scholarly journals Metarrhizium anisopliae as a Cause of Sinusitis in Immunocompetent Hosts

1999 ◽  
Vol 37 (1) ◽  
pp. 195-198 ◽  
Author(s):  
Sanjay G. Revankar ◽  
Deanna A. Sutton ◽  
Stephen E. Sanche ◽  
Jyothi Rao ◽  
Marcus Zervos ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Susceptibility Testing ◽  
Chronic Sinusitis ◽  
Clinical Laboratory ◽  
Antifungal Susceptibility ◽  
National Committee ◽  
Insect Populations ◽  
Clinically Significant ◽  
Control Insect

Metarrhizium anisopliae is a common pathogen of insects and has even been used to control insect populations. It is rarely isolated from human or animal sources, but recently, there have been three reported cases of disease, two in humans and one in a cat. We present our experience with five isolates from human sources, including two that were the apparent causes of two cases of sinusitis in immunocompetent hosts. The first patient was a 36-year-old male with frontal and ethmoid sinusitis, and the second was a 79-year-old female with chronic sinusitis. Both patients underwent surgery, and pathology of the surgical specimens revealed branching hyphae. Cultures grew onlyMetarrhizium species. Neither patient received antifungal therapy, and both did well postoperatively. The other three isolates were cultured from bronchoalveolar lavage specimens but were not felt to be clinically significant. Antifungal susceptibility testing using the National Committee for Clinical Laboratory Standards macrobroth method revealed that all isolates were resistant to amphotericin B, 5-flucytosine, and fluconazole. Itraconazole and newer azole compounds were more active. Metarrhizium species may cause disease in humans, even those without evidence of immunosuppression, and are apparently highly resistant to amphotericin B in vitro.

Use of spectrophotometric reading for in vitro antifungal susceptibility testing ofAspergillusspp.

1999 ◽  
Vol 45 (10) ◽  
pp. 871-874 ◽  
Author(s):  
Eric Dannaoui ◽  
Florence Persat ◽  
Marie-France Monier ◽  
Elisabeth Borel ◽  
Marie-Antoinette Piens ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Antifungal Susceptibility ◽  
Reference Method ◽  
Antifungal Susceptibility Testing ◽  
Aspergillus Species ◽  
National Committee ◽  
Broth Microdilution Method

A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.Key words: antifungal, susceptibility testing, Aspergillus, spectrophotometric reading.

scholarly journals Comparison of a spectrophotometric microdilution method with RPMI-2% glucose with the National Committee for Clinical Laboratory Standards reference macrodilution method M27-P for in vitro susceptibility testing of amphotericin B, flucytosine, and fluconazole against Candida albicans.

1996 ◽  
Vol 40 (9) ◽  
pp. 1998-2003 ◽  
Author(s):  
J L Rodríguez-Tudela ◽  
J Berenguer ◽  
J V Martínez-Suárez ◽  
R Sanchez
Keyword(s):  
Quality Control ◽  
Candida Albicans ◽  
Amphotericin B ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Antifungal Susceptibility ◽  
National Committee ◽  
Microdilution Method ◽  
Reference Strains

The National Committee for Clinical Laboratory Standards has proposed a reference broth macrodilution method for in vitro antifungal susceptibility testing of yeasts (the M27-P method). This method is cumbersome and time-consuming and includes MIC endpoint determination by visual and subjective inspection of growth inhibition after 48 h of incubation. An alternative microdilution procedure was compared with the M27-P method for determination of the amphotericin B, flucytosine, and fluconazole susceptibilities of 8 American Type Culture Collection strains (6 of them were quality control or reference strains) and 50 clinical isolates of candida albicans. This microdilution method uses as culture medium RPMI 1640 supplemented with 18 g of glucose per liter (RPMI-2% glucose). Preparation of drugs, basal medium, and inocula was done by following the recommendations of the National Committee for Clinical Laboratory Standards. The MIC endpoint was calculated objectively from the turbidimetric data read at 24 h. Increased growth of C. albicans in RPMI-2% glucose and its spectrophotometric reading allowed for the rapid (24 h) and objective calculation of MIC endpoints compared with previous microdilution methods with standard RPMI 1640. Nevertheless, good agreement was shown between the M27-P method and this microdilution test. The MICs obtained for the quality control or reference strains by the microdilution method were in the ranges published for those strains. For clinical isolates, the percentages of agreement were 100% for amphotericin B and fluconazole and 98.1% for flucytosine. These data suggest that this microdilution method may serve as a less subjective and more rapid alternative to the M27-P method for antifungal susceptibility testing of yeasts.

scholarly journals Evaluation of Amphotericin B Interpretive Breakpoints for Candida Bloodstream Isolates by Correlation with Therapeutic Outcome

