Sinuses are cavities within the body. The sinuses found in the skull are sometimes the location of bacterial infections. An infection of the sinuses is known as sinusitis. This condition is not typically life-threatening, but for those suffering through the irritating symptoms of a sinus infection, the thick yellow nasal discharge and pain of sinusitis can make life miserable. Numerous factors can cause sinusitis, but bacterial infections are the most common. Several types of bacteria are commonly associated with sinus infections.
Streptococcus Pneumoniae
Streptococcus pneumoniae is found in as many as 45 percent of those infected with sinusitis, according to Kenneth Todar, Ph.D., the author of Todar's Online Textbook of Bacteriology. It is considered a transient member of the normal flora of the upper respiratory tract. This bacterium is the culprit in cases of pneumococcal pneumonia when it infects the lungs.
Todar notes that this particular bacterium can develop antibiotic resistance through gene mutation. It grows fast and produces large amounts of cells in high densities. It can cause disease in both humans and animals, and adheres to the lining of the sinuses. Pneumococcal infections cause more deaths than any other bacterial disease for which vaccines are available, notes Todar.
Haemophilus Influenzae
According to Todar, Haemophilus influenzae bacteria are normally present in the nasal sinuses of about 75 percent of people even though they show no sign of infection. Its name is derived from the mistaken assumption that it was the cause of the influenza pandemic of 1890, though Todar notes that it was most likely a secondary invader in that particular influenza outbreak.
This bacterium was the first free-living organism to have its DNA completely decoded by scientists. It appears to cause disease in humans only. Along with sinusitis, Haemophilus influenzae can cause meningitis, ear infections and respiratory tract infections.
Moraxella Catarrhalis
The University of Maryland Medical Center explains that Moraxella catarrhalis causes up to 25 percent of all cases of sinusitis and is present in more than 75 percent of children. This bacterium is commonly associated with otitis media, or middle ear infections, as well as exacerbation of the symptoms of chronic obstructive pulmonary disease. Timothy Murphy of the Division of Infectious Diseases at the State University of New York notes that cases of sinusitis caused by the Moraxella catarrhalis bacteria are clinically indistinguishable from those arising from infection by the Haemophilus influenzae or Streptococcus pneumoniae bacteria.
References
- "Clinical Practice"; Moraxella Catarrhalis, a Human Respiratory Tract Pathogen; Timothy F. Murphy and G. Iyer Parameswaran; July 2009
- Todar's Online Textbook of Bacteriology: Streptococcus Pneumoniae
- University of Maryland Medical Center: Sinusitis Causes
- Todar's Online Textbook of Bacteriology: Haemophilus Influenzae and Hib Meningitis
