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D M Citron

Publications and source records attributed to D M Citron.

At least 37 records · Page 2Linked to original sources

Survival of aerobic and anaerobic bacteria in purulent clinical specimens maintained in the Copan Venturi Transystem and Becton Dickinson Port-a-Cul transport systems.

Recovery of aerobic and anaerobic bacteria from clinical specimens maintained in the Copan Venturi Transystem and the Becton Dickinson Port-a-Cul transport was assessed. Of 54 anaerobes, 53 were recovered after 4 h, and 52 were recovered after 24 h, from both systems. After 48 h, 45 and 50 were recovered from the two systems, respectively.

Bacteria, Aerobic↗

Bacteriologic analysis of infected dog and cat bites. Emergency Medicine Animal Bite Infection Study Group.

BACKGROUND AND METHODS: To define better the bacteria responsible for infections of dog and cat bites, we conducted a prospective study at 18 emergency departments. To be eligible for enrollment, patients had to meet one of three major criteria for infection of a bite wound (fever, abscess, and lymphangitis) or four of five minor criteria (wound-associated erythema, tenderness at the wound site, swelling at the site, purulent drainage, and leukocytosis). Wound specimens were cultured for aerobic and anaerobic bacteria at a research microbiology laboratory and, in some cases, at local hospital laboratories. RESULTS: The infected wounds of 50 patients with dog bites and 57 patients with cat bites yielded a median of 5 bacterial isolates per culture (range, 0 to 16) at the reference laboratory. Significantly more isolates grew at the reference laboratory than at the local laboratories (median, 1; range, 0 to 5; P<0.001). Aerobes and anaerobes were isolated from 56 percent of the wounds, aerobes alone from 36 percent, and anaerobes alone from 1 percent; 7 percent of cultures had no growth. Pasteurella species were the most frequent isolates from both dog bites (50 percent) and cat bites (75 percent). Pasteurella canis was the most common isolate of dog bites, and Past. multocida subspecies multocida and septica were the most common isolates of cat bites. Other common aerobes included streptococci, staphylococci, moraxella, and neisseria. Common anaerobes included fusobacterium, bacteroides, porphyromonas, and prevotella. Isolates not previously identified as human pathogens included Reimerella anatipestifer from two cat bites and Bacteroides tectum, Prevotella heparinolytica, and several porphyromonas species from dog and cat bites. Erysipelothrix rhusiopathiae was isolated from two cat bites. Patients were most often treated with a combination of a beta-lactam antibiotic and a beta-lactamase inhibitor, which, on the basis of the microbiologic findings, was appropriate therapy. CONCLUSIONS: Infected dog and cat bites have a complex microbiologic mix that usually includes pasteurella species but may also include many other organisms not routinely identified by clinical microbiology laboratories and not previously recognized as bite-wound pathogens.

Adolescent↗

Activities of gemifloxacin (SB 265805, LB20304) compared to those of other oral antimicrobial agents against unusual anaerobes.

The activities of gemifloxacin (SB 265805, LB20304) and comparator agents were determined by an agar dilution method against 419 clinical strains of less-commonly identified species of anaerobes. Gemifloxacin was generally more active than trovafloxacin against gram-positive strains by one to two dilutions. Peptostreptococci (Peptostreptococcus asaccharolyticus, Peptostreptococcus magnus, Peptostreptococcus micros, and Peptostreptococcus prevotii) and Porphyromonas spp. (Porphyromonas asaccharolytica, Porphyromonas canoris, Porphyromonas gingivalis, and Porphyromonas macacae) were all susceptible to </=0.25 microgram of gemifloxacin per ml. The MICs of gemifloxacin at which 90% of the following strains were inhibited (MIC(90)s) were </=2 microgram/ml: Actinomyces israelii, Actinomyces odontolyticus, Clostridium innocuum, Clostridium clostridioforme, Anaerobiospirillum spp., Bacteroides tectum, Bacteroides ureolyticus, Bacteroides gracilis (now Campylobacter gracilis), Prevotella intermedia, Prevotella heparinolytica, and the Prevotella oris-buccae group. Fusobacterium naviforme and Fusobacterium necrophorum were also susceptible to </=2 microgram of gemifloxacin per ml, while Fusobacterium varium strains exhibited a bimodal pattern; the other Fusobacterium species, such as Fusobacterium ulcerans and Fusobacterium russii, as well as Veillonella spp., the Prevotella melaninogenica group, Prevotella bivia, Clostridium difficile, and Bilophila wadsworthia were relatively resistant to gemifloxacin (MIC(90)s, >/=4 microgram/ml).

