Sertaconazole antifungal profile determined by a microdilution method versus nine topical substances against dermatophyte fungi.

Antifungal activity and in vitro inhibition time for sertaconazole (STZ) and 9 other topical drugs, namely amorolfine, bifonazole, clotrimazole, econazole, ketoconazole, miconazole, oxiconazole, terbinafine, and tioconazole were determined against 124 clinical isolates of dermatophyte (12 species) fungi by the microdilution method in a liquid medium and the measurement of optical density. STZ's antifungal activity was not always affected by the tested dermatophyte genus, as was the case with the remaining antifungals. In vitro antifungal activity was at the same level for all the studied azole derivatives, but, in terms of partial inhibitory concentrations, STZ starts its in vitro inhibitory activity in a shorter time than the other tested substances, particularly in those incubation periods when the growth of the dermatophyte fungi was more developed.

Antifungal activity of posaconazole against Candida spp. and non-Candida clinical yeasts isolates.

The in vitro antifungal activity of posaconazole was tested against 315 yeast clinical isolates and 11 ATCC reference strains by means an agar diffusion method (Neosensitabs, Rosco,Denmark) based in CLSI M44-A2 document. Posaconazole activity was excellent against Cryptococcus and Rhodotorula species studied and showed very good activity against most species of Candida tested. A total of 13 clinical isolates (4.1%) were resistant: Candida albicans (n=5), Candida glabrata (n=5), Candida tropicalis (n=1), Geotrichum australiensis (n=1) and Geotrichum capitatum (n=1). Our results suggest posaconazole is an effective antifungal agent against the most clinically important yeasts species (92.7% of susceptibility). Agar diffusion method provides good conditions for the posaconazole susceptibility study in the routine laboratory.

[Determination of the in vitro antifungal susceptibility of clinically important yeasts using the Sensititre system]. / Determinación mediante el sistema Sensititre de la sensibilidad in vitro a los antifúngicos de levaduras de interés médico.

Using Sensititre (AccuMed, USA) we studied the in vitro antifungal activity of amphotericin B, fluconazole, itraconazole, ketoconazole and 5-fluorocytosine against 250 clinical yeast isolates taken from different hospitals, including Candida (151 C. albicans, 15 C. krusei, 14 C. parapsilosis, 11 C. tropicalis, 10 C. glabrata, 4 C. guilliermondii, 3 C. rugosa, 2 C. viswanathii, 2 C. famata and 2 C. kefyr), Cryptococcus (32 C. neoformans and 1 C. laurentii), Trichosporon (2 isolates) and Rhodotorula rubra (1 isolate). All the strains were susceptible to amphotericin B and showed an MIC <1 mg/l. The susceptibility of C. albicans (MIC(90) <256 mg/l), C. krusei (MIC(90) <64 mg/l), C. glabrata (MIC(90) <64 mg/l) and C. neoformans (MIC(90) 32 mg/l) to fluconazole was lower (14% isolates being resistant and 16.8% susceptible depending on the dose). The largest number of strains resistant to itraconazole was observed in C. albicans and C. glabrata (17.2% resistant and 24% susceptible and susceptible depending on the dose, respectively). Ketoconazole and 5-fluorocytosine were not effective in vitro against 12.8% and 2%, respectively, of all the isolates studied. Nine C. krusei and seven C. neoformans (12.9%) showed dose-dependent susceptibility to 5-fluorocytosine.

Comparative study of the in vitro antifungal activity of bifonazole, naftifine and sertaconazole against yeasts.

The in vitro activity of three antifungal agents was tested and compared against 151 yeast strains, including ten Candida species, Cryptococcus neoformans, Rhodotorula rubra, and Trichosporon cutaneum. Minimum inhibitory concentrations (MICs) were determined by a microdilution technique in Shadomy modified liquid medium. The mean MICs of sertaconazole (0.34 mg/L) were lower than those of naftifine (16.3 mg/L) and bifonazole (13.2 mg/L). These results suggest that sertaconazole is more active against Candida spp than other topical agents such as bifonazole and naftifine.

[Comparison of two methods for the study of the in vitro susceptibility to sertaconazole of yeast clinical isolates]. / Comparación de dos métodos para el estudio de la sensibilidad in vitro al sertaconazol en aislamientos clínicos de levaduras.

We evaluated a commercial method for studying the in vitro susceptibility to sertaconazole based on its diffusion in agar with standardized tablets, with the aim of determining its correlation with the method of microdilution in Shadomy modified liquid medium (YNBg). A total of 110 Candida genus strains (50 C. albicans, 26 C. tropicalis, 15 C. glabrata, 8 C. parapsilosis, 8 C. krusei, 2 C. guilliermondii and 1 C. kefyr) from pathological clinical processes were used. The results of both techniques showed a statistically significant correlation that depended on the type of reading used in the liquid medium microdilution technique, with results being -0. 4199 with IC50; -5135 with IC90: -0.6634 with MIC24 h; and -0.4945 with MIC48 h. These values demonstrate the existence of a correlation for sertaconazole, and that it is bigger when it is compared with the logarithm of the MIC obtained after 24 hours of incubation.

Comparative study of antifungal activity of sertaconazole, terbinafine, and bifonazole against clinical isolates of Candida spp., Cryptococcus neoformans and dermatophytes.

The in vitro activity of sertaconazole was compared with that of terbinafine and bifonazole against 180 Candida spp., Cryptococcus neoformans yeasts and 53 dermatophytes. Minimum inhibitory concentrations (MICs) were determined by a microdilution method in Sabouraud's buffered liquid medium (pH 5.6). Sertaconazole (arithmetic mean MIC 1.24 mg/l) was statistically more active than bifonazole (MIC 6.54 mg/l) and terbinafine (MIC 12.61 mg/l) against yeasts strains, MIC values for sertaconazole being generally and specifically lower for each tested yeast species. MIC for C. parapsilosis (0.26 mg/l) demonstrated a higher activity of sertaconazole against this species, in contrast to C. tropicalis (MIC 1.49 mg/l). Against dermatophytes, MIC for terbinafine (0.05 mg/l) was lower than sertaconazole (MIC 0.41 mg/l) and bifonazole (MIC 1.04 mg/l). These results, obtained under the same experimental conditions, confirm the good antifungal activity of sertaconazole against both yeasts and dermatophytes with lower MICs obtained in the topical application. This in vitro activity correlates with the clinical efficacy of sertaconazole compared with other antifungal agents.