Streptococcus pneumoniae

Streptococcus pneumoniae (also known as pneumococcus) is a Gram-positive, alpha-hemolytic, facultative anaerobic member of the genus Streptococcus. They are usually found in pairs (diplococci) and are the main cause of community-acquired pneumonia and meningitis in children and the elderly, and of septicemia in those infected with HIV.

Morphology

Streptococcus pneumoniae are Gram-positive, lancet-shaped cocci (elongated spheres) usually appearing in pairs, known as diplococci. They are non-motile and do not form spores.

Pathogenesis

Streptococcus pneumoniae is the main cause of community-acquired pneumonia and meningitis in children and the elderly, and of septicemia in those infected with HIV. The organism also causes many types of pneumococcal infections other than pneumonia. These invasive pneumococcal diseases include bronchitis, rhinitis, acute sinusitis, otitis media, conjunctivitis, meningitis, sepsis, osteomyelitis, septic arthritis, endocarditis, peritonitis, pericarditis, cellulitis, and brain abscess.

Prevention

Prevention of Streptococcus pneumoniae infection is an active area of research. Vaccines have been developed and are in use, and many more are under development. Pneumococcal conjugate vaccine and pneumococcal polysaccharide vaccine are two types of vaccines in use.

Treatment

Treatment is with antibiotics, such as penicillin, clindamycin, or vancomycin.

See also

• List of bacterial genera named after personal names
• Pneumococcal infection
• Pneumococcal vaccine

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  Streptococcus pneumoniae under a microscope
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  Streptococcus pneumoniae colonies on agar plates
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  Streptococcus pneumoniae
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  Diagnostic algorithm of possible bacterial infection