Anti-Infective Agents↗

Activities of telithromycin (HMR 3647, RU 66647) compared to those of erythromycin, azithromycin, clarithromycin, roxithromycin, and other antimicrobial agents against unusual anaerobes.

The comparative activity of telithromycin (HMR 3647) against 419 human anaerobic isolates was determined by the agar dilution method. At concentrations of </=0.5 microgram/ml, telithromycin was active against Actinomyces israelii, Actinomyces odontolyticus, Bacteroides tectum, Bacteroides ureolyticus, Bacteroides gracilis (now Campylobacter gracilis), Porphyromonas spp. (including Porphyromonas gingivalis and Porphyromonas macacae), Prevotella intermedia, Prevotella heparinolytica, and almost all Peptostreptococcus species. Clostridia showed species and strain variability, often with a biphasic pattern. Fusobacterium species, except Fusobacterium russii, were relatively resistant.

Anti-Bacterial Agents↗

Comparative in vitro activities of amoxicillin-clavulanate against aerobic and anaerobic bacteria isolated from antral puncture specimens from patients with sinusitis.

By an agar dilution method, the antimicrobial susceptibilities of antral sinus puncture isolates were studied. Pneumococci were generally susceptible to amoxicillin, azithromycin, and clarithromycin, but 17% of pneumococcal isolates were resistant to cefuroxime. Haemophilus influenzae isolates were resistant to amoxicillin and clarithromycin. beta-Lactamase production occurred in 69% of Prevotella species. One-third of Peptostreptococcus magnus isolates were resistant to azithromycin and clarithromycin. Cefuroxime had limited activity against Prevotella species and P. magnus. Levofloxacin was active against most isolates except peptostreptococci. Amoxicillin-clavulanate was active against all isolates, with the MIC at which 90% of the isolates were inhibited being < or = 1 microgram/ml.

Adult↗

Linezolid activity compared to those of selected macrolides and other agents against aerobic and anaerobic pathogens isolated from soft tissue bite infections in humans.

Linezolid was tested against 420 aerobes and anaerobes, including 148 Pasteurella isolates, by an agar dilution method. Linezolid was active against all Pasteurella multocida subsp. multocida and P. multocida subsp. septica isolates and most Pasteurella canis, Pasteurella dagmatis, and Pasteurella stomatis isolates. The MIC was </=2 microg/ml for staphylococci, streptococci, EF-4b, Weeksella zoohelcum, Fusobacterium nucleatum, other fusobacteria, Porphyromonas spp., Prevotella spp., peptostreptococci, and almost all Bacteroides tectum isolates.

Anti-Bacterial Agents↗

Activity of gatifloxacin compared to those of five other quinolones versus aerobic and anaerobic isolates from skin and soft tissue samples of human and animal bite wound infections.

The activity of gatifloxacin against 308 aerobes and 112 anaerobes isolated from bite wound infections was studied. Gatifloxacin was active at </=0.016 microg/ml against all 148 Pasteurella isolates (eight species and three subspecies) tested and all other aerobes tested, including Actinobacillus-Haemophilus spp., Eikenella corrodens, Neisseria weaveri, Weeksella zoohelcum, staphylococci, and streptococci. Fusobacteria were sometimes resistant. Gatifloxacin MICs at which 90% of the isolates were inhibited were 0. 125 microg/ml against Bacteroides tectum and Prevotella spp., 0.25 microg/ml against Porphyromonas spp., and 0.5 microg/ml against peptostreptococci.

