It may also produce sinusitis, otitis, arthritis and bone infections. S. pneumoniae is the major cause of bacterial pneumonia in adults. Its virulence is dictated by its capsule. Ab complexes on basement membrane of kidney glomeruli. Anaerobic streptococci may cause genital, brain or abdominal infections.
Abs are important in host defense.
These organisms are widely distributed in nature. To confirm the presense of S. pyogenes , throat swabs are used. For S. pneumoniae , sputum or blood samples are taken. Useful characteristics for differentiation include the pattern of hemolysis, bacitracin resistance or sensitivity and optochin resistance or sensitivity. Immunologically-based rapid test kits are often employed.