Streptococcus pneumoniae Antigen Test

Hi everyone. This is Jeremy (0702919B) from TG01 posting. This post will be about a test kit used in the lab to detect Streptococcus pneumoniae. Any questions, please feel free to ask.

Streptococcus pneumoniae Antigen Test

The BinaxNOW® Streptococcus pneumoniae Test is a rapid, in vitro immunochromatographic assay. It detects S. pneumoniae antigen in the urine of patients with pneumonia and also in the cerebral spinal fluid (CSF) of patients with meningitis. Both pneumonia and bacterial meningitis pose many complications to patients, and are almost always fatal if left untreated. Thus, it is necessary for an early detection and appropriate treatment to be administered. The Streptococcus pneumoniae Antigen Test, used together with culture and other methods, can also aid in the diagnosis of both pneumococcal pneumonia and pneumococcal meningitis.

Principle

The test kit involves the use of anti-S. pneumoniae antibody and control antibody. Both antibodies are adsorbed onto a nitrocellulose membrane (the anti-S. pneumoniae antibody on the sample line, while control antibody on the control line). The antibodies are conjugated to visualizing particles that are dried onto an inert fibrous support.

The presence of pneumococcal antigen in the sample will reacts to bind anti-S. pneumoniae conjugated antibody. The resulting antigen-conjugate complexes are captured by immobilized anti-S. pneumoniae antibody, forming the Sample Line. Immobilized control antibody captures anti-species conjugate, forming the Control Line.

Results Interpretation

Positive results:

Two pink-to-purple coloured lines will be formed. This means that an antigen was detected. Specimens with low levels of antigen may give a faint sample line. Any visible line is positive.

Negative results:

Only one pink-to-purple coloured control line in the top half of the window is formed. Formation of only the control line means that detection part of the test was done correctly, however no S. pneumoniae antigen was detected.

Invalid results:

No lines are seen, or only the sample line is seen. An invalid test must be repeated.

*Read results after 15 minutes.

That is all for the test kit. Thank you for reading.