Anti-Infective Agents↗

In vitro activity of gemifloxacin (SB 265805) against anaerobes.

Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 10(5) CFU/spot. Comparative antimicrobials tested included trovafloxacin, levofloxacin, grepafloxacin, sparfloxacin, sitafloxacin (DU-6859a), penicillin G, amoxicillin clavulanate, imipenem, cefoxitin, clindamycin, and metronidazole. The MIC(50) and MIC(90) (MICs at which 50 and 90% of the isolates were inhibited) of gemifloxacin against various organisms (with the number of strains tested in parentheses) were as follows (in micrograms per milliliter): for Bacteroides fragilis (28), 0.5 and 2; for Bacteroides thetaiotaomicron (24), 1 and 16; for Bacteroides caccae (12), 1 and 16; for Bacteroides distasonis (12), 8 and >16; for Bacteroides ovatus (12), 4 and >16; for Bacteroides stercoris (12), 0.5 and 0.5; for Bacteroides uniformis (12), 1 and 4; for Bacteroides vulgatus (11), 4 and 4; for Clostridium clostridioforme (15), 0.5 and 0.5; for Clostridium difficile (15), 1 and >16; for Clostridium innocuum (13), 0.125 and 2; for Clostridium perfringens (13), 0.06 and 0.06; for Clostridium ramosum (14), 0.25 and 8; for Fusobacterium nucleatum (12), 0.125 and 0.25; for Fusobacterium necrophorum (11), 0.25 and 0.5; for Fusobacterium varium (13), 0.5 and 1; for Fusobacterium spp. (12), 1 and 2; for Peptostreptococcus anaerobius (13), 0.06 and 0.06; for Peptostreptococcus asaccharolyticus (13), 0.125 and 0.125; for Peptostreptococcus magnus (14), 0.03 and 0.03; for Peptostreptococcus micros (12), 0.06 and 0.06; for Peptostreptococcus prevotii (14), 0.06 and 0.25; for Porphyromonas asaccharolytica (11), 0.125 and 0.125; for Prevotella bivia (10), 8 and 16; for Prevotella buccae (10), 2 and 2; for Prevotella intermedia (10), 0.5 and 0.5; and for Prevotella melaninogenica (11), 1 and 1. Gemifloxacin mesylate (SB 265805) was 1 to 4 dilutions more active than trovafloxacin against fusobacteria and peptostreptococci, and the two drugs were equivalent against clostridia and P. asaccharolytica. Gemifloxacin was equivalent to sitafloxacin (DU 6859a) against peptostreptococci, C. perfringens, and C. ramosum, and sitafloxacin was 2 to 3 dilutions more active against fusobacteria. Sparfloxacin, grepafloxacin, and levofloxacin were generally less active than gemifloxacin against all anaerobes.

Anti-Bacterial Agents↗

Novel bacterium isolated from a lung transplant patient with cystic fibrosis.

The major clinical problem for patients with cystic fibrosis (CF) is progressive loss of pulmonary function, usually due to chronic bacterial infections. A patient with CF and a lung transplant was severely infected with a previously unidentified gram-negative bacterium. We isolated this organism (strain DS15158) from the patient and characterized it by phylogenetic analysis of the small-subunit rRNA and biochemically by the BIOLOG GN MicroPlate assay, fatty acid analysis, and various standard laboratory tests. No close match to any other organism could be found. Isolate DS15158 represents a new genus-level divergence within the bacterial subdivision alpha-Proteobacteria on the basis of the 16S rRNA gene analysis.

Adult↗

Characterization of Bacteroides forsythus strains from cat and dog bite wounds in humans and comparison with monkey and human oral strains.

