Though bacteria are
the most common infectious agents in sinusitis, the role of bacteria
or other infectious agents is complicated in chronic sinusitis.
They may play a direct or an indirect role.
The bacteria most
commonly implicated in sinusitis are the following:
(also called pneumococcal pneumonia or pneumococci). This bacterium
is found in between 20% and 43% of adults and children with sinusitis.
H. influenzae (a common
bacteria associated with many upper respiratory infections). This
bacterium colonizes nearly half of all children by age two, and
it causes about 25% of sinusitis cases in this group. Studies have
reported the presence of this bacterium in 22% to 35% of adult sinusitis
. Over three-quarters of all children harbor this bacterium and
it causes about 25% of sinusitis cases.
About 20% of chronic sinusitis cases are caused by Staphylococcus
aureus (commonly called Staph infection). This bacteria may be present
but is not usually the infecting agent in acute sinusitis.
Along with other bacteria,
certain anaerobic bacteria, particularly the species Peptostreptococcus,
Fusobacterium, and Prevotella, are found in 88% of cultures in chronic
sinusitis cases. (Anaerobic bacteria exist without air.)
is generally considered harmless, although it causes great discomfort
and is often very painful. When the episode becomes severe, antibiotics
generally eliminate further problems.