A number of common childhood illnesses, including some middle ear (otitis media) and sinus infections (sinusitis), are caused by Moraxella catarrhalis bacteria. On rare occasions, this same organism may cause a blood infection (bacteremia), an eye infection (conjunctivitis), and meningitis in newborns. It is also responsible for some cases of bronchitis and pneumonia in older children and children who have problems with their immune system.
M catarrhalis ear infections and other respiratory tract illnesses are often treated with amoxicillin clavulanate. Alternative drugs include cefuroxime, cefprozil, erythromycin, azithromycin, and trimethoprim sulfamethoxazole, among others.