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V L Sutter

Publications and source records attributed to V L Sutter.

89 records · Page 5Linked to original sources

Rifampin-blood-agar as a selective medium for the isolation of certain anaerobic bacteria.

A selective medium which allows detection of relatively small numbers of Fusobacterium varium in fecal specimens is described. Blood-agar containing 50 mug of rifampin per ml inhibits the growth of many species of Bacteriodes and of F. fusi-forme/nucleatum but allows good growth of F. varium and most strains of F. mortiferum. Quantitative cultures of 11 fecal specimens were done on rifampin and other selective and nonselective media. F. varium was recovered in counts of 10(6) and 10(7) per gram from two specimens on rifampin only. A third specimen yielded 10(10)F. varium on several media, including rifampin. Some Eubacterium and Clostridium species also grew on rifampin, and these ordinarily were distinguished from the Fusobacterium by colony morphology. This medium is of value in fecal flora studies and should be useful with other kinds of specimens where mixtures of organisms are common.

Agar↗

Comparison of selective media for isolation of presumptive group D streptococci from human feces.

Pfizer Selective Enterococcus (PSE) agar, a medium containing bile, sodium azide, and esculin, was evaluated for its sensitivity and selectivity for detection and enumeration of presumptive group D streptococci in human feces. SF broth and SF broth plus agar (1.5%), representing selective media in common use, were studied simultaneously. Presumptive group D streptococci were recovered on PSE agar from the feces of all 25 subjects. No growth was observed in 8% of specimens in SF broth. No gram-negative organisms were recovered in any medium. PSE agar has the advantages of selecting out Streptococcus bovis, earlier appearance of distinctive reactions, and lack of requirement for special incubation temperature.

Agar↗

Effect of bile and desoxycholate on gram-negative anaerobic bacteria.

The bile tests for characterizing gram-negative anaerobic bacilli were reevaluated in prereduced anaerobically sterilized peptone-yeast-glucose broth, in thioglycollate broth, and on blood agar plates. Blood agar plates were unsatisfactory. The combination of 20% bile with 0.1% desoxycholate inhibited Fusobacterium, Bacteroides melaninogenicus, and B. oralis and sometimes Sphaerophorus necrophorus, but not B. fragilis or other Sphaerophorus species studied. Ten per cent bile with 0.05% desoxycholate was less satisfactory. There was no significant difference between fresh and commercial powdered bile. Desoxycholate (0.1% in thioglycollate broth) inhibited B. fragilis, Fusobacterium, B. melaninogenicus, B. oralis, and S. necrophorus, but not S. varius or S. mortiferus/S. ridiculosus. The bile and desoxycholate tests are simple to perform and helpful for characterization and classification of gram-negative anaerobic bacilli.

Animals↗

Identification of Pseudomonas species isolated from hospital environment and human sources.

Methods and procedures are described for the identification of aerobic pseudomonads isolated from clinical specimens. Fluorescence is used as a means of primary differentiation. Final identification is based on the observation of characteristics such as flagellation, storage of intracellular fat, growth at 4 C and at 41 C, denitrification, gelatin hydrolysis, arginine dihydrolase activity, and oxidase activity. The value of this schema to the diagnostic laboratory is discussed.

Bacteriological Techniques↗

In vitro activity of cefoxitin and parenterally administered cephalosporins against anaerobic bacteria.

The in vitro activity of cefoxitin against 221 recent isolates of anaerobic bacteria was compared with that of cefamandole and cefuroxime by the agar dilution technique. At achievable serum levels of 32 micrograms/ml, all three drugs were active against most groups of anaerobic bacteria tested. Cefoxitin was active against most strains of the Bacteroides fragilis group, whereas cefamandole and cefuroxime were relatively ineffective. Cefoxitin was least active against Clostridium species other than Clostridium perfringens, whereas cefamandole was very active and cefuroxime moderately active. A review of recent in vitro studies with cefoxitin and parenterally administered cephalosporins indicates that cefoxitin is the most active compound against the B. fragilis group and is least active against Clostridium species other than C. perfringens.

Bacteria, Anaerobic↗

Gram-negative anaerobic bacilli: their role in infection and patterns of susceptibility to antimicrobial agents. I. Little-known Bacteroides species.

