Blood diagnostics give us valuable information regarding the functioning of the body. The PCT blood test is one of the most useful tests because it provides valuable information on certain diseases and allows doctors to make correct diagnoses. The procalcitonin assay assesses the likelihood of sepsis, an often fatal bacterial infection. Inflammation triggered by the body’s release of substances that could cause harmful inflammation, resulting from a bacterial infection can lead to sepsis. If you have high blood procalcitonin levels, which is a chemical secreted by your body in the event of bacterial contamination, then it may indicate that either you have sepsis or are prone to developing it. 

What is the PCT Blood Test?

A blood test known as the PCT checks procalcitonin. Procalcitonin is the precursor hormone to calcitonin which is synthesised in the thyroid gland. Usually, procalcitonin levels are low in a healthy person but can increase substantially after bacterial infections especially the severe ones. For a procalcitonin test, blood sample is required. It measures the amount of a chemical known as procalcitonin that is produced by different types of cells in the body. Procalcitonin levels can be high if there is bacterial infection or any tissue damage.

Therefore, in case a bacterial infection is widespread or systematic, the procalcitonin levels can spike rapidly. Other conditions too can cause an increase in procalcitonin, mostly mild to moderate. However, the elevation of procalcitonin does not mean that sepsis will occur. It is just an indication that further investigation will be needed for the nature of systemic disease to be addressed.

Purpose of PCT Blood Test

The primary motive of the PCT blood test is to assist doctors in differentiating among bacterial and viral infections. While signs and symptoms of these two kinds of infections can regularly overlap, the PCT blood test aids in getting accurate prognosis, guiding physicians towards appropriate treatment plans. The procalcitonin test is helpful in differentiating between a bacterial infection and other non-bacterial causes of signs and symptoms in a critically unwell individual, as well as in the early detection of sepsis and severe bacterial infections.

When is a PCT Blood Test Needed?

When a patient is critically sick and exhibits symptoms and indications of sepsis, a severe bacterial infection, or both, a procalcitonin test may be needed. 

• When a person gets an infection, such as meningitis or pneumonia, and the cause is unknown (either bacterial or non-bacterial), the test may be requested.
• Procalcitonin levels can be useful in monitoring patients with sepsis, a potentially life-threatening condition resulting from the body's extreme response to an infection.
• When a doctor wishes to monitor antibiotic therapy and/or determine if treatment can be safely stopped, they may request a series of procalcitonin tests on a regular basis.
• In the postoperative period, a PCT blood test might be employed to detect and manage bacterial complications.
• PCT levels can help distinguish between bacterial and viral causes of respiratory infections, guiding appropriate antibiotic usage.

What Happens During the PCT Blood Test?

A blood sample is taken from a vein in the arm for the test. The collected blood sample is sent to a laboratory, where technicians analyse the procalcitonin levels. Results are usually available within a few days. The results are interpreted by doctors in the context of the patient's clinical condition and symptoms.

Uses of PCT Blood Test

This blood test is performed to determine whether you have a systemic infection, which is an infection that affects the entire body and may be the cause of your serious health condition. Your doctor can determine if you have a viral or bacterial illness by ordering a procalcitonin test. For example, a procalcitonin test is performed to determine the aetiology of bacterial or viral pneumonia. The procalcitonin test is also used for other purposes:

• One of the primary uses of the PCT blood test is to aid in the diagnosis of bacterial infections or sepsis, helping doctors choose the appropriate course of treatment.
• Monitoring procalcitonin levels in sepsis patients can help determine the severity of the condition and direct treatment plans.
• The test contributes to antibiotic stewardship by helping to avoid unnecessary antibiotic prescriptions for viral infections, thus curbing antibiotic resistance.
• PCT levels can be monitored after surgery to detect and address bacterial complications promptly.
• When a child has a urinary tract infection, PCT tests identify potential kidney infection symptoms. 

PCT Blood Test Procedure

A small amount of blood—roughly 1 millilitre, or only 2 teaspoons—is taken. A medical centre or diagnostic lab with a PCT testing facility that is fully equipped is required to perform this test. An alcohol pad is used to clean the skin. After the skin has been cleansed, the vein that is readily visible is to introduce the needle into the body. The tube that is connected to the needle and holds the serum gel is used to draw blood samples. For analysis, the blood sample is submitted to the research lab.

How to Prepare for the PCT Blood Test

No specific preparation is required for a PCT blood test. However, it is crucial to inform the doctor about any medications or supplements being taken. A PCT blood test often does not need fasting. But do adhere to any special directions that your healthcare physician may have given you.

What Do PCT Blood Test Results Mean?

The procalcitonin blood test findings are not used to assess how well any organ functions. All it tells you is whether there is a bacterial infection and how bad it is. 

Following table shows you the pct blood test normal range and elevated range with risk associated:

• Low Levels: Viral infections or noninfectious inflammatory disorders are typically linked to low procalcitonin levels. Antibiotic treatment might not be required in certain circumstances.
• Elevated Levels: A greater chance of a bacterial infection is indicated by elevated procalcitonin levels. This information will be used by medical professionals to decide on the best course of action, which may involve using antibiotics.

Conclusion

The PCT blood test stands as a valuable tool in the diagnostic procedures, aiding doctors in making informed decisions about the nature of infections. By differentiating between bacterial and viral causes, the test contributes to more targeted and effective treatment plans, ultimately benefiting patient outcomes. In light of the ongoing advancements in technology and medical research, the PCT blood test continues to provide promise for prompt and accurate diagnosis, which can result in better healthcare procedures.

FAQs

Q1. What is a normal level of PCT blood test?

Ans. A normal procalcitonin level in the blood is typically below 0 to 0.05 micrograms per litre (ug/L). Elevated levels may indicate a bacterial infection.

Q2. What happens if the PCT blood test is positive?

Ans. A positive PCT blood test result, indicating PCT blood test high level, suggests a higher likelihood of a bacterial infection. Healthcare providers may use this information to guide appropriate antibiotic treatment.

Q3. What happens if the PCT blood test is negative?

Ans. A negative PCT blood test result, with normal or low PCT blood test, suggests a lower likelihood of a bacterial infection. This may influence healthcare providers to explore non-bacterial causes for the patient's symptoms and consider alternative treatment approaches.

Q4. What is PCT normal range?

Ans. The PCT normal range in the blood is typically below 0.05 nanograms per millilitre (ng/mL). Elevated levels may indicate a bacterial infection.