Microbiological Evaluation of Role of Moraxella Catarrhalis in Respiratory Infections

Abstract

M.catarrhalis was once thought to be a non pathogenic, a number of reports have documented a wide spectrum of clinical diseases due to this organism. In particular M.catarrhalis is a significant cause of respiratory infections in children and is frequently associated with respiratory tract infections in adults with underlying lung disease This prospective study included 100 patients from those attended

the out patient clinic of pediatric and chest department of Tanta

University Hospital diagnosed clinically as acute pharyngitis (30 cases)

•• and AECOPD (70 cases). Naspharyngeal swabs and sputum samples were obtained and inoculated on blood agar at Co2 of 5-10% for 24 hs at

35 C0

Gram stain and biochemical tests were also done and confirmed by

Senstitre Automated Microbiology System (SAMS).

Identification of M.catarrhalis was found is 3 cases of patient with acute exacerbation of chronic pulmonary disease (4.3%) and 5 cases of acute pharyngitis (16.7%). . The study also included 50 healthy individuals (control group), nasopharyngeal colonization of M.catarrhalis was found in 11 of them (22%). 75% of pathogenic strains of M.catarrhalis have resistance to killing by human sera which considered as a virulence factor whereas 66.7 of colonizing strains were also serum resistant.