Search PubMed⌕ Search

Biomedical subjects

S Shadomy

Publications and source records attributed to S Shadomy.

At least 37 records · Page 2Linked to original sources

Exoantigen test for differentiation of Exophiala jeanselmei and Wangiella dermatitidis isolates from other dematiaceous fungi.

Concentrated (25X) exoantigens of 105 isolates of pathogenic and saprophytic dematiaceous fungi and 3 isolates of Sporothrix schenckii were analyzed by the microimmunodiffusion method. The reagents used were nonadsorbed and adsorbed sera produced in New Zealand rabbits. One set of rabbits was immunized with soluble antigens of a 1-month-old culture of Exophiala jeanselmei (ATCC 34123), and the other set was immunized with soluble antigens from a culture of Wangiella dermatitidis (ATCC 28869). The reference antigens were 25X-concentrated exoantigens of the above cultures. This exoantigen test permitted the differentiation of E. jeanselmei and W. dermatitidis from one another as well as from other Exophiala species, Fonsecaea species, Phialophora species, Cladosporium species, Rhinocladiella species, and Sporothrix schenckii by presence or absence of lines of identity or of partial identity, or lines of nonidentity. Using adsorbed serum eliminated the problems with cross-reactivity seen with nonadsorbed serum. Thus, with an adsorbed serum as the reagent, it was possible to presumptively differentiate E. jeanselmei and W. dermatitidis from one another and from other dematiaceous fungi.

Antigens, Fungal↗

In vitro susceptibility studies with oxiconazole (Ro 13-8996).

Oxiconazole (Ro 13-8996) is a recently described imidazole derivative intended for topical use. 128 isolates of pathogenic fungi were tested in vitro against oxiconazole, miconazole, and ketoconazole using an agar dilution method. Results indicated that miconazole was markedly more active than either oxiconazole or ketoconazole against Candida albicans while ketoconazole was the more active compound against Candida parapsilosis. A species specific difference in the susceptibilities of isolates of Aspergillus fumigatus and Aspergillus flavus to all three imidazoles with A. flavus being more susceptible was noted. Both Mucor and Rhizopus were more susceptible to oxiconazole than to either miconazole or ketoconazole. There were no noticeable differences among the dermatophytes in tests with the three drugs with all geometric mean minimum inhibition concentrations (MIC) being less than 1.0 micromilligram-1. The dematiaceous fungi also demonstrated no major differences in susceptibility to the three drugs. One isolate of Pseudallescheria boydii was relatively resistant to all three drugs (MIC greater than or equal to 16 micromilligrams-1).

Antifungal Agents↗

In vitro antibacterial activity of norfloxacin compared with eight other antimicrobial agents.

The antibacterial activity of norfloxacin, an organic acid structurally related to nalidixic acid, was compared with that of the oral cephalosporins cefaclor and cephalexin, and with that of nalidixic acid, cinoxacin, amikacin, ampicillin, trimethoprim alone and the combination of trimethoprim and sulfamethoxazole. Agar dilution studies were performed with a total of 398 clinical isolates of gram-negative bacteria. Norfloxacin was found to be the most active drug studied against each of the different groups of organisms tested. MIC90 values for norfloxacin were as follows: Citrobacter spp., 2 micrograms/ml; Enterobacter spp., 0.13 micrograms/ml; Escherichia coli, 0.06 micrograms/ml; Klebsiella spp., 0.13 micrograms/ml; Proteus spp., 0.06 micrograms/ml; Salmonella spp., 1 microgram/ml; Serratia spp., 0.13 micrograms/ml; and Pseudomonas spp., 2 micrograms/ml. MIC90 values for the other drugs were 4 micrograms/ml or greater and many organisms were totally resistant to one or more of the other drugs (MIC greater than 128 micrograms/ml). Cross resistance between norfloxacin and the related drugs nalidixic acid and cinoxacin was not observed.

Anti-Bacterial Agents↗

Disk diffusion susceptibility tests with norfloxacin: confirmation of proposed interpretive criteria.

One hundred and eighty three clinical isolates of aerobic bacteria were tested against norfloxacin by both agar dilution (WHO-ICS) and disk diffusion test procedures (standardized FDA single disk test). Two experimental 10 microgram norfloxacin disks were studied. Results were analyzed in terms of recently recommended breakpoints for clinical susceptibility (MIC less than or equal to 16 micrograms/ml, zone diameter greater than or equal to 17 mm) and resistance (MIC greater than or equal to 32 micrograms/ml, zone diameter less than or equal to 12 mm). Excellent correlation was demonstrated by statistical analysis between paired MIC and zone size values (average value for each MIC; r = -0.9782). An MIC of 16 micrograms/ml was found to correlate with a zone of 10.4 mm. Application of the recommended zone size breakpoints resulted in prediction of 177 isolates as being susceptible while six (3.3%) were predicted to be either intermediate or resistant. The findings of this study validate the earlier recommendations stated above.

