Effect of copper on the antifungal activity of disulfiram (Antabuse®) in fluconazole-resistant Candida strains.

Unlabelled: Disulfiram (Antabuse®) is an alcohol use disorder medication that exhibits antifungal activity against Candida species. The purpose of this investigation was to determine if copper potentiates the antifungal effects of disulfiram based on prior observations that the combination demonstrates increased antitumor activity. Our findings revealed that copper addition conferred up to an eight-fold reduction in the minimum inhibitory concentrations (MICs) of disulfiram by broth microdilution assessment.

Ambiguity in the identification of Streptococcus pneumoniae. Optochin, bile solubility, quellung, and the AccuProbe DNA probe tests.

We prospectively evaluated 639 sequential clinical isolates of alpha-hemolytic gram-positive cocci as possible Streptococcus pneumoniae. On the basis of results of tests for optochin susceptibility, tube bile solubility, and the quellung reaction, 74 strains (11.6%) were categorized as unequivocal pneumococci (optochin positive, tube bile solubility positive, quellung reaction positive).

User interface reengineering. Innovative applications of bar coding in a clinical microbiology laboratory.

Some clinical laboratory departments (such as microbiology) provide extensive reporting of text and other data not generated by instruments that can be interfaced to a laboratory information system. These data are usually entered into the laboratory information system manually by keyboard data entry, which can be cumbersome and time consuming. Bar codes, which are already used in laboratories to facilitate rapid entry of sample-identifying information, have the potential to be used much more broadly as a generalizable data entry technique.

Laboratory detection of Clostridium difficile. A comparison of media and incubation systems.

Parallel testing for culture recovery of Clostridium difficile was performed using three selective media in each of four anaerobic incubation environmental systems. Testing was completed on 67 stool samples from 60 hospitalized patients in whom C difficile-associated diarrhea was suspected. Three different media were evaluated: CCFA (modified cycloserine-cefoxitin-fructose agar), CCFA-PRAS (CCFA, prereduced-anaerobically-sterilized) and CMBA (modified cycloserine-mannitol-blood agar).

Ten years of prospective Clostridium difficile-associated disease surveillance and treatment at the Minneapolis VA Medical Center, 1982-1991.

Objectives: To understand the epidemiology, risks, and management of Clostridium difficile-associated disease (CDAD) and to establish and evaluate reliable methods of surveillance.

Design: Case finding was done by daily ward and laboratory rounds. The criteria for CDAD diagnosis were: at least four unformed stools per day for 2 days and a positive culture or cytotoxin for C difficile, or positive endoscopy or autopsy for pseudomembranes.

Bactericidal action of gentamicin against enterococci that are sensitive, or exhibit low- or high-level resistance to gentamicin.

Treatment of serious enterococcal infection involves the use of penicillin-aminoglycoside combination therapy if the aminoglycoside minimum inhibitory concentration (MIC) is < or = 2000 micrograms/ml, and the organism is susceptible to penicillin or ampicillin. We evaluated killing of 15 enterococci that differ in their susceptibility to gentamicin using time-kill studies at different gentamicin concentrations. Sensitive strains had a uniform population killed by gentamicin concentrations equal to or above the MIC.

Activity of twenty-one antimicrobial agents including l-ofloxacin against quinolone-sensitive and -resistant, and methicillin-sensitive and -resistant Staphylococcus aureus.

There is a need to identify alternative agents to vancomycin for the treatment of infections with methicillin-resistant Staphylococcus aureus (MRSA). One candidate is the l isomer of ofloxacin (DR-3355). We tested 520 frozen MRSA isolates, 248 fresh MRSA isolates, and 375 fresh methicillin-susceptible S.

Utility of slide centrifuge gram's stain versus quantitative culture for diagnosis of urinary tract infection.

The slide centrifuge (cytospin) Gram's-stain technique has been shown in previous studies to be a sensitive technique for detecting bacteriuria when compared to culture. The method concentrates urine sediment in a small defined area on a glass slide for Gram's staining. A positive test provides morphologic information about suspected pathogens.

Tests for bactericidal effects of antimicrobial agents: technical performance and clinical relevance.

