MICROBIOLOGY AND MANAGEMENT OF OTITIS-MEDIA

Otitis media is a complex and multifactorial condition with four defin ed stages: myringitis, acute otitis media, secretory (serous) otitis m edia and chronic otitis media. Drugs utilized in its treatment are ant ihistamines, decongestants, mucolytic agents, non-steroidal anti-infla mmatory agents, corticosteroids, vaccine therapy and antibiotics. The rationale for using antibiotics is that inflammation has been associat ed with the presence of virulent bacteria in all types of otitis media . In acute otitis media the major organisms, present are Haemophilus i nfluenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. In chr onic otitis media these organisms, plus Staphyloccocus aureus, Escheri chia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and anaerobic bacteria are all prevalent. The microbiological flora of the middle e ar in secretory otitis media is almost identical with that in acute ot itis media. Empirical therapy can be given in most instances of acute and serous otitis media. However, in cases of failure, in the immunoco mpromized and in instances of chronic otitis media, establishing the i ndividual microbiology of the inflamed middle ear is very helpful. The growing resistance of H. influenzae and M. catarrhalis to amoxycillin , due to beta-lactamase production, increases the risk of treatment fa ilure of acute and serous otitis media. By adding a beta-lactamase inh ibitor (clavulanic acid) to amoxycillin, or using second-generation ce phalosporins, clearance can be achieved. Management of chronic otitis media requires surgical correction, drainage and coverage of anaerobic bacteria with agents such as amoxycillin plus clavulanic acid, or cli ndamycin plus antimicrobials against other pathogens such as Pseudomon as spp. where present.