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E J Goldstein

Publications and source records attributed to E J Goldstein.

At least 73 records · Page 4Linked to original sources

Selected nonsurgical anaerobic infections: therapeutic choices and the effective armamentarium.

Anaerobic bacteria play an important role in diverse clinical infections. In this review the historical role and prevalence of anaerobes and their potential impact on the management of patients are discussed in terms of pleuropulmonary infections, animal and human bite-wound infections, diabetic foot infections, bacteremia, tetanus, diarrhea due to Anaerobiospirillum succiniciproducens, and diarrhea due to toxigenic Bacteroides fragilis.

Bacteremia↗

Characterization of a beta-lactamase from Clostridium clostridioforme.

A beta-lactamase-producing strain of Clostridium clostridioforme isolated from human peritoneal fluid was examined by MIC testing and enzyme characterization. MICs of penicillins (64-512 mg/L) were higher than those of cephalosporins (8-128 mg/L); the strain was susceptible to cefoxitin (8 mg/L) and imipenem (1 mg/L). No enhancement of cephalosporin activity occurred when clavulanate was also added, but a limited degree of enhancement of penicillin activity (resulting in beta-lactam MICs higher than available NCCLS breakpoints) occurred when clavulanate, sulbactam or tazobactam was added simultaneously. By contrast, addition of BRL 42715 with amoxycillin, ticarcillin or piperacillin led to a drop in beta-lactam MICs from 512 to < or = 1 mg/L, with a drop from 64 to 1 mg/L when BRL 42715 was added with cefotaxime. All inhibitors were added at fixed concentrations of 2 mg/L. As determined spectrophotometrically, the enzyme hydrolysed penicillin G, cloxacillin and piperacillin (Vmax values (%) 372, 1816, 1001, respectively relative to cephaloridine) more efficiently than cephalosporins (69-191, with cephaloridine as 100%). Km values (microM) varied between 30-308 microM (penicillins) and 2-20 microM (cephalosporins). Relative enzyme efficiency (relative Vmax/Km with cephaloridine as 100) varied from 21-100 (cephalosporins) and 8-77 (penicillins). IC50 values (microM) with nitrocefin, piperacillin and penicillin G substrates (concentrations 20, 100 and 20 microM, respectively) were > 1000, 7, 3.5 (clavulanate); > 1000, 300, 59 (sulbactam), > 1000, 29, 7.7 (tazobactam); 0.0004, 0.001, 0.0018 (BRL 42715). The enzyme was not inhibited by EDTA, cefoxitin, cloxacillin or aztreonam, but was inhibited by pCMB.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗

Common bacterial skin infections. Diagnostic clues and therapeutic options.

Prompt, accurate characterization of skin infections can help avoid serious, more invasive complications. With appropriate empirical therapy, treatment failure can be prevented. The authors of this article discuss several common skin infections, including bite wound infections, and recommend various drug regimens to consider when planning initial therapy.

Anti-Bacterial Agents↗

Empyema due to Bacteroides gracilis: case report and in vitro susceptibilities to eight antimicrobial agents.

We describe a patient with empyema due to Bacteroides gracilis and a viridans streptococcus. Therapy with both cefoxitin and imipenem failed, and the patient remained symptomatic even after thoracotomy was performed. Clinical response occurred after initiation of clindamycin therapy. The susceptibilities of the patient's isolate, other clinical strains, and the reference strain were determined by an agar dilution method. The isolates were generally susceptible to all the agents tested; however, some strains were resistant to clindamycin (MIC, 8 micrograms/mL), penicillin G (MIC90, 16 micrograms/mL), and metronidazole (MIC90, 64 micrograms/mL). The B. gracilis isolate from our patient was susceptible to all agents tested, including cefoxitin and imipenem.

Adult↗

Incidence and clinical significance of anaerobic bacteremia in a community hospital.