Bactericidal testing has been used for several decades as a guide for antimicrobial therapy of serious infections. Such testing is most frequently performed when bactericidal antimicrobial agent therapy is considered necessary (such as when treating infectious endocarditis or infection in an immunocompromised host). It has also been used to ensure that the infecting organism is killed by (not tolerant to) usually bactericidal compounds.

Comparison of the VIDAS Clostridium difficile toxin A immunoassay with C. difficile culture and cytotoxin and latex tests.

The VIDAS Clostridium difficile toxin A immunoassay (CDA) is a new, automated, enzyme-linked fluorescent-antibody assay for detection of C. difficile toxin A antigen in stool specimens. Simultaneous, parallel testing was performed by using the VIDAS CDA, the Culturette brand CDT latex test for C.

The slide centrifuge gram stain as a urine screening method.

A slide centrifuge Gram stain procedure was performed to screen for bacteriuria 4161 urine specimens submitted in urine preservative tubes for routine culture. For slide centrifuge Gram staining, each urine sample was mixed well. Thereafter, 0.

An evaluation of three commercial fecal transport systems for the recovery of enteric pathogens.

Twenty-five isolates, including six strains of Shigella species, six strains of Salmonella species, five strains of Yersinia enterocolitica, six strains of Campylobacter jejuni, and two strains of Vibrio parahaemolyticus, were inoculated at a concentration of 1.5 x 10(4) colony-forming units/mL into the following transport systems: Fekal Enteric Plus (Trend Scientific, Inc., St.

Aminoglycoside resistance and aminoglycoside usage: ten years of experience in one hospital.

For 10 years the 700-bed Minneapolis Veterans Affairs Medical Center has conducted a policy of carefully controlled aminoglycoside usage and monitoring of resistance of over 25,000 aerobic and facultative gram-negative bacillary isolates to the aminoglycosides. On two occasions during the 1980s, our experience of introducing amikacin at a high level of usage was associated with a significant reduction in resistance to gentamicin and tobramycin among gram-negative bacilli. Rapid reintroduction of gentamicin usage in 1982 after the first amikacin period was associated with a significant and rapid increase in gentamicin and tobramycin resistance.

Comparison of traditional gas chromatography (GC), headspace GC, and the microbial identification library GC system for the identification of Clostridium difficile.

Three gas chromatography (GC) methods were compared for the identification of 52 clinical Clostridium difficile isolates, as well as 17 non-C. difficile Clostridium isolates. Headspace GC and Microbial Identification System (MIS) GC, an automated system which utilizes a software library developed at the Virginia Polytechnic Institute to identify organisms based on the fatty acids extracted from the bacterial cell wall, were compared against the reference method of traditional GC.

Emergence of ciprofloxacin resistance in nosocomial methicillin-resistant Staphylococcus aureus isolates. Resistance during ciprofloxacin plus rifampin therapy for methicillin-resistant S aureus colonization.

We initiated a randomized, single-blinded trial of ciprofloxacin plus rifampin vs sulfamethoxazole and trimethoprim plus rifampin in the therapy for patients who underwent colonization with methicillin-resistant Staphylococcus aureus (MRSA). Patients who were colonized with MRSA received 2 weeks of either regimen. The study was terminated after the enrollment of 21 subjects due to the recognition of ciprofloxacin resistance in 10 of 21 new MRSA isolates during the last 2 months of the study.

Results of a prospective, 18-month clinical evaluation of culture, cytotoxin testing, and culturette brand (CDT) latex testing in the diagnosis of Clostridium difficile-associated diarrhea.

An 18-mo evaluation of culture, cytotoxin, and latex testing for Clostridium difficile was performed between July 1, 1985, and December 31, 1986, on 1,536 specimens from 1,406 patients during evaluation of diarrhea. All cases with at least one test positive were investigated for clinical status. There were 144 Clostridium difficile-associated diarrhea (CAD) patients; 139 (97%) were positive by culture, 96 (67%) by cytotoxin, and 98 (68%) by latex testing.

Using the microbiology laboratory in the diagnosis of pneumonia.

