Final answer:
Chronic sinusitis is diagnosed when sinusitis symptoms such as inflammation and nasal obstruction persist for 1-3 months. It often follows an initial infection and can be caused by various bacteria, including S. pneumoniae, H. influenzae, and M. catarrhalis.
Step-by-step explanation:
Chronic sinusitis is present when symptoms progress over 4-12 weeks (1-3 months). Sinusitis involves infection and inflammation within the paranasal sinuses and is often accompanied by rhinitis, together termed rhinosinusitis. The most common microbial causes include bacteria such as S. pneumoniae, H. influenzae, and M. catarrhalis.
When the condition persists beyond the acute phase (less than four weeks) and continues to show symptoms for 1-3 months, it is classified as chronic. Sinusitis and other respiratory infections like rhinitis, pharyngitis, and laryngitis typically manifest through an acute inflammatory response, with each condition presenting its specific signs and symptoms.
Rhinitis usually presents with nasal congestion, runny nose, and sneezing; sinusitis may include symptoms like nasal obstruction, facial pain or pressure, and a reduced sense of smell; pharyngitis typically involves a sore throat; and laryngitis may result in voice loss due to inflammation interfering with vocal cord functions.