The importance of performing anaerobic blood cultures on a routine basis has been questioned in recent reports; this prompted us to review data on episodes of anaerobic bacteremia that have occurred in our 350-bed community hospital. In 1991, 771 of 7,397 blood cultures yielded bacteria or fungi; 569 (7.7%) were true positive cultures, 35 (6.2%) of which yielded 48 anaerobic isolates from 20 patients. The charts of these patients were reviewed, and it was determined that 16 of the patients had significant anaerobic bacteremia. The outcome was fatal for seven (44%) of these 16 patients, including two who died before results were reported. The results of blood culture led to a change of antimicrobial therapy for nine (56%) of the 16 patients. The source of infection was obvious for 11 of the 16 patients, and 50% of patients were receiving antimicrobial agents active against anaerobes before culture results were obtained. Although anaerobic bacteremia is uncommon in our hospital, positive culture results often resulted in a change in antimicrobial therapy.

Adult↗

Patterns of susceptibility to fluoroquinolones among anaerobic bacterial isolates in the United States.

The activity of the fluoroquinolone antibiotics against anaerobic bacteria has generally been moderate to poor. Nalidixic acid and cinoxacin show poor activity against almost all anaerobes. Norfloxacin and enoxacin exhibit poor anaerobic activity (MIC90, 8- > 256 micrograms/mL) except against Clostridium perfringens, Bacteroides ureolyticus, and some eubacteria. Norfloxacin is slightly more active than enoxacin against some Bacteroides species. While ciprofloxacin is more active than earlier fluoroquinolones against anaerobes such as Bacteroides fragilis (MIC90, 4-16 micrograms/mL), fusobacteria, and peptostreptococci, its activity is often variable and its MIC90 is frequently close to the maximal level attainable in serum. Ofloxacin is active against B. fragilis (MIC90, 4-8 micrograms/mL) but not against other species of the B. fragilis group (MIC90, 8-32 micrograms/mL); other anaerobes (e.g., peptostreptococci and fusobacteria) are generally susceptible to < or = 8 micrograms of ofloxacin/mL. Several newer quinolones exhibit improved anaerobic activity (although the studies yielding relevant data have often used diverse methods, small numbers and varieties of isolates, and different breakpoints). CI-960 and WIN 57273 inhibit 95% of strains tested at < or = 2 micrograms/mL. CI-990, sparfloxacin, and temafloxacin inhibit most anaerobes at < or = 2 micrograms/mL, but clustering around the breakpoint and strain variability have been noted. CI-990 is active against more than 85% of B. fragilis strains (MIC90, 4 micrograms/mL), but other species of the B. fragilis group often require > 4 micrograms/mL for inhibition; Prevotella bivia, Fusobacterium varium, and Fusobacterium ulcerans are usually resistant.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Infective Agents↗

Comparative susceptibility of the Bacteroides fragilis group species and other anaerobic bacteria to meropenem, imipenem, piperacillin, cefoxitin, ampicillin/sulbactam, clindamycin and metronidazole.

The in-vitro activity of meropenem, imipenem, piperacillin, cefoxitin, ampicillin/sulbactam, clindamycin and metronidazole was determined against 395 strains of strict and facultative anaerobes, including Gardnerella vaginalis, Lactobacillus spp. and Mobiluncus spp. The activities of meropenem and imipenem were within one dilution of their MIC50 and MIC90 values. One isolate of Bacteroides fragilis, two of Bacteroides distasonis, and two of Bacteroides ovatus showed resistance or diminished susceptibility to meropenem and imipenem. Metronidazole was active against almost all obligate anaerobic isolates. Some non-spore-forming Gram-positive bacilli and lactobacilli were resistant. Ampicillin/sulbactam inhibited almost all isolates at < or = 16/8 mg/L. The activity of clindamycin and cefoxitin was relatively good, but some strains of non-fragilis B. fragilis group species were resistant. Piperacillin was the least active agent tested.

