chemical formula a combination of symbols used to express the chemical components of a substance. empirical formula a chemical formula that expresses the proportions of the elements present in a substance.
The bacteria streptococcus pneumoniae is the most common cause of acute bacterial sinusitis. This type of bacteria can be resistant to the most common types of antibiotics at standard dosages, although there are other antibiotics that can be used to treat the condition.
Medically termed sinusitis, a sinus infection occurs when the cavities around your nose become swollen and inflamed. Sinusitis is most often caused by a virus and often lasts long after the other upper respiratory symptoms are gone. Rarely, fungus or bacteria may cause a sinus infection. Allergies, nasal polyps, a tooth infection, and a deviated septum are other ways in which sinusitis may be triggered.