Aerobiosis↗

In-vitro inhibitory activities of 2 new orally absorbable imidazole derivatives: BAY n 7133 and BAY 1 9139.

The inhibitory activities of 2 new orally absorbed antifungal imidazole derivatives, BAY n 7133 and BAY 1 9139, were compared in vitro with those of ketoconazole and miconazole. Clinical isolates of pathogenic fungi tested included 35 yeasts, 62 dimorphic fungal pathogens, 37 filamentous fungi and 31 dermatophytes. LY 121019, a semisynthetic analog of echinocandin B, was included in tests with the pathogenic yeasts. Both BAY n 7133 and BAY 1 9139 were found to be broad spectrum antifungal agents. The spectra of these newer compounds were comparable to those of ketoconazole and miconazole; however only BAY n 7133 resembled these latter 2 imidazoles quantitatively in terms of the degree of antifungal activity as indicated by measurable MICs. In contrast, the spectrum of LY 121019 appeared to be confirmed only to isolates of Candida.

Antifungal Agents↗

Treatment of systemic mycoses with ketoconazole: emphasis on toxicity and clinical response in 52 patients. National Institute of Allergy and Infectious Diseases collaborative antifungal study.

The pharmacology, in vitro mycologic activity, toxicity, and efficacy of ketoconazole were studied in a Phase-II evaluation by the National Institutes of Health and National Institute of Allergy and Infectious Disease Mycoses Study Group. This report emphasizes the toxicity and clinical response data in 52 patients with the following systemic mycoses: blastomycosis in 16 patients; nonmeningeal coccidioidomycosis in 13; histoplasmosis in 8; nonmeningeal cryptococcosis in 7; sporotrichosis in 7; and both blastomycosis and nonmeningeal coccidioidomycosis in 1. Maximum daily doses of ketoconazole were 100 mg in 1 patient; 200 mg in 23; 400 mg in 12; and 600 mg in 16. In 52% of the patients, duration of therapy ranged from less than 1 to 6 months, whereas in 35%, duration ranged from 7 to 12 months, and in 13%, from 12 to 22 months. In 35 patients (67%), evidence of toxicity was not seen. Nausea, anorexia, or vomiting occurred in 21%. Cure or marked improvement was shown in 27 patients (52%), whereas failure of the primary course was seen in 14 (27%) and relapse after ketoconazole was discontinued in 11 (21%). Although this evaluation did not provide clear-cut clinical response data, our results indicate that ketoconazole, in the dosage regimens used, was more effective in patients with histoplasmosis and nonmeningeal cryptococcosis than in patients with blastomycosis and nonmeningeal coccidioidomycosis, and least effective in patients with sporotrichosis.

Adolescent↗

Cryptococcal meningitis in pregnancy.

Cryptococcal meningitis was diagnosed in a pregnant woman at 21 weeks' gestation. The availability of fetal tissues, blood, and amniotic fluid in such a patient receiving therapy with amphotericin B plus flucytosine afforded the opportunity to study the effects of the disease and therapeutic agents on the developing fetus. The amphotericin B concentration in amniotic fluid was 0.25 micrograms/ml and that of flucytosine was 168 micrograms/ml. The concentrations in cord blood were 0.3 micrograms/ml and 64.7 micrograms/ml, respectively. No evidence was found of amphotericin B or flucytosine toxicity in fetal tissues, although exposure of the fetus to these compounds was of brief duration.

Adult↗

Near-drowning complicated by brain abscess due to Petriellidium boydii.

Extracutaneous infection from Petriellidium boydii is an unusual occurrence despite the ubiquity of the organism in nature. Central nervous system infection by this organism is extremely rare, only seven previous reports having been found. The rarity of this manifestation prompted the report of a brain abscess occurring in a previously healthy youth after a near-drowning. The source of the infection was likely to have been the river water at the accident site, from which P boydii was isolated. Although previous in vitro susceptibility data and failure of amphotericin B therapy in a similar infection suggested miconazole treatment might be beneficial, the organism causing the brain abscess was resistant to miconazole and amphotericin B. This report emphasizes the urgent need for safer and more predictably effective alternatives to currently available antifungal agents.

Adult↗

In vitro studies with cefotaxime: disk diffusion susceptibility tests.