Bacteroides forsythus strains recovered from cat and dog bite wound infections in humans (n = 3), monkey oral strains (n = 3), and the human oral ATCC 43037 type strain were characterized by using phenotypic characteristics, enzymatic tests, whole cell fatty acid analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, PCR fingerprinting, and 16S rDNA (genes coding for rRNA) sequencing. All three bite wound isolates grew on brucella agar supplemented with 5% sheep blood, vitamin K1, and hemin. These strains, unlike the ATCC strain and previously described monkey oral and human clinical strains, did not require N-acetylmuramic acid supplementation for growth as pure cultures. However, their phenotypic characteristics, except for catalase production, were similar to those of previously identified strains. PCR fingerprinting analysis showed differences in band patterns from the ATCC strain. Also, SDS-PAGE and whole cell fatty acid analysis indicated that the dog and cat bite wound strains were similar but not identical to the human B. forsythus ATCC 43037 type strain and the monkey oral strains. The rDNA sequence analysis indicated that the three bite wound isolates had 99.93% homology with each other and 98.9 and 99.22% homology with the human ATCC 43037 and monkey oral strains, respectively. These results suggest that there are host-specific variations within each group.

Animals↗

Trovafloxacin compared with levofloxacin, ofloxacin, ciprofloxacin, azithromycin and clarithromycin against unusual aerobic and anaerobic human and animal bite-wound pathogens.

The activity of trovafloxacin and five other oral agents against 250 aerobic and 137 anaerobic strains isolated from human and animal bite wounds was determined by an agar dilution method. Trovafloxacin was active against all aerobic and fastidious facultative isolates at < or = 0.5 mg/L and all anaerobes at < or = 2 mg/L (Bacteroides tectum, Porphyromonas salivosa and Prevotella heparinolytica, < or = 0.25 mg/L; Porphyromonas spp., < or = 0.5 mg/L; Prevotella spp. and peptostreptococci, < or = 2.0 mg/L), except Fusobacterium nucleatum and other fusobacteria (MIC90 < or = 4 mg/L). Levofloxacin was generally one to two dilutions more active than ofloxacin, while ciprofloxacin was active against aerobes (MIC < or = 1 mg/L) but less active against anaerobic strains (MIC90 < or = 16 mg/L).

Animals↗

Activities of HMR 3004 (RU 64004) and HMR 3647 (RU 66647) compared to those of erythromycin, azithromycin, clarithromycin, roxithromycin, and eight other antimicrobial agents against unusual aerobic and anaerobic human and animal bite pathogens isolated from skin and soft tissue infections in humans.

The activities of HMR 3004 and HMR 3647 and comparator agents, especially macrolides, were determined by the agar dilution method against 262 aerobic and 120 anaerobic strains isolated from skin and soft tissue infections associated with human and animal bite wounds. HMR 3004 and HMR 3647 were active against almost all aerobic and fastidious facultative isolates (MIC at which 90% of the isolates are inhibited [MIC90], < or = 0.5 and 1 microg/ml, respectively) and against all anaerobes [Bacteroides tectum, Porphyromonas macacae (salivosa), Prevotella heparinolytica, Porphyromonas sp., Prevotella sp., and peptostreptococci] at < or = 0.25 and < or = 0.5 microg/ml, respectively, except Fusobacterium nucleatum (HMR 3004, MIC90 = 16 microg/ml; HMR 3647, MIC90 = 8 microg/ml) and other Fusobacterium species (MIC90, 1 and 2 microg/ml, respectively). In general, HMR 3004 and HMR 3647 were more active than any of the macrolides tested. Azithromycin was more active than clarithromycin against all Pasteurella species, including Pasteurella multocida subsp. multocida, Eikenella corrodens, and Fusobacterium species, while clarithromycin was more active than azithromycin against Corynebacterium species, Weeksella zoohelcum, B. tectum, and P. heparinolytica.

