Long-term persistence of ciprofloxacin-resistant Haemophilus influenzae in patients with cystic fibrosis.
Ciprofloxacin has been a major advance in the treatment of chronic respiratory infections. Three patients with cystic fibrosis and colonized by 5 nontypeable Haemophilus influenzae strains exhibiting low- (MIC, 2 microg/mL) and high-level ciprofloxacin resistance (MICs, 16-32 microg/mL) are described. The patients had received several courses of ciprofloxacin. These MICs represent a decrease in ciprofloxacin susceptibility of 200-3200 times. Molecular epidemiologic methods demonstrated that 2 patients were chronically colonized by their own ciprofloxacin-resistant strains for > or = 15-17 months. Three strains showed simultaneous resistance to ampicillin and chloramphenicol by enzyme inactivation, and 2 had ampicillin resistance without beta-lactamase activity. These data suggest that the emergence and long-term persistence of ciprofloxacin-resistant H. influenzae in patients with cystic fibrosis can be a consequence of antibiotic treatment.
Campos
J
J
Centro Nacional de Microbiologia, Majadahonda, Madrid, Spain.
Román
F
F
Georgiou
M
M
García
C
C
Gómez-Lus
R
R
Cantón
R
R
Escobar
H
H
Baquero
F
F
D000328:Adult; D000668:Ampicillin Resistance; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D002702:Chloramphenicol Resistance; D002939:Ciprofloxacin / Q000627:therapeutic use*; D003550:Cystic Fibrosis / Q000382:microbiology*; D004352:Drug Resistance, Microbial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006192:Haemophilus Infections / Q000188:drug therapy*; D006193:Haemophilus influenzae / Q000187:drug effects / Q000254:growth & development; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D012150:Polymorphism, Restriction Fragment Length; D001618:beta-Lactamases / Q000378:metabolism
D000890:Anti-Infective Agents; D002939:Ciprofloxacin; D001618:beta-Lactamases