Until recently two sets of conflicting interpretive criteria existed for use with the standardized 30-mug cefotaxime diffusion disk [National Committee for Clinical Laboratory Standards (NCCLS) M2-A2S, supplement 1; product information package insert for Claforan (cefotaxime sodium), edition 10/81.] The latter criteria recently were superseded by a third set which differs radically from the first two in both minimal inhibitory concentration (MIC) and zone size breakpoints. The first two sets of criteria differed mainly in the zone of inhibition diameters used to predict resistant and intermediate organisms. The accuracies of these two sets of criteria were evaluated by paired agar dilution (World Health Organization-International Collaborative Study) and disk diffusion tests (Food and Drug Administration) with 347 clinical isolates of aerobic bacteria. A total of 274 isolates (79%) were clinically susceptible by agar dilution as defined by NCCLS (MIC </=8 mug/ml) and 61, including 48 Pseudomonas spp., were of intermediate susceptibility (MIC of 16 or 32 mug/ml). Twelve were resistant (MIC >/=64 mug/ml). The original product information package insert criteria proved to be most unreliable in identification of the intermediate organisms (zone of inhibition diameters of 18 to 22 mm); only 5 were correctly predicted as being intermediate, whereas 54 were predicted as being resistant, and 2 were predicted as being susceptible. In contrast, the NCCLS criteria (zone of inhibition diameter of 15 to 22 mm) predicted 41 as being intermediate and 18 as being resistant; again, 2 were susceptible. The 12 isolates resistant to cefotaxime by agar dilution were correctly predicted to be resistant by either set of breakpoints (zone of inhibition diameter of </=14 or </=17 mm). These results suggest that the package insert criteria previously recommended for use with the 30-mug cefotaxime disk were overly conservative and required revision to bring them into agreement with NCCLS performance standards. Unfortunately however, the recent revision of the package insert criteria has further confused this issue [product information package insert for Claforan (cefotaxime sodium), edition 2/82].

Bacteria↗

Serotype B/C Cryptococcus neoformans isolated from patients in nonendemic areas.

Of 90 clinical isolates of Cryptococcus neoformans studied, 3 were determined to be serotype B/C. The patients from whom these B/C isolates were obtained were identified as never having lived in or visited the areas associated with B/C serotypes. This finding suggests a broader geographic distribution of this serotype group than previously believed. The glycine-cycloheximide-phenol red medium described by Salkin and Hurd (J. Clin. Microbiol. 15:169-171, 1982) was shown to be more accurate in differentiating A/D and B/D serotype pairs of C. neoformans than the creatinine-dextrose-bromthymol blue medium described by Kwon-Chung et al. (Int. J. Syst. Bacteriol. 28:616-620, 1978).

Cryptococcosis↗

A comparison of bifonazole (BAY H 4502) with clotrimazole in vitro.

The antifungal activity of a new topical imidazole, bifonazole (BAY h 4502, Bayer AG Institute for Chemotherapy), was compared in vitro with that of clotrimazole (BAY b 5097, Schering Corporation) in tests with 67 pathogenic and commensal yeasts, 45 dermatophytes and 14 miscellaneous pathogenic fungi by an agar dilution method. Three media, Kimmig's agar, Sabouraud's agar, and casein-yeast extract-glucose agar were used. Bifonazole was inhibitory for nearly all the yeasts tested including Candida albicans, C. parapsilosis, and Torulopsis glabrata with geometric mean minimal inhibitory concentrations (G-MIC) averaging 5 micrograms ml-1 on all three media. Clotrimazole was the more active drug against these same species with G-MIC's ranging from 0 . 25 to 2 . 10 micrograms ml-1. Results with bifonazole were affected by choice of medium with Kimmig's agar generally giving the lowest MIC's; results with clotrimazole were also affected by choice of medium but to a lesser degree. In nearly all instances, both bifonazole and clotrimazole were inhibitory for the dermatophytic fungi at concentrations of 0 . 50 micrograms ml-1 or less and clotrimazole was the more active drug. Choice of medium was, in general, not a factor with these latter fungi which included Epidermophyton, Trichophyton, and Microsporum species. Both drugs were active against species of Aspergillus (G-MIC's of 3 . 18 micrograms ml-1), Fusarium (G-MIC's ranging from 1 . 59 to 12 . 70 micrograms ml-1) and Scopulariopsis (G-MIC's of 1 . 78 micrograms ml-1); clotrimazole was the more active drug by factors of 2- to 4-fold on all three media. Bifonazole MICs were shown to vary with pH (maximal activity at pH 6 . 5) with selected yeasts when tested on Kimmig's agar. Differences in results obtained with varying inoculum sizes for these same yeasts generally were unremarkable. With selected species of yeasts and dermatophytes, it was determined that the ratio of minimal fungicidal to inhibitory concentrations (MFC/MIC) was much lower for bifonazole than for clotrimazole.

Antifungal Agents↗

N-formimidoyl thienamycin (MK0787): in vitro study.

N-Formimidoyl thienamycin (MK0787) was compared in vitro with three other beta-lactam and two aminoglycoside antibiotics. It was second in activity only to cefotaxime against members of the Enterobacteriaceae and to amikacin against Pseudomonas species. It was the most active antibiotic against Staphylococcus aureus. Resistance (minimal inhibitory concentration, greater than 128 microgram/ml) to N-formimidoyl thienamycin was not observed.