Ampicillin↗

Comparative susceptibilities of 173 aerobic and anaerobic bite wound isolates to sparfloxacin, temafloxacin, clarithromycin, and older agents.

The in vitro activities of sparfloxacin, temafloxacin, ciprofloxacin, ofloxacin, clarithromycin, erythromycin, tetracycline, cephalothin, penicillin G, and amoxicillin-clavulanic acid against 173 recent clinical bite wound isolates were determined by agar dilution. Sparfloxacin was active against all strains (MIC for 90% of strains tested, < or = 1 micrograms/ml) except for most fusobacteria and one-third of the Prevotella spp. The other fluoroquinolones had similar activities but higher MICs, especially for streptococci. Clarithromycin was more active against many isolates including Pasteurella multocida than erythromycin, with MICs of < or = 2 micrograms/ml (versus 4 micrograms/ml for erythromycin).

Animals↗

Bite wounds and infection.

One of every two Americans will be bitten by an animal or by another person at some point. Bites account for approximately 1% of all visits to emergency rooms; injuries inflicted by dogs are most common. The bacteria involved in infection of bite wounds include Pasteurella multocida, Staphylococcus aureus, Staphylococcus intermedius, alpha-hemolytic streptococci, Capnocytophaga canimorsus, and other members of the oral flora. Anaerobic bacteria are present in approximately one-third of bite wounds and are associated with the formation of abscesses and with relatively serious infections. P. multocida is found in infections of cat bites more than 50% of the time. The bacteriology of bite wounds inflicted by exotic animals reflects the animals' oral flora. Bites inflicted by humans are often more serious than those inflicted by animals. Infections of human bites are associated with alpha-hemolytic streptococci, S. aureus, Eikenella corrodens, Haemophilus species, and (in more than 50% of cases) anaerobic bacteria. The principles of management of bite wounds are discussed.

Animals↗

Comparative activity of ciprofloxacin, ofloxacin, sparfloxacin, temafloxacin, CI-960, CI-990, and WIN 57273 against anaerobic bacteria.

The in vitro activities of seven fluoroquinolones against 290 anaerobes were determined by agar dilution. CI-960 and WIN 57273 inhibited greater than 95% of the strains at less than or equal to 2 micrograms/ml. CI-990 required less than or equal to 16 micrograms/ml. Clustering around 2 to 4 micrograms/ml was noted for Bacteroides fragilis group organisms with CI-990, sparfloxacin, and temafloxacin. Temafloxacin and sparfloxacin inhibited most strains at less than or equal to 2 micrograms/ml. B. fragilis was more susceptible to all quinolones than were the other B. fragilis group strains.

Anti-Infective Agents↗

National hospital survey of anaerobic culture and susceptibility testing methods: results and recommendations for improvement.

The methods for performing anaerobic bacterial isolation and identification continue to change and improve. Anaerobic susceptibility testing has become controversial, and method-dependent variability has been noted. To assess the status of clinical anaerobic bacteriology in the United States, we surveyed, by means of a questionnaire, 120 hospitals, selected at random, with bed capacities of 200 to 1,000, and we received responses from 88 (73%). All hospitals performed cultures for anaerobes. The media and methods used for transport, initial processing, incubation, and identification varies between the different regions in the United States. Thirty percent of laboratories did not perform susceptibility studies, 16% used a reference laboratory, and 54% performed them in house. For half the laboratories, susceptibility testing was performed on isolates depending on the source; in this case, blood cultures were tested by 97% of the laboratories, serious infections were tested by 60%, sterile body sites were tested by 73%, pure cultures were tested by 47%, and tests were done by physician request by 39%. For laboratories doing testing, the broth disk method, no longer sanctioned by the National Committee for Clinical Laboratory Standards, was used most often (56%), followed by microdilution (33%), beta-lactamase testing (25%), macrotube dilution (2%), and agar dilution (2%). The antimicrobial agents tested were as follows: penicillin-ampicillin, 94%; clindamycin, 94%, metronidazole, 90%; chloramphenicol, 80%; cefoxitin, 76%; tetracyclines, 51%; and erythromycin, 45%. All other agents were tested by less than or equal to 25% of laboratories; the methods used could be improved to make the results more timely and consequently more clinically relevant.

