Procalcitonin (PCT) is a calcitonin propeptide substance without hormone activity, a glycoprotein composed of 116 amino acids, with a molecular weight of 13KD; the half-life (T1/2) of PCT is 25~30 hours, and it is stable in vitro, the plasma PCT level of healthy people is extremely low.
1. The sensitivity and specificity of PCT diagnostic reagents are higher than other inflammatory response factors
The sensitivity and specificity of PCT in bacterial infection, especially sepsis, are both as high as 95%, especially the diagnostic specificity of severe sepsis and septic shock is as high as 100%.
PCT appears the earliest in plasma, and the increase in plasma concentration in patients with systemic bacterial infection is earlier than that of CRP and other inflammatory factors. It can be detected within 2 hours with procalcitonin reagent, and it rises sharply within 6 hours. 8-24 hours to maintain a high level.
2. The half-life of PCT in plasma is short, and the diagnostic reagent is an important indicator for the observation of curative effect and prognosis
PCT exists in the plasma for a short time, with a half-life of 22-29 hours. It has good stability in vitro and in vivo and is not easily degraded.
Moreover, the detection of PCT procalcitonin reagent is not affected by clinical medication (except OKT3), and is positively correlated with the severity of infection in the body. Therefore, dynamic observation of changes in plasma PCT concentration can better determine prognosis and curative effect.
3. The increase in the concentration of PCT procalcitonin reagent is not affected by the immunosuppressive state of the body
When the body is in severe bacterial infection or sepsis, even if the patient is in an immunosuppressed state or has no obvious clinical manifestations, the concentration of PCT in the plasma can be significantly increased, and the degree of increase is positively correlated with the severity of the infection.
Although CRP is one of the commonly used early indicators of systemic inflammatory response, when the body is in a state of immunosuppression, the concentration of CRP in plasma does not increase.
4. PCT diagnostic reagents have specific value in the identification of systemic and local bacterial infections
PCT is often significantly increased in the systemic inflammatory response caused by bacterial infection (especially sepsis, gram-negative bacilli), and its increased degree is positively correlated with the severity of infection.
After surgery, local infections caused by bacterial and viral infections can increase PCT, CRP, and cytokines. However, when secondary systemic infection occurs, PCT increases significantly, while CRP and cytokines decrease.
Therefore, the changes of CRP and cytokine levels are not consistent with the severity of infection. Therefore, for systemic infection, PCT is a more specific indicator. Studies have shown that the combination of CRP and PCT diagnostic reagents can improve the sensitivity of diagnosing infection.
The increase in PCT reflects an ongoing progression from healthy to the most severe states of disease (severe sepsis and septic shock).
5. PCT diagnostic reagents are of great value in the diagnosis and identification of benign and malignant tumors with secondary infection
Serum PCT concentration in most patients with benign and malignant tumors is in the normal range or slightly elevated. When complicated with infection, especially systemic infection, PCT increases significantly.
When an inflammatory mass appears, the positive rate of PCT is as high as 100%, and the increase is obvious, reaching more than 10 times the normal level.
6. The determination of PCT concentration of diagnostic reagents can help doctors determine whether patients with respiratory tract infections need antibiotics
Most respiratory infections are caused by viruses, not bacteria, but viruses can damage the airways and cause secondary infections.
Determination of PCT concentration can help doctors to determine whether patients with respiratory tract infection need antibiotics, so as to reduce unnecessary clinical application of antibiotics.
7. The use of PCT procalcitonin reagent in lower respiratory tract infection
(1) PCT is an important identification index for neonatal sepsis and septic shock
The sensitivity, specificity, accuracy and positive predictive value of PCT for the diagnosis of neonatal sepsis and septic shock were higher than those of CRP, but the negative predictive value was lower than that of CRP.
(2) Rapid PCT diagnostic reagents that can report together with blood routine
As an excellent specific indicator of bacterial infection, PCT has been recognized and valued by more and more clinics. PCT has not been well promoted and applied in clinical practice, especially in emergency department, fever clinic, and pediatrics.
20μL of trace blood, more suitable for children, the elderly and those who have difficulty in blood collection; 6-minute rapid detection, which can be reported together with the blood routine; high accuracy, and the results of professional comparison are equivalent to the industry gold standard results.
Doctors don't have to wait, they can obtain the test report of procalcitonin reagent together with the blood routine within 30 minutes, so as to make timely and accurate diagnosis and timely treatment;
After the clinical application of many users, it has not only improved the service level of the hospital, but also improved the satisfaction of patients, and has gradually been favored by more users.