Pneumococcal Antigen in Serum (Mass Concentration)

Why This Test Might Be Ordered

Your healthcare provider may order this test if you have symptoms like fever, chills, or confusion that could indicate a serious bacterial infection, particularly if you have a weakened immune system or underlying health conditions. It may also be used in certain clinical settings to monitor for infection in high-risk patients.

How the Test Works

The test detects specific antigens from *Streptococcus pneumoniae* (pneumococcus) bacteria in your serum. These antigens are fragments of the bacterial cell wall that the immune system recognizes. The test uses a sensitive method to measure their concentration, helping identify infection before symptoms become severe.

Sample Collection and Preparation

A blood sample is drawn from a vein, typically in your arm. The blood is then processed to separate serum (the liquid part after clotting), which is sent to the lab for testing. This test is not typically done on urine or other body fluids.

What to Expect Before the Test

No special preparation is needed for this test. You may have some mild discomfort or bruising at the injection site, but this usually resolves quickly. If you are on blood-thinning medication, let your provider know before the test.