Complete Blood Count (CBC) Test

The Complete Blood Count (CBC) is a common blood test that measures the different cells circulating in your blood, including red blood cells, white blood cells, and platelets, to help evaluate your overall health.

The Bacillus anthracis pXO2 DNA test is a specialized molecular test that detects the presence of DNA from Bacillus anthracis, the bacteria that causes anthrax. This test specifically looks for the pXO2 plasmid, which is one of two key genetic elements (plasmids) that the anthrax bacteria need to cause disease. The test is performed using Nucleic Acid Amplification (NAA) technology, which can detect even small amounts of bacterial DNA with high accuracy.

Your doctor may order this test as part of a routine checkup, to investigate symptoms such as fatigue, weakness, fever, or unusual bruising, to help diagnose conditions like anemia or infection, or to monitor how a treatment is working over time.

This test is ordered when a blood culture (a test to detect bacteria in the blood) has already shown growth of organisms that may be Bacillus anthracis. Not all Bacillus bacteria cause anthrax—some are harmless environmental bacteria. This confirmatory test helps determine whether the bacteria found in the blood culture is actually the dangerous anthrax bacterium.

The test is performed by drawing a small sample of blood from a vein, usually in your arm. A healthcare professional cleans the site, inserts a thin needle, and collects the sample into a tube, which typically takes only a few minutes.

A healthcare provider collects a blood sample from a vein in your arm. The sample is then sent to a laboratory where technicians use specialized molecular techniques to detect the specific pXO2 DNA sequence unique to Bacillus anthracis. The test does not require probe detection and uses nucleic acid amplification methods to identify the bacterial genetic material.

Results show whether your blood cell counts fall within normal ranges. Values that are too high or too low can point to conditions such as infection, anemia, inflammation, or clotting problems, and your doctor will interpret them together with your symptoms and medical history.

A 'Positive' result means that Bacillus anthracis DNA was detected in your blood sample, which confirms an anthrax infection. This is a serious finding that requires immediate medical treatment. A 'Negative' result means that no anthrax bacteria DNA was detected, suggesting the bacteria found in the initial culture is not anthrax. Your healthcare provider will interpret these results in context with your symptoms and other test findings.