Evaluación de la actividad antimicótica de ketoconazol en cepas de Microsporum sp y preparación de una forma farmacéutica en crema

Abstract

The main objective of this research study was to focus on fungal infections, such as those caused by dermatophytes, which are showing resistance or even multiple resistance to antifungal treatments, which has become a significant public health challenge. Recent data on the sensitivity of these microorganisms to antifungal agents is essential to ensure the timely delivery of effective treatment. This research aimed to evaluate the Minimum Inhibitory Concentration (MIC) in strains of Microsporum canis and to formulate a pharmaceutical cream. The microorganism was isolated from infected domestic animals using Mycosel agar as a culture medium for three months, but the results were unsuccessful. Following Dr Giovanna Albán's suggestion, the keratin hook technique was used, using horsehair as an attractant and collecting soil samples in areas with a high concentration of animals, which finally allowed the isolation of the desired strain. Then, an adapted version of the microtiter technique from the CLSI M38-A manual was applied to determine the minimum inhibitory concentration in filamentous fungi, obtaining a MIC value of 4 µg/mL. Since this manual lacks cut-off points for ketoconazole (KTZ), those established in Fungitest were used, classifying the MIC obtained as intermediate sensitivity. Upon confirmation of the sensitivity of the micro-organism to the drug, as a final step, two formulations of KTZ cream were developed. The formulation including EDTA showed a prolonged shelf life compared to the other variant, standing out as a more effective option in terms of drug preservation.