Bacteria, Anaerobic↗

Escherichia coli resistant to ampicillin/sulbactam.

Escherichia coli strains resistant to ampicillin/sulbactam from hospitals in 4 different geographic locations were examined with respect to type and amount of beta-lactamase produced. A total of 5 strains was examined from each region. The isoelectric points of all of the involved beta-lactamases were 5.4, corresponding to TEM-1. Km and Vmax values of the beta-lactamases among the clinical isolates resembled those from the control TEM-1 strain. In an 18-hour broth culture the highly resistant isolates produced 3 times more beta-lactamase as compared to the ampicillin/sulbactam-susceptible isolates. However, the highly resistant strains contained approximately the same amount of plasmid DNA (size of > 6,500 bp) as the susceptible isolates. In transformation experiments, both the resistance and the degree of resistance appeared to have been transferable by plasmids. The mechanism for resistance is likely to be a baseline overproduction of TEM-1 beta-lactamase due to either an alteration in the control of gene expression or simply to an increase in the number of copies of the beta-lactamase gene in the plasmids.

Ampicillin↗

Antibacterial activity of crotalid venoms against oral snake flora and other clinical bacteria.

Despite heavy oral and fang contamination of crotalid species with a wide variety of potentially pathogenic bacteria, crotalid envenomation is associated with a low incidence of bacterial infection. Minimal inhibitory and bactericidal concentrations of venoms from three crotalid species were determined against six aerobic and eight anaerobic reference and oral crotalid microorganisms. All anaerobic isolates were resistant to greater than 20,480 micrograms/ml, whereas variable activity (range, 5-20,480 micrograms/ml) was observed for aerobic strains. Further studies against other aerobic clinical isolates demonstrated that venom had the greatest activity (MIC, less than or equal to 80 micrograms/ml) against staphylococci, Pseudomonas aeruginosa, and Enterobacter, Citrobacter, Proteus, and Morganella species. Inhibitory activity was lost with prolonged incubation for many gram-negative species. Crotalid venoms are broadly active against aerobic gram-negative and -positive bacteria. This activity may play a role in the low incidence of infection after envenomation injuries.

Animals↗

A selective medium for Fusobacterium spp.

A new selective medium (JVN) for the isolation of Fusobacterium spp. from clinical material is described. The medium incorporates josamycin, vancomycin and norfloxacin (at 3, 4 and 1 microgram/ml, respectively) as the selective agents, plus 5% defibrinated horse blood in Fastidious Anaerobe Agar Base (Lab M). This formula allowed luxuriant growth of all 82 strains (eight recognized species) of fusobacteria tested, while significantly inhibiting 51/51 (100%) strains of facultative anaerobes and 45/51 (88%) strains of other obligate anaerobes. JVN medium allowed the successful isolation of strains of Fusobacterium naviforme, F. nucleatum and F. necrophorum from the gingivae of 9/16 healthy volunteers, and strains of F. varium and F. mortiferum from faecal suspensions seeded with these organisms.

Culture Media↗

Susceptibility of anaerobic bacteria isolated from intra-abdominal infections to ofloxacin and interaction of ofloxacin with metronidazole.

The in vitro activities of ofloxacin alone and in combination with metronidazole against 177 anaerobic bacteria isolated from intra-abdominal infections, as determined by broth microdilution, showed that some Bacteroides fragilis strains were susceptible and that most other B. fragilis group species strains were resistant to ofloxacin. Isolates of other anaerobic species and genera, including those causing female genital tract disease, were generally susceptible to ofloxacin. Ofloxacin in combination with metronidazole usually showed an additive or indifferent interaction but no antagonism.

Abdomen↗