Capnocytophaga (Bacteroides ochraceus, Center for Disease Control biogroup DF-1) is associated with sepsis in granulocytopenic patients and is isolated in large numbers from the affected periodontal pockets in patients with juvenile periodontosis. The minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of 17 antimicrobial agents for 13 strains of Capnocytophaga organisms were determined. In addition, the ratio of the MBC to the MIC for each antimicrobial agent was determined for each strain. At concentrations of 1 ,ug/ml or less, penicillin, ampicillin, carbenicillin, erythromycin, and clindamycin killed 90% of the strains. At concentrations of 3.12 ,ig/ml or less, tetracycline, metronidazole, cefoxitin, and chloramphenicol killed 90% of the strains. None of the aminoglycosides tested demonstrated antibacterial activity at 50 jig/ml. Penicillin, ampicillin, carbenicillin, and cefoxitin exhibited MBC/ MIC ratios of 4 or less with all strains. Erythromycin, tetracycline, and metronidazole exhibited MBC/MIC ratios of 4 or less for 12 of 13 strains. The MICs of cephalothin and cefazolin for 90% of the strains were 25 and 50 ,tg/ml, respectively.The MBC/MIC ratios for these drugs were 4 or less for 12 of 13 and 7 of 13 strains, respectively. The MIC of cefamandole for 90% of the strains was 3.12 jig/ ml; however, only nine strains had an MBC/MIC ratio of 4 or less.The generic designation Capnocytophaga has recently been given to a group of gram-negative, gliding bacilli which are part of the normal oral flora and have been isolated in large numbers from the periodontal lesions of patients with localized juvenile periodontitis (4). These organisms are facultatively anaerobic, capnophilic, fusiform, and dysgonically fermnenting rods. Newman et al. (5) and Williams et al. (7) demonstrated in 1979 the synonymy of Capnocytophaga, Bacteroides ochraceus, and Center for Disease Control biogroup DF-1.We recently documented Capnocytophaga as the cause of sepsis in patients with malignancy complicated by profound granulocytopenia and oral mucositis (3). Since Capnocytophaga organisms appear to be opportunistic pathogens in immunosuppressed patients, and since few data are available regarding their antimicrobial susceptibility, we determined the minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of 10 clinical isolates and three reference strains of Capnocytophaga to 17 antimicrobial agents. MATERIALS AND METHODSBacteriological studies. Organisms were identified both by conventional methods (6) and by the buffered single substrate technique described by Blachman and Pickett (1). Six isolates were recovered from the blood of as many patients with granulocytopenia and malignancy. Four isolates were obtained from the periodontal pockets of patients seen in the Periodontal Clinic, University of California-Los Angeles School of Dentistry. Three strains were stock cultures of Capnocytophaga sputigena, C. ochracea, and C. gingivalis, provided by S. S. Socransky (F...
Working independently, three laboratories had recognized considerable similarity among certain strains of dysgonic, fermentative, capnophilic, surface translocating, gram-negative bacilli referred to as Capnocytophaga, Bacteroides ochraceus, and Center for Disease Control biogroup DF-1. To determine the relationship among these groups, 21 strains were exchanged and independently characterized by the three laboratories. Additionally, a fourth laboratory examined the deoxyribonucleic acid homologies of the same strains. Using methods common to dental microbiology, eight of the strains had been isolated from the gingival sulcus and periodontal lesions and identified as Capnocytophaga. Three strains isolated from blood and transtracheal aspirate had been characterized by conventional anaerobic methods and recorded as B. ochraceus. Ten strains isolated from sputum, blood, throat, spinal fluid, and tracheal aspirate had been identified as DF-1 with the methods of E. 0. King and a buffered single-substrate technique. All strains were similar in respect to colonial and microscopic morphology, surface translocation, biochemical features, gas-liquid chromatograms of metabolic end products, and deoxyribonucleic acid composition. We conclude that these biogroups should be termed Capnocytophaga species.
Seventy-three patients with bite wounds (16 patients with clenched-fist injuries, 18 with human bite wounds, and 39 with animal bites) were cultured aerobically and anaerobically. A total of 33 of 34 patients with human bites and clenched-fist injuries and 33 of 39 patients with animal bites had aerobic or facultative bacteria isolated from their wounds. A total of 224 strains of aerobic or facultative bacteria were isolated, the most frequent isolate being alpha-hemolytic streptococci (50 strains). Staphylococcus aureus was isolated from 18 wounds. Penicillin-resistant gram-negative rods were infrequently isolated (12 strains). Anaerobic bacteria were isolated in 18 of 34 human bite wounds and clenched-fist injuries and 16 of 39 animal bite wounds. A total of 88 anaerobic strains was isolated, the most common being various Bacteroides species (36 strains).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.