infectious diseases
Moraxella catarrhalis Infection
Introduction
Moraxella catarrhalisis a gram-negative diplococcus that causes ear and upper and lower respiratory infections. M. catarrhalis(formerly known asBranhamella catarrhalis) is a frequent cause of Otitis Media (Acute) in children Acute and chronic Sinusitis at all ages Lower respiratory infection in adults with chronic lung disease It is the second most common bacterial cause of Chronic Obstructive Pulmonary Disease (COPD) exacerbations after nontypeable Overview of Pneumonia resembles pneumococcal pneumonia. Although Bacteremia is rare, half of patients die within 3 months because of intercurrent diseases. The prevalence ofM. catarrhaliscolonization depends on age. About 1 to 5% of healthy adults have upper respiratory tract colonization. Nasopharyngeal colonization withM. catarrhalisis common throughout infancy, may be increased during winter months, and is a risk factor for acute otitis media; early colonization is a risk factor for recurrent otitis media. Substantial regional differences in colonization rates occur. Living conditions, hygiene, environmental factors (eg, household smoking), genetic characteristics of the populations, host factors, and other factors may contribute to these differences. The organism appears to spread contiguously from its colonizing position in the respiratory tract to the infection site. There is no pathognomonic feature ofM. catarrhalisotitis media, acute or chronic sinusitis, or pneumonia. In lower respiratory disease, patients have increased cough, purulent sputum production, and increased dyspnea. These gram-negative diplococci resembleNeisseriaspecies but can be readily distinguished by routine biochemical tests after culture isolation from infected fluids or tissues. All strains now produce beta-lactamase. The organism is generally susceptible to beta-lactam/beta-lactamase inhibitors, sulfamethoxazole, tetracyclines, extended-spectrum oral cephalosporins, aminoglycosides, macrolides, and fluoroquinolones. 