The increase in resistance of S. pneumoniae to penicillin and macrolide antibiotics has led to the need to develop a new class of antibiotics effective against resistant strains. Telithromycin has become the first representative of a new class of ketolides.

American otolaryngologists conducted a study to study the frequency of eradication of Streptococcus pneumoniae from the nasopharynx in adult patients with acute sinusitis in the treatment of ketolide with telithromycin and azithromycin.

The study involved 105 patients with acute sinusitis. A nasopharyngeal swab was taken before the start of treatment and 10 to 12 days after its start. Fifty-nine patients received azithromycin 500 mg for 3 days and 46 to 800 mg telithromycin for 5 days.

Microbiological examination of 57 patients yielded 67 cultures of etiologically significant microorganisms. Of these patients, 32 were treated with telithromycin and 25 with azithromycin. The following microorganisms have been isolated: S. pneumoniae (31 strains), Haemophilus influenzae (not type b) (13), Staphylococcus aureus (8), Streptococcus pyogenes (8) and Moraxella catarrhalis (7). The distribution of pathogens was the same in both groups.

Following treatment, the number of S. pneumoniae strains in the azithromycin group increased from 14 to 8 (by 43%), while of the remaining 8 strains, 5 were resistant to azithromycin. In the telithromycin group, the number of pneumococcal strains increased from 17 to 1 (by 94%), while the remaining strain was sensitive to both drugs. The differences between the groups were statistically significant (p less than 0.01). The frequency of eradication from other microorganisms was comparable in the two groups, and all strains were susceptible to telithromycin and azithromycin. The formation of antimicrobial resistance (an increase in the minimum inhibitory concentration of at least 2 dilutions) was observed in 5 strains (4 S. pneumoniae and 1 H. influenzae ) isolated from patients receiving azithromycin (p less than 0.05).

Thus, this study showed that telithromycin is superior to azithromycin in the frequency of eradication of S. pneumoniae from the nasopharynx in adult patients with acute sinusitis.