Moraxella Catarrhalis Infection

An infection caused by a gram-negative aerobic coccus, Moraxella catarrhalis, which is morphologically and biochemically similar to Neisseria

Sinusitis, bronchitis, otitis and, rarely, pneumonia

Bacteremia and meningitis have also been reported in immunocompromised patients

Culture

The organism frequently colonizes the respiratory tract, and differentiation of colonization from infection can be difficult

If M catarrhalis is the predominant isolate, therapy should be directed against it

Amoxicillin-clavulanate, ampicillin-sulbactam, trimethoprim-sulfamethoxazole, ciprofloxacin, and second- and third-generation cephalosporins

Treatment is similar to that for Haemophilus infections (see Haemophilus Infections)

Typically produces beta-lactamase and, therefore, is usually resistant to ampicillin and amoxicillin