Itzhak Brook1, Jeffrey N Hausfeld. 1. Department of Pediatrics and Medicine, Georgetown University and George Washington University, Schools of Medicine, Washington, DC, USA. ib6@georgetown.edu
Abstract
OBJECTIVE: To evaluate the effects of subinhibitory concentrations of penicillin and telithromycin on capsular formation by Streptococcus pneumoniae. METHODS: A total of 60 isolates of S. pneumoniae, 20 susceptible, 20 intermediately resistant and 20 resistant to penicillin, were studied. All isolates were susceptible to telithromycin. RESULTS: All isolates were capsulate when grown without antibiotics. Encapsulation was lower after incubation with telithromycin as compared with penicillin in isolates susceptible to penicillin (20% versus 75%), in those intermediately resistant to penicillin (25% versus 95%) and in isolates fully resistant to penicillin (15% versus 100%) (P < 0.01). CONCLUSIONS: Telithromycin appears to be superior to penicillin in reducing the expression of the capsule by S. pneumoniae.
OBJECTIVE: To evaluate the effects of subinhibitory concentrations of penicillin and telithromycin on capsular formation by Streptococcus pneumoniae. METHODS: A total of 60 isolates of S. pneumoniae, 20 susceptible, 20 intermediately resistant and 20 resistant to penicillin, were studied. All isolates were susceptible to telithromycin. RESULTS: All isolates were capsulate when grown without antibiotics. Encapsulation was lower after incubation with telithromycin as compared with penicillin in isolates susceptible to penicillin (20% versus 75%), in those intermediately resistant to penicillin (25% versus 95%) and in isolates fully resistant to penicillin (15% versus 100%) (P < 0.01). CONCLUSIONS:Telithromycin appears to be superior to penicillin in reducing the expression of the capsule by S. pneumoniae.
Authors: Lee W Goneau; Thomas J Hannan; Roderick A MacPhee; Drew J Schwartz; Jean M Macklaim; Gregory B Gloor; Hassan Razvi; Gregor Reid; Scott J Hultgren; Jeremy P Burton Journal: MBio Date: 2015-03-31 Impact factor: 7.867