title: In-vitro activity of synercid and related drugs against Streptococcus oralis isolated from septicaemia and endocarditis cases.
abstract: OBJECTIVE
  The increase in resistance to gram positive organisms and seriousness of infective endocarditis, makes it necessary to look for an alternate treatment.
  
  
  METHODS
  In-vitro activity of synercid was compared with penicillin, amoxycillin, teicoplanin, vancomycin, clindamycin and erythromycin.
  
  
  RESULTS
  Synercid showed minimum inhibitory concentrations (MIC) within the narrow range of 0.06 - 0.5 mg/l. MIC50 and mode values were both 0.25 mg/l. There was just two-fold difference between the MIC50 (0.25 mg/l) and the MIC90, (0.5 mg/l). Although the MICs of synercid for S. oralis were relatively high compared to penicillin, clindamycin, erythromycin and teicoplanin, the in-vitro bactericidal activity of synercid was much greater. Synercid MBC values were < 4 mg/l for most of the isolates, except for one of 16 mg/l and the other >64 mg/l. Killing curve was performed on six isolates of S. oralis from infective endocarditis, two from septicaemia patients and two from the oral flora of normal individuals.
  
  
  CONCLUSIONS
  Synercid showed superior bactericidal activity when compared to penicillin and vancomycin against all ten isolates of S. oralis tested. Synercid was bactericidal (99.9% kill) against all ten isolates of S. oralis within six hours of contact.
authors.affiliation: Department of Microbiology, College of Medicine, Sultan Qaboos University, P.O.Box: 35, Postal Code: 123, Muscat, Sultanate of Oman.
authors.forename: A M
authors.initials: AM
authors.lastname: Rafay
keywords: amoxycillin; clindamycin; erythromycin; penicillin; streptococcus oralis; synercid; teicoplanin; vancomycin
references.citation: J Hyg (Lond). 1938 Nov;38(6):732-49
references.pmid: 20475467
references.citation: J Antimicrob Chemother. 1992 Jul;30(1):27-37
references.pmid: 1331019
references.citation: Infect Dis Clin North Am. 1989 Dec;3(4):901-13
references.pmid: 2687368
references.citation: J Antimicrob Chemother. 1997 May;39 Suppl A:1-6
references.pmid: 9511055
references.citation: J Med Microbiol. 1991 Dec;35(6):367-72
references.pmid: 1753394
references.citation: J Antimicrob Chemother. 1992 Jul;30 Suppl A:15-8
references.pmid: 1399945
references.citation: Br Heart J. 1988 Jan;59(1):62-8
references.pmid: 3342151
references.citation: J Med Microbiol. 1976 Aug;9(3):275-302
references.pmid: 785000
references.citation: J Antimicrob Chemother. 1987 Sep;20 Suppl A:7-15
references.pmid: 3316164
references.citation: Antimicrob Agents Chemother. 1991 Mar;35(3):553-9
references.pmid: 1903912
references.citation: Br Heart J. 1983 Dec;50(6):513-9
references.pmid: 6651993
references.citation: J Antimicrob Chemother. 1992 Jul;30 Suppl A:53-8
references.pmid: 1399951
references.citation: J Antimicrob Chemother. 1997 Jul;40(1):135-6
references.pmid: 9249217
references.citation: J Antimicrob Chemother. 1992 Jul;30 Suppl A:39-44
references.pmid: 1399949
references.citation: Infect Dis Clin North Am. 1989 Dec;3(4):915-29
references.pmid: 2687369
references.citation: J Antimicrob Chemother. 1992 Jul;30 Suppl A:83-94
references.pmid: 1328138
references.citation: Antimicrob Agents Chemother. 1994 Sep;38(9):2065-72
references.pmid: 7811020
references.citation: J Antimicrob Chemother. 1987 May;19(5):585-90
references.pmid: 3112093
references.citation: J Med Microbiol. 1993 Sep;39(3):179-82
references.pmid: 8366515
references.citation: J Antimicrob Chemother. 1992 Jul;30 Suppl A:1-8
references.pmid: 1399940
references.citation: J Antimicrob Chemother. 1992 Jul;30 Suppl A:9-14
references.pmid: 1399955