Pneumonia/influenza is one of the top ten leading causes of mortality in the United States each year. The identification of the etiologic agent responsible for lower respiratory tract infection plays an important role in the proper management of this clinical problem. The specimens submitted for evaluation are obtained in diverse ways and include expectorated sputum, material from transtracheal and bronchoscopic procedures, pleural fluid and lung aspirates, and biopsy of actual lung tissue.

Selenomonas bacteraemia--case report and review of the literature.

Selenomonas species are crescent shaped Gram-negative bacilli with a characteristic tuft of flagella located on the concave surface. They are normally found in human gingiva or the rumen of herbivores. The first case of Selenomonas bacteraemia to be reported in a patient immunocompromised by malignant disease is described and the two previously reported cases of Selenomonas bacteraemia as reviewed.

Laboratory quality assurance testing of microbiologic media from commercial sources.

Culture media that perform as intended are crucial to accurate work by a clinical microbiology laboratory. As cost-containment becomes an increasingly important pressure in clinical laboratory management, the value of each laboratory performing its own quality assurance testing of media has been challenged if the media are purchased from a manufacturer who is required to perform quality assurance testing. In the past ten years of using commercially prepared media from eight different national and regional suppliers, the authors have encountered an average of six types (15 shipments) of media each year that failed to meet their laboratory's performance criteria, which reinforces the need for clinical laboratories to continue their own performance testing of media manufactured commercially, particularly when the media are used for primary isolation.

Occurrence and reproducibility of the "skip" phenomenon in bactericidal testing of Staphylococcus aureus.

A "skip" phenomenon, in which subcultures to determine bactericidal endpoints show discordant results, can make bactericidal testing of Staphylococcus aureus difficult to interpret. Either a single or several consecutive concentrations may be skipped, with insignificant growth from these concentrations, but heavy growth from higher antimicrobic concentrations. Replicate macrodilution minimum bactericidal concentration testing of cephalothin against S.

Pseudomonas infection of the biliary system resulting from use of a contaminated endoscope.

Pseudomonas aeruginosa was present in bile cultures from 10 patients who had undergone previous endoscopic retrograde cholangiopancreatography in 1984. After environmental cultures and review of instrument disinfection, we traced the infections to a single endoscope contaminated with P. aeruginosa, serotype 10.

In vitro activity of efrotomycin, ciprofloxacin, and six other antimicrobials against Clostridium difficile.

The susceptibility of 69 clinical isolates of Clostridium difficile from the Minneapolis Veterans Administration Medical Center and 29 C. difficile strains from other hospitals to efrotomycin, ciprofloxacin, and six other antimicrobials was tested in vitro by agar dilution. Ciprofloxin (MIC50 and MIC90 = 8 mcg/ml) was only moderately active whereas efrotomycin (MIC50 = 0.

Detection of Clostridium difficile toxins A (enterotoxin) and B (cytotoxin) in clinical specimens. Evaluation of a latex agglutination test.

A new latex test, Culturette Brand Rapid Latex Test for detection of Clostridium difficile toxin A, was tested on 408 stool samples. In 247 frozen tissue culture supernate specimens previously obtained from patients with C. difficile-associated diarrhea (CAD), the latex test (enterotoxin) was positive in 182 (74%) as compared with 194 (79%) for the repeat tissue culture (P greater than 0.

False susceptible penicillin G MICs for Streptococcus pneumoniae with a commercial microdilution system.

A commercial minimal inhibitory concentration (MIC) panel that contains a broth of undisclosed formulation intended to support growth of streptococci unable to grow in Mueller-Hinton broth was found to give false susceptible MIC results for pneumococci. The authors encountered several Streptococcus pneumoniae isolates that showed resistance by the oxacillin disk diffusion test, but showed a susceptible penicillin G MIC when tested in an unsupplemented MIC panel. Seven isolates that showed penicillin G resistance by oxacillin disk diffusion testing were retested for penicillin G susceptibility with oxacillin disk diffusion, commercial MIC panels, Mueller-Hinton with blood agar dilution, and Mueller-Hinton with blood broth microdilution.