether the source of infection has been eradicated. Daily monitoring of PCT concentration can also make a reliable evaluation of treatment results.
In patients with cardiac surgery or cardiac surgery who have used a heart-lung machine, even if there is leukocytosis, neutropenia, and eosinophilia after surgery, if there is no concurrent bacterial infection, the concentration of PCT testing reagent is usually not increased or only slightly Elevated, and help in the identification of sepsis.