2006 ◽  
Vol 50 (4) ◽  
pp. 1287-1292 ◽  
Author(s):  
Benjamin J. Park ◽  
Beth A. Arthington-Skaggs ◽  
Rana A. Hajjeh ◽  
Naureen Iqbal ◽  
Meral A. Ciblak ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
National Committee ◽  
Restricted Range ◽  
Broth Microdilution ◽  
Therapeutic Success ◽  
In Vitro Susceptibility ◽  
In Vitro Susceptibility Testing

ABSTRACT One hundred seven Candida bloodstream isolates (51 C. albicans, 24 C. glabrata, 13 C. parapsilosis, 13 C. tropicalis, 2 C. dubliniensis, 2 C. krusei, and 2 C. lusitaniae strains) from patients treated with amphotericin B alone underwent in vitro susceptibility testing against amphotericin B using five different methods. Fifty-four isolates were from patients who failed treatment, defined as death 7 to 14 days after the incident candidemia episode, having persistent fever of ≥5 days' duration after the date of the incident candidemia, or the recurrence of fever after two consecutive afebrile days while on antifungal treatment. MICs were determined by using the Clinical Laboratory Standards Institute (formally National Committee for Clinical Laboratory Standards) broth microdilution procedure with two media and by using Etest. Minimum fungicidal concentrations (MFCs) were also measured in two media. Broth microdilution tests with RPMI 1640 medium generated a restricted range of MICs (0.125 to 1 μg/ml); the corresponding MFC values ranged from 0.5 to 4 μg/ml. Broth microdilution tests with antibiotic medium 3 produced a broader distribution of MIC and MFC results (0.015 to 0.25 μg/ml and 0.06 to 2 μg/ml, respectively). Etest produced the widest distribution of MICs (0.094 to 2 μg/ml). However, none of the test formats studied generated results that significantly correlated with therapeutic success or failure.

scholarly journals Correlation between Antifungal Susceptibilities ofCoccidioides immitis In Vitro and Antifungal Treatment with Caspofungin in a Mouse Model

2001 ◽  
Vol 45 (6) ◽  
pp. 1854-1859 ◽  
Author(s):  
Gloria M. González ◽  
Rolando Tijerina ◽  
Laura K. Najvar ◽  
Rosie Bocanegra ◽  
Michael Luther ◽  
...  
Keyword(s):  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Antifungal Susceptibility ◽  
National Committee ◽  
In Vitro Susceptibility ◽  
Minimum Effective Concentration ◽  
Study Results ◽  
Significant Difference

ABSTRACT Caspofungin (Merck Pharmaceuticals) was tested in vitro against 25 clinical isolates of Coccidoides immitis. In vitro susceptibility testing was performed in accordance with the National Committee for Clinical Laboratory Standards document M38-P guidelines. Two C. immitis isolates for which the caspofungin MICs were different were selected for determination of the minimum effective concentration (MEC), and these same strains were used for animal studies. Survival and tissue burdens of the spleens, livers, and lungs were used as antifungal response markers. Mice infected with strain 98-449 (48-h MIC, 8 μg/ml; 48-h MEC, 0.125 μg/ml) showed 100% survival to day 50 when treated with caspofungin at ≥1 mg/kg. Mice infected with strain 98-571 (48-h MIC, 64 μg/ml; 48-h MEC, 0.125 μg/ml) displayed ≥80% survival when the treatment was caspofungin at ≥5 mg/kg. Treatment with caspofungin at 0.5, 1, 5, or 10 mg/kg was effective in reducing the tissue fungal burdens of mice infected with either isolate. When tissue fungal burden study results were compared between strains, caspofungin showed no statistically significant difference in efficacy in the organs of the mice treated with both strains. A better in vitro-in vivo correlation was noted when we used the MEC instead of the MIC as the endpoint for antifungal susceptibility testing. Caspofungin may have a role in the treatment of coccidioidomycosis.

scholarly journals Microdilution Susceptibility Testing of Amphotericin B, Itraconazole, and Voriconazole against Clinical Isolates of Aspergillus and FusariumSpecies

1999 ◽  
Vol 37 (12) ◽  
pp. 3946-3951 ◽  
Author(s):  
Sevtap Arikan ◽  
Mario Lozano-Chiu ◽  
Victor Paetznick ◽  
Sunaina Nangia ◽  
John H. Rex
Keyword(s):  
Aspergillus Fumigatus ◽  
Amphotericin B ◽  
Fusarium Solani ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Narrow Range ◽  
National Committee ◽  
In Vitro Activity ◽  
Microdilution Method

