Acute Moraxella catarrhalis bacterial sinusitis

Acute *Moraxella catarrhalis* bacterial sinusitis is an acute infection and inflammation of the paranasal sinuses caused by the gram-negative diplococcus *Moraxella catarrhalis* It primarily affects the mucosal lining of the upper respiratory tract across both pediatric and adult populations, frequently arising as a secondary bacterial complication following a viral upper respiratory infection or ostiomeatal obstruction

It primarily affects the mucosal lining of the upper respiratory tract across both pediatric and adult populations, frequently arising as a secondary bacterial complication following a viral upper respiratory infection or ostiomeatal obstruction Pathophysiologically, mucosal swelling leads to impaired mucociliary clearance, stagnant secretions, and bacterial proliferation within the sinus cavities

Defining clinical features include persistent purulent nasal discharge, nasal obstruction, facial pain or pressure, and fever lasting beyond the typical duration of a viral illness or abruptly worsening after initial improvement

Defining clinical features include persistent purulent nasal discharge, nasal obstruction, facial pain or pressure, and fever lasting beyond the typical duration of a viral illness or abruptly worsening after initial improvement

Defining clinical features include persistent purulent nasal discharge, nasal obstruction, facial pain or pressure, and fever lasting beyond the typical duration of a viral illness or abruptly worsening after initial improvement