[Effect of macrolide antibiotics on human serum-bactericidal sensitivity of Pseudomonas aeruginosa S-6].
It is well known that long-term administration of erythromycin (EM) at a small dose is effective for persistent infections with Pseudomonas aeruginosa in diffuse panbronchiolitis or chronic bronchitis patients. Since EM is less active against P. aeruginosa in vitro, we have been interested in the mechanisms of clinical efficacy of EM in these patients. This study examines the effect of macrolide antibiotics on human serum-bactericidal sensitivity of P. aeruginosa S-6, clinically isolated from the patient with respiratory tract infection. A significant increase in serum-bactericidal sensitivity of P. aeruginosa S-6 was observed on agar containing EM of 10 micrograms/ml after incubation for 36-60 hours (p less than 0.05). The enhancement of serum sensitivity of P. aeruginosa S-6 was apparently observed even at a concentration of EM 1.5 micrograms/ml after the 48 hours incubation (p less than 0.01). Of other macrolide antibiotics used, clarithromycin (CAM) also increased the serum-bactericidal sensitivity of P. aeruginosa S-6 as well as EM, however no change in the sensitivity was found with kitasamycin, josamycin, rokitamycin and oleandomycin. The results suggest that the change of serum-bactericidal sensitivity of P. aeruginosa induced by EM or CAM may, in part, contribute to the clinical efficacy of these antibiotics against persistent pulmonary P. aeruginosa infections.
Tateda
K
K
Department of Microbiology, Toho University School of Medicine.
Furuya
N
N
Hirakata
Y
Y
Ohno
A
A
Kaneko
Y
Y
Miyazaki
S
S
Tsuji
A
A
Yamaguchi
K
K
Goto
S
S
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017291:Clarithromycin; D004917:Erythromycin / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D015610:Serum Bactericidal Test
D000900:Anti-Bacterial Agents; D004917:Erythromycin; D017291:Clarithromycin