We compared the activities of amphotericin B, itraconazole, and voriconazole against clinical Aspergillus(n = 82) and Fusarium (n= 22) isolates by a microdilution method adopted from the National Committee for Clinical Laboratory Standards (NCCLS-M27A). RPMI 1640 (RPMI), RPMI 1640 supplemented to 2% glucose (RPMI-2), and antibiotic medium 3 supplemented to 2% glucose (AM3) were used as test media. MICs were determined after 24, 48, and 72 h. A narrow range of amphotericin B MICs was observed for Aspergillus isolates, with minor variations among species. MICs for Fusariumisolates were higher than those for Aspergillus isolates. MICs of itraconazole were prominently high for two previously defined itraconazole-resistant Aspergillus fumigatus isolates andFusarium solani. Voriconazole showed good in vitro activity against itraconazole-resistant isolates, but the MICs of voriconazole for F. solani were high. RPMI was the most efficient medium for detection of itraconazole-resistant isolates, followed by RPMI-2. While the significance remains unclear, AM3 lowered the MICs, particularly those of amphotericin B.

scholarly journals Clinical Evaluation of the ASTY Colorimetric Microdilution Panel for Antifungal Susceptibility Testing

1998 ◽  
Vol 36 (9) ◽  
pp. 2609-2612 ◽  
Author(s):  
M. A. Pfaller ◽  
S. Arikan ◽  
M. Lozano-Chiu ◽  
Y.-S. Chen ◽  
S. Coffman ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Amphotericin B ◽  
Excellent Agreement ◽  
Antifungal Agents ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Antifungal Susceptibility ◽  
Reference Method ◽  
National Committee ◽  
Microdilution Method

A method using a commercially prepared colorimetric microdilution panel (ASTY; Kyokuto Pharmaceutical Industrial Co., Ltd.) was compared in four different laboratories with the National Committee for Clinical Laboratory Standards (NCCLS) reference microdilution method by testing 802 clinical isolates of Candida spp. (C. albicans, C. glabrata, C. tropicalis,C. parapsilosis, C. krusei, C. lusitaniae, C. guilliermondii, C. lipolytica, C. rugosa, and C. zeylanoides) against amphotericin B, 5-fluorocytosine (5FC), fluconazole, and itraconazole. Reference MIC endpoints were established after 48 h of incubation, and ASTY endpoints were established after 24 and 48 h of incubation. ASTY endpoints were determined to be the time at which the color of the first well changed from red (indicating growth) to purple (indicating growth inhibition) or blue (indicating no growth). Excellent agreement (within 2 dilutions) between the reference and colorimetric MICs was observed. Overall agreement was 93% at 24 h and 96% at 48 h. Agreement ranged from 90% with itraconazole and 5FC to 96% with amphotericin B at 24 h and from 92% with itraconazole to 99% with amphotericin B and 5FC at 48 h. The ASTY colorimetric microdilution panel method appears to be comparable to the NCCLS reference method for testing the susceptibilities of Candida spp. to a variety of antifungal agents.

scholarly journals The Trailing End Point Phenotype in Antifungal Susceptibility Testing Is pH Dependent

1999 ◽  
Vol 43 (6) ◽  
pp. 1383-1386 ◽  
Author(s):  
Kieren A. Marr ◽  
Tige R. Rustad ◽  
John H. Rex ◽  
Theodore C. White
Keyword(s):  
Minimal Medium ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Ph Effect ◽  
Antifungal Susceptibility ◽  
Drug Susceptibility ◽  
Drug Susceptibility Testing ◽  
National Committee ◽  
End Points

ABSTRACT The interpretation of end points in azole antifungal drug susceptibility testing is problematic, in part due to incomplete growth inhibition of Candida species. Such trailing growth can cause the MICs of fluconazole for some isolates to be low (<1 μg/ml) after 24 h of growth but much higher (>64 μg/ml) after 48 h. Isolates having this type of growth have been described as having a low-high phenotype. Although these isolates would be considered resistant by current National Committee of Clinical Laboratory Standards definitions, growing evidence suggests that they are susceptible in vivo. To further characterize these isolates in vitro, microdilution susceptibility testing comparing the complex defined medium RPMI 1640 to a defined minimal medium (yeast nitrogen broth) was performed. Isolates having trailing growth in MOPS (morpholinepropanesulfonic acid)-buffered RPMI 1640 (pH 7.0) were found to have clear end points in the minimal medium at its native pH of 4.5. The pH of the medium influenced the low-high phenotype, as these same isolates trailed in minimal medium adjusted to a pH of ≥6.0 but did not trail in RPMI 1640 adjusted to a pH of ≤5.0. This pH effect was independent of the medium buffering capacity, as trailing was decreased in both minimal medium and RPMI 1640 (pH 4.5) buffered in citrate. Adjustment in the pH of MOPS-buffered RPMI 1640 reduced trailing in multiple strains of Candida albicans without affecting the MICs for isolates having known susceptible (low-low) and resistant (high-high) phenotypes. Adjustment of the medium pH could be considered to eliminate trailing in azole drug susceptibility testing.

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