IN-VITRO ACTIVITIES OF AZITHROMYCIN AND DOXYCYCLINE AGAINST 15 ISOLATES OF CHLAMYDIA-PNEUMONIAE

Fourteen isolates of Chlamydia pneumoniae, 12 from clinically ill pati ents and 2 from subjectively healthy individuals from an area within a 400-km proximity of Gavle, Sweden, and strain IOL-207, originally fro m the eye of an Iranian child, were tested for susceptibilities to the antibiotics doxycycline and azithromycin, MICs and minimum chlamydiac idal concentrations were found to correlate well with values reported earlier by other investigators, In addition to MIC and minimum chlamyd iacidal concentration testing, testing for the viability of C. pneumon iae after exposure to antibiotic concentrations as high as 50 mg/liter was carried out by passaging antibiotic-treated, infected cell cultur es four times in the absence of antibiotics, It was found that all Chl amydia strains were viable after four passages, regardless of the init ial antibiotic concentration in the cell culture.