Streptococcus pneumoniae antigen - urine, CSF

Last updated: Tuesday, 07, August, 2007
Item Process
Specimen

Midstream or 'clean catch' urine. catheter or bladder aspirate specimen in a sterile container; CSF (See Cerebrospinal fluid examination).

Method

Immunochromatography

Application

In conjunction with microscopy and culture of respiratory tract specimens, testing of urine may assist in the diagnosis of pneumococcal pneumonia in adults. Testing of CSF is an adjunct to microscopy and culture in the diagnosis of meningitis due to Streptococcus pneumoniae.

Interpretation

Detection of Streptococcus pneumoniae antigen in the urine of an adult with pneumonia is suggestive that this is the aetiologic agent. Occasional false positives occur. The test is most sensitive in cases of severe and/or invasive disease. A negative test does not exclude infection. In children, use of this test does not distinguish between naso-pharyngeal carriage of the organism and lower respiratory tract infection.

Detection of Streptococcus pneumoniae antigen in CSF of a patient with meningitis suggests that this is the causative organism.

Reference

Smith DM et al. J Clin Microbiol 2003 41(7); 2810-2813