Streptococcus pyogenes antibiotic therapy

Mild cases, characterised by pinkness or infection of the eardrum, often resolve spontaneously and need only analgesia emd observation. They are normally viral. A bulging, inflamed eardrum indicates bacterial otitis media usually due to Streptococcus pneumoniae, Haemophilus influenzae, Moraxella (Bran-hamella) catarrhalis. Streptococcus pyogenes (Group A) or Staphylococcus aureus. Amoxicillin or co-amoxiclav is satisfactory, but the clinical benefit of antibiotic therapy is very small when tested in controlled trials. Chemotherapy has not removed the need for myringotomy when pain is very severe, and also for later cases, as sterilised pus may not be completely absorbed and may leave adhesions that impair hearing. Chronic infection presents a similar problem to that of chronic sinus infection, above. 

Azithromycin, an azalide macrolide antibiotic (500 mg p.o. as a single dose on day 1, followed by 250 mg daily on days 2 to 5 total accumulation dose is 1.5 g), is indicated in the treatment of acute bacterial exacerbations of chronic obstructive pulmonary disease caused by Haemophilus influenzae, Moraxella (Branhamella) catarrhalis, or Streptococcus pneumoniae mild community-acquired pneumonia caused by H. influenzae or S. pneumoniae uncomplicated skin and skin-structure infections caused by Staphylococcus aureus, Streptococcus pyogenes, or S. agalactiae second-line therapy of pharyngitis or tonsillitis caused by S. pyogenes and in nongonococcal urethritis or cervicitis caused by Chlamydia trachomatis. 

A more expanded list of MICs (Table III) affirms the superiority of the in vitro antibacterial spectrum of cefaclor over that of cephalexin (Preston and Wick, 1974). The in vitro spectra of cefaclor and its p-hydroxy derivative (123n) appear in Table IV. The data are comparable for the two antibiotics (D. A. Preston, unpublished data). Oral therapy of mice experimentally infected with Streptococcus pyogenes, S. pneu- ... 

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