sinusitis may be classified in several ways based on the time span of the problem (acute subacute or chronic) and the type of inflammation (either infectious or noninfectious). acute sinus infection (also termed acute sinusitis caused by infection) is usually defined as being of less than 30 days duration. subacute sinus infection as being over 1 month but less than 3 months. chronic sinus infection as being greater than 3 months duration. there is no medical consensus on the above time periods. infected sinusitis usually is caused by uncomplicated virus infection. less frequently bacterial growth causes sinus infection and fungal sinus infection is very infrequent. subacute and chronic forms of sinus infection usually are the result of incomplete treatment of an acute sinus infection. noninfectious sinusitis is caused by irritants and allergic conditions and follows the same general time line for acute subacute and chronic as infectious sinusitis.
what are the types of sinus infections?