Acute bacterial rhinosinusitis (ABRS) is caused by a bacterial infection of the paranasal sinuses. Symptoms include facial pain and pressure, purulent drainage, congestion and fever.
The most common bacteria associated with ABRS include Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis. Almost all cases of acute bacterial rhinosinusitis are preceded by an acute viral rhinitis (or common cold).
In the most common presentation, symptoms of a common cold develop and will resolve over the course of 7 – 10 days. In approximately 2 – 5% of cases, however, acute bacterial rhinosinusitis develops. When this happens, the cold symptoms get worse or do not start to resolve after 5 – 7 days. At this point, it is appropriate to start antibiotic therapy.
On the other hand, starting antibiotics earlier is not recommended, because the condition is probably viral. Antibiotics do nothing for viral rhinitis and the condition will usually resolve without specific treatment.