Animals↗

Evaluation of the RapID CB Plus system for identification of Corynebacterium species and other gram-positive rods.

Due to the difficulty of identifying Corynebacterium spp. with standard methods, we compared them with the RapID CB Plus system (Remel, Lenexa, Kans. [formerly Innovative Diagnostic Systems, Norcross, Ga.]), which consists of 4 carbohydrate and 14 preformed enzyme tests, for the identification of 98 clinical isolates of Corynebacterium sp., other coryneforms, Listeria monocytogenes, and 17 ATCC strains. Forty (95%) of 42 strains of Corynebacterium spp. were accurately identified to the species level by the RapID CB Plus system, and two additional strains of C. striatum were identified with one additional conventional test for lipid requirement. Twenty-seven (75%) of the 36 coryneform strains tested were identified correctly to the species level. However, three of four strains of Brevibacterium sp. and all seven of the L. monocytogenes strains were identified to the genus level only. Actinomyces strains had variable results, and the one strain of Arcanobacterium haemolyticum tested was not identified. Overall, the RapID CB Plus system compared favorably with the conventional methods, was easy to inoculate and interpret, and is promising as a new method for identification of gram-positive bacilli.

Actinomyces↗

Evaluation of a novel specimen transport system (Venturi Transystem) for anaerobic bacteria.

The Venturi Transystem (Copan Diagnostics, Corona, CA), with and without charcoal, is designed for transport of clinical specimens. It was evaluated for its ability to maintain the viability of pure cultures of selected anaerobic bacteria. Results indicated that the system supported survival of test strains within the time frame that most clinical specimens require to reach the clinical laboratory.

Bacteria, Anaerobic↗

Use of polymerase chain reaction fingerprinting to compare clinical isolates of Bacteroides fragilis and Bacteroides thetaiotaomicron from Germany and the United States.

Accurate identification of Bacteroides species is often problematic. Therefore, we used a polymerase chain reaction (PCR) fingerprinting technique with either a single nonspecific primer derived from tDNA intergenic spacer or a single primer that anneals to mini- and microsatellite DNA sequences to compare 34 clinical isolates of B. fragilis and 21 clinical isolates of B. thetaiotaomicron from Southern California with 32 clinical isolates of B. fragilis and 10 isolates of B. thetaiotaomicron from Germany. All German B. fragilis isolates (32 of 32) formed one PCR fingerprint group that matched the PCR profile of the B, fragilis reference strain ATCC (American Type Culture Collection) 25285, representative of DNA homology group I. In contrast, the isolates from Southern California formed two PCR fingerprint groups. Although most of these strains (29 of 34) also matched B. fragilis ATCC 25285, some strains (4 of 34) matched the DNA homology group II reference strain VPI (Virginia Polytechnic Institute) 2393. One of the 34 strains showed a unique profile. German B. thetaiotaomicron strains (10 of 10) formed one PCR fingerprint group, matching the reference strain B. thetaiotaomicron ATCC 29742, whereas the B. thetaiotaomicron isolates from Southern California showed heterogenous profiles.

Bacteroides↗

Bilophila wadsworthia clinical isolates compared by polymerase chain reaction fingerprinting.

Bilophila wadsworthia isolates recovered from a right-ear cholesteatoma and brain abscess of the same patient were analyzed by means of polymerase chain reaction (PCR) fingerprinting with single primers (T3B and M13 core) to ascertain if they originated from the same clone. Their PCR fingerprint profiles were compared with those of three additional B. wadsworthia clinical isolates and the type strain (ATCC 49260). The two isolates from the same patient produced PCR fingerprint profiles identical to each other, regardless of which primer was used. All isolates' PCR fingerprint profiles, with use of either the T3B or M13 core primer, shared some major and minor bands. However, differences in additional major and minor bands distinguished each of the additional isolates, suggesting that there are different subgroups of B. wadsworthia.

Brain Abscess↗