PCT: What It Is, Low Levels, High Levels, and Treatment

The Procalcitonin test, known as PCT, is used to measure the level of procalcitonin in the blood. It is an important indicator in cases of bacterial infection and the development of sepsis. In these two situations, where the body’s defense cells are intensely activated, procalcitonin levels typically peak between the second and fourth hours. PCT is the value that indicates the rate at which infection or sepsis spreads in the bloodstream. In addition to these, conditions such as meningitis, tissue tumors, and organ rejection after organ transplantation can also lead to elevated PCT levels, requiring medical supervision throughout the process.

What Should the PCT Value Be?

In a person with normal bodily functions and a properly functioning hormonal system, procalcitonin, or its precursor calcitonin, is quickly converted into calcitonin. As a result of this mechanism, the PCT value remains low. In healthy individuals, the PCT value is typically below 0.1 µg/l. If the PCT value exceeds 0.25 ng/mL, an infection is suspected. The body’s condition in relation to sepsis can be evaluated as follows:

• Between 0–0.05 µg/L: Normal
• Below 0.5 µg/L: Low risk of sepsis
• Between 0.5–2 µg/L: Possible sepsis
• Between 2–10 µg/L: Moderate to high risk of sepsis
• Above 10 µg/L: High risk of sepsis

What Are the Symptoms of Low PCT?

Since high PCT values indicate bacterial infections and sepsis, a low PCT value does not suggest an adverse condition. In fact, it indicates that there is no bacterial infection or sepsis or tissue damage. If a person feels unwell but the PCT value is low, other causes of the discomfort should be investigated. A decrease in PCT levels during an infection or illness suggests that the treatment is progressing successfully.

What Are the Causes of Low PCT?

A low PCT value generally does not reflect a negative situation. It indicates the absence of infection or sepsis, which is a desirable condition. As it is known, PCT levels are high in cases of bacterial infections and sepsis. If the PCT value is low but there is still fatigue or illness, it could be due to a viral infection. A decrease in PCT levels after the onset of the illness indicates that the infection is bacterial in origin and that the treatment is progressing well. In summary, a low PCT value is an important diagnostic result suggesting that many diseases are not present.

How Is Low PCT Treated?

A low PCT value does not indicate any negative condition when examining hemogram test results. Rather than focusing on the low PCT value, concern should arise when the PCT value is high, indicating the possibility of infection or other disorders. Therefore, in cases of low PCT, treatment should not be immediately necessary, but the person's overall condition should be assessed. If there is suspicion of illness, further tests, X-ray results, and the individual’s health history should be reviewed to develop a specific treatment plan.

What is PCT Elevation?

A PCT level higher than 0.5 µg/L is considered an indicator of bacterial infection or sepsis in tissues. In the presence of infection in the body, the first step is to start antibacterial treatment. PCT levels vary according to the intensity and extent of the infection. In severe bacterial infections like sepsis and meningitis, PCT levels can reach their highest points. If treatment is not started early in cases of sepsis and multiple tissue or organ damage, the process can end in severe consequences. Therefore, the process should be carefully monitored. The duration of elevated PCT and the reduction observed during the treatment process can be tracked step by step, allowing the treatment of many diseases to be monitored. If necessary, other blood tests, bacterial culture test results, and imaging results such as X-rays should also be monitored and evaluated.

What Are the Symptoms of High PCT?

High PCT is an alarm signal for many bacterial infections and conditions in the body, and there are some specific symptoms related to it. These symptoms include:

• Excessive sweating
• Damp skin
• Unexplained pain and discomfort
• Increased respiratory rate
• Decreased frequency of urination
• Palpitations
• Hypotension (low blood pressure)
• Brain fog (mental confusion) and concentration difficulties

If these symptoms are present in the patient, the situation should be promptly and clearly communicated to the healthcare professionals by the patient or their relatives. In cases of cardiological conditions or tissue rejection, the patient is managed with a complex treatment plan.

How is High PCT Treated?

The elevated PCT value in the body can arise due to various causes. To effectively lower PCT, the source of the infection or disorder must first be identified. The patient undergoes a physical examination by a physician, and their medical history is taken. If necessary, additional blood tests and imaging tests such as X-rays may also be requested. Once the cause of high PCT is identified, treatment begins.

If the cause of high PCT is a bacterial infection, a bacterial culture test is first requested. Based on this, antibiotic treatment is started. If inflammation is present in tissues and organs, abscesses should be carefully cleaned. For this procedure, drainage can be applied to the abscessed area using microsurgical methods. In cases where tumors and chronic diseases cause high PCT, the treatment process is shaped according to the diagnosis.

High PCT in complex cases is not treated as a standalone issue but as part of the treatment for the underlying disease. For example, in treatments that require chemotherapy for conditions like cancer, a holistic treatment approach is adopted, considering all body systems together. In cases like burns, the treatment is tailored according to the severity of the burn, considering factors such as nutrition and fluid balance. Ensuring adequate protein intake and maintaining electrolyte balance are crucial parts of the treatment.

The symptoms indicating high PCT are also signs of many diseases and infections, signaling the need for early intervention. If you notice these symptoms in yourself and particularly if you have risk factors like a medical history of certain diseases, do not delay getting examined. Schedule an appointment with our healthcare facility and take the opportunity for timely and early intervention to regain your health.

What Causes High PCT?

High PCT, caused by bacterial infections and conditions, is the most significant indicator of certain illnesses. The following conditions can cause elevated PCT levels in the body:

• Sepsis and tissue and organ damage
• Burns from the first degree onward
• Pancreatitis (inflammation of the pancreas)
• Severe trauma
• Endocarditis (inflammation of the heart)
• Meningitis (inflammation of brain tissues)
• Severe urinary tract infections, especially in children
• Decreased heart's ability to pump blood, resulting in inadequate delivery of oxygen and blood to tissues
• Tissue incompatibility and rejection following organ transplantation
• Infections following tumors and tumor spread
• Infections occurring after surgical intervention or operations

All of these conditions are emergencies that require rapid treatment. Additionally, it should be noted that PCT can sometimes rise without being related to infection. In cases where blood oxygen levels are low, PCT can also be elevated. Sudden PCT spikes can be observed in individuals experiencing allergic asthma attacks. PCT levels have also been observed to rise during flare-ups in COPD patients. Pneumonia and respiratory system disorders related to the lungs are also factors that can increase PCT. High altitude, which increases oxygen levels in the body, can also raise PCT. Heart failure and cardiac arrest can also elevate PCT, even if not caused by infection.