Anti-Bacterial Agents↗

The evolution of pulmonary cryptococcosis: clinical implications from a study of 41 patients with and without compromising host factors.

Over 14 years 41 patients were diagnosed as having pulmonary cryptococcosis. Cryptococcus neoformans remained localized to the lung in 12 cases and disseminated in the remaining 29. Thirty-four patients were compromised hosts. Disseminated disease developed in 28 of these 34, and four of these 28 patients with disseminated disease presented with concomitant pulmonary and meningeal infections. In all the remaining 24 central nervous system involvement developed 2 to 20 weeks after the finding of an abnormal chest roentgenogram. Seven patients were normal hosts, and in six of these cases disease remained localized to the lung. Four important conclusions were drawn from this study: pulmonary cryptococcosis is rarely considered in the differential diagnosis of an abnormal chest roentgenogram, thereby leading to missed diagnoses and therapeutic errors; the natural history of untreated pulmonary cryptococcosis in compromised hosts is extrapulmonic dissemination; compromised hosts with pulmonary cryptococcosis should receive antifungal therapy because of a high propensity for dissemination; and normal hosts in whom dissemination has been excluded generally do not need antifungal therapy.

Adolescent↗

Dematiaceous fungal pathogens isolated from nature.

This study was conducted to demonstrate the presence of pathogenic dematiaceous fungi in nature. Using hamster and mouse inoculation techniques, 43 isolates of dematiaceous fungi were recovered from 39 samples of woody plant material and soil from the Virginia environment. Thirteen species were identified and included 4 Phialophora spp., 3 Cladosporium spp., 2 Exophiala spp., Sporothrix sp., Wangiella dermatitidis, Bispora betulina, and Scytalidium lignicola. Evidence is presented for the first isolations of C. trichoides from nature in the United States; these isolates proved to be pathogenic for mice in which they produced disease and death in a course similar to that seen in man. Natural isolates of Phialophora verrucosa, Phialophora repens, Exophiala jeanselmei, and Wangiella dermatitidis were identical to those species isolated from man using the following criteria: morphology, 12% gelatin reaction, and survival in laboratory animals.

Animals↗

In-vitro activities of cefamandole and cephalothin against 1,881 clinical isolates. A multi-center study.

By use of an agardilution technic, 1,881 clinical isolates were tested against cefamandole and cephalothin. The isolates represented 18 genera, recovered in five geographically separate centers within the United States. The majority of strains were susceptible (MICs less than or equal to 8 micrograms/ml) to both drugs. Cefamandole showed greater activity against most of the bacterial pathogens. Enterococci, Serratia spp., and Acinetobacter spp. were resistant to both drugs. Cephalothin was more active against Staphylococcus aureus, and both cephalosporins were relatively inactive against methicillin-resistant strains of S. aureus. Enterobacter spp. and indole-positive Proteus spp. were susceptible to cefamandole but resistant to cephalothin.

Bacteria↗

Detection of candida antigenemia by counterimmunoelectrophoresis in patients with invasive candidiasis.

Because of the difficulty in diagnosis of invasive candidiasis, an assay that makes use of counterimmunoelectrophoresis (CIE) was developed to detect candida antigen. A cell-wall polysaccharide of Candida was extracted with hot formamide, ethanol precipitation, and gel filtration. Rabbit antiserum was tested by CIE against sera from 20 healthy individuals, 15 patients with mucosal candidiasis, and 48 compromised patients with cultures positive for Candida. Antigen was detected in sera from 13 patients by CIE; eight of these patients were eventually proven to have invasive disease. None of the antigen-negative patients for whom autopsy was performed had evidence of invasive candidiasis. Healthy individuals and patients with superficial mucosal candidiasis were also antigen-negative. The detection of candida antigenemia by CIE is specific for invasive disease and serves as a guide in initiation and follow through of antifungal therapy.

Animals↗

Fungus balls of the urinary tract.

Fungus balls of the urinary tract are rare and usually associated with infection by Candid albicans. Since 1968 five patients seen at the Medical College of Virginia Hospitals presented with this peculiar manifestation of candidiasis. Summaries of their epidemiologic clinical, pathologic, and mycologic data are presented. All Candida fungus balls involved the upper collecting system and were detected by radiography and confirmed by culture and/or pathologic section. Two of the five patients completely recovered. Three patients were treated with flucytosine and/or local irrigation with a polyene antifungal agent. Two recovered and the third died of probable bacterial sepsis. One patient was treated successfully with surgical removal of the fungus ball and a brief period of local irrigation with amphotericin B (AMB). The fifth patient recovered after 28 days of parenteral AMB. Predisposing factors and pathogenetic mechanisms are discussed, and a rational approach to therapy is outlined.

Adult↗