The role in infection and the patterns of susceptibility to antimicrobial agents of 17 infrequently reported species of Bacteroides were studied. The findings of this research are summarized, and the literature dealing with recovery of these species from both the normal flora and infections of humans is reviewed. During a six-year period, 22% of 679 specimens from infections due to anaerobic bacteria that were studied by the authors yielded one or more of these "other Bacteroides species" (OBS). The most commonly isolated OBS were Bacteroides ruminicola subspecies brevis (63 patients), Bacteroides ureolyticus (38), Bacteroides bivius (26), and Bacteroides disiens (17). Appreciable resistance of some isolates to the beta-lactam antibiotics, erythromycin, and the tetracyclines was noted, whereas all strains were inhibited by chloramphenicol and metronidazole and almost all were inhibited by clindamycin. The data indicate that OBS are present in infection much more often than has been reported previously. The resistance of certain strains to some commonly used antimicrobial agents may necessitate a reassessment of the initial, empiric therapy of infections due to anaerobic bacteria.

Abdomen↗

Gram-negative anaerobic bacilli: Their role in infection and patterns of susceptibility to antimicrobial agents. II. Little-known Fusobacterium species and miscellaneous genera.

Twenty infrequently reported species of gram-negative anaerobic bacilli other than Fusobacterium nucleatum, Fusobacterium necrophorum, and members of the genus Bacteroides were studied with regard to their role in infection and their susceptibility to antimicrobial agents. In addition, the literature regarding the recovery of these organisms from both the normal flora and infections of humans was reviewed. During a six-year period at the Wadsworth Clinical Anaerobic Bacteriology Research Laboratory (Veterans Administration Wadsworth Medical Center, Los Angeles, Calif.), 39 (6%) of 679 specimens obtained from anaerobic infections yielded "other gram-negative anaerobic bacilli" (OGNAB). Fusobacterium naviforme, Fusobacterium gonidiaformans, Fusobacterium varium, Fusobacterium mortiferum, and Fusobacterium russii were the most commonly isolated OGNAB. Most of the OGNAB tested were resistant to erythromycin, and most strains, except for F. varium, were susceptible to beta-lactam antibiotics and clindamycin. Chloramphenicol and metronidazole were active against all strains of OGNAB tested. Certain Fusobacterium species are undoubtedly previously unrecognized members of the normal flora of the oropharynx, upper respiratory tract, or urogenital tract and may be present in infections derived from these floras.

Adult↗

Frequency of occurrence and antimicrobial susceptibility of bacterial isolates from the intestinal and female genital tracts.

In the selection of empiric therapy for infections of the female genital tract and intraabdominal infections in humans, the requisite information includes (1) the frequency of isolation of bacterial species dominant in the normal gastrointestinal and female genital tracts and in intraabdominal and female genital tract infections and (2) the in vitro susceptibilities of the dominant species to drugs that may be used against them (e.g., penicillin G, cefoperazone, cefoxitin, chloramphenicol, clindamycin, and metronidazole). The predominant bacteria in fecal contents are not necessarily those most frequently found in infections. Intraabdominal and perirectal infections are usually polymicrobial, resulting from mixtures of facultative species (coliforms and streptococci) and anaerobes. The predominant bacteria of the normal vagina and cervix are lactobacilli, facultative streptococci, Peptococcus species, and Peptostreptococcus species. Most infections of the female genital tract are due to mixtures of facultative enteric bacilli, streptococci, and anaerobes (Peptococcus and Peptostreptococcus species, Bacteroides fragilis, Bacteroides disiens, Bacteroides melaninogenicus, Bacteroides bivius, and Bacteroides asaccharolyticus). Of the antibiotics tested, clindamycin appears the most active against many of the groups of bacteria isolated.

Abdomen↗

Anaerobes as normal oral flora.

The human mouth provides a suitable habitat for numerous bacterial genera. Anaerobic genera or genera that include anaerobic members found in the oral cavity are Actinomyces, Arachnia, Bacteroides, Bifidobacterium, Eubacterium, Fusobacterium, Lactobacillus, Leptotrichia, Peptococcus, Peptostreptococcus, Propionibacterium, Selenomonas, Treponema, and Veillonella. The incidence of anaerobes varies with age of the individual and with specific sites sampled. In edentulous infants, the incidence of anaerobes is relatively low. In adults, anaerobes are invariably present but are more prevalent in samples from the gingival sulcus than they are in samples from the gingival margin, tooth surfaces, buccal mucosa, tongue, or saliva. In samples from the healthy gingival sulcus, anaerobic, gram-positive bacilli are found in the range of 5%-14%; gram-negative bacilli in the range of 13%-29%; Veillonella in the range of 2%-8%; and gram-positive cocci in the range of 1%-15% of the cultivable flora. From marginal plaque and plaque from the tooth surface, gram-positive bacilli, gram-positive cocci, and Veillonella appear to be the predominant anaerobes. In saliva, Veillonella are the most numerous anaerobes.

Actinomyces↗