Dermatophytic Biofilms: Characteristics, Significance and Treatment Approaches.

Microbes are found in the environment, possibly more often as biofilms than in planktonic forms. Biofilm formation has been described for several important fungal species. The presence of a dermatophytoma in a dermatophytic nail infection was the basis for the proposal that dermatophytes form biofilms as well. This could explain treatment failure and recurrent dermatophytic infections. Several investigators have performed in vitro and ex vivo experiments to study the formation of biofilms by dermatophytes and their properties. The nature of the biofilm structure itself contributes to fungal protection mechanisms against many harmful external agents, including antifungals. Thus, a different approach should be carried out regarding susceptibility testing and treatment. Concerning susceptibility testing, methods to evaluate either the inhibition of biofilm formation, or the ability to eradicate it, have been introduced. As for treatment, in addition to classical antifungal agents, some natural formulations, such as plant extracts or biosurfactants, and alternative approaches, such as photodynamic therapy, have been proposed. Studies that connect the results of the in vitro and ex vivo experimentation with clinical outcomes are required in order to verify the efficacy of these approaches in clinical practice.

Paving the Way to Overcome Antifungal Drug Resistance: Current Practices and Novel Developments for Rapid and Reliable Antifungal Susceptibility Testing.

The past year has established the link between the COVID-19 pandemic and the global spread of severe fungal infections; thus, underscoring the critical need for rapid and realizable fungal disease diagnostics. While in recent years, health authorities, such as the Centers for Disease Control and Prevention, have reported the alarming emergence and spread of drug-resistant pathogenic fungi and warned against the devastating consequences, progress in the diagnosis and treatment of fungal infections is limited. Early diagnosis and patient-tailored therapy are established to be key in reducing morbidity and mortality associated with fungal (and cofungal) infections. As such, antifungal susceptibility testing (AFST) is crucial in revealing susceptibility or resistance of these pathogens and initiating correct antifungal therapy. Today, gold standard AFST methods require several days for completion, and thus this much delayed time for answer limits their clinical application. This review focuses on the advancements made in developing novel AFST techniques and discusses their implications in the context of the practiced clinical workflow. The aim of this work is to highlight the advantages and drawbacks of currently available methods and identify the main gaps hindering their progress toward clinical application.

Antifungal Combinations in Dermatophytes.

Dermatophytes are the most common cause of fungal infections worldwide, affecting millions of people annually. The emergence of resistance among dermatophytes along with the availability of antifungal susceptibility procedures suitable for testing antifungal agents against this group of fungi make the combinatorial approach particularly interesting to be investigated. Therefore, we reviewed the scientific literature concerning the antifungal combinations against dermatophytes. A literature search on the subject performed in PubMed yielded 68 publications: 37 articles referring to in vitro studies and 31 articles referring to case reports or clinical studies. In vitro studies involved over 400 clinical isolates of dermatophytes (69% Trichophyton spp., 29% Microsporum spp., and 2% Epidermophyton floccosum). Combinations included two antifungal agents or an antifungal agent plus another chemical compound including plant extracts or essential oils, calcineurin inhibitors, peptides, disinfectant agents, and others. In general, drug combinations yielded variable results spanning from synergism to indifference. Antagonism was rarely seen. In over 700 patients with documented dermatophyte infections, an antifungal combination approach could be evaluated. The most frequent combination included a systemic antifungal agent administered orally (i.e., terbinafine, griseofulvin, or azole-mainly itraconazole) plus a topical medication (i.e., azole, terbinafine, ciclopirox, amorolfine) for several weeks. Clinical results indicate that association of antifungal agents is effective, and it might be useful to accelerate the clinical and microbiological healing of a superficial infection. Antifungal combinations in dermatophytes have gained considerable scientific interest over the years and, in consideration of the interesting results available so far, it is desirable to continue the research in this field.

The unprecedented epidemic-like scenario of dermatophytosis in India: III. Antifungal resistance and treatment options.

One of the canonical features of the current outbreak of dermatophytosis in India is its unresponsiveness to treatment in majority of cases. Though there appears to be discordance between in vivo and in vitro resistance, demonstration of in vitro resistance of dermatophytes to antifungals by antifungal susceptibility testing is essential as it may help in appropriate management. The practical problem in the interpretation of antifungal susceptibility testing is the absence of clinical breakpoints and epidemiologic cutoff values. In their absence, evaluation of the upper limit of a minimal inhibitory concentration of wild type isolates may be beneficial for managing dermatophytosis and monitoring the emergence of isolates with reduced susceptibility. In the current scenario, most of the cases are unresponsive to standard dosages and duration of treatment recommended until now. This has resulted in many ex-cathedra modalities of treatment that are being pursued without any evidence. There is an urgent need to carry out methodical research to develop an evidence base to formulate a rational management approach in the current scenario.

Antifungal Susceptibility Testing and Identification.

The requirement for antifungal susceptibility testing is increasing given the availability of new drugs, increasing populations of individuals at risk for fungal infection, and emerging multiresistant fungi. Rapid and accurate fungal identification remains at the forefront of laboratory efforts to guide empiric therapy. Antifungal susceptibility testing methods have greatly improved, but are subject to variation in results between methods. Careful standardization, validation, and extensive training of users is essential to ensure susceptibility results are clinically useful and interpreted appropriately. Interpretive criteria for many drugs and species are still lacking, but this will continue to evolve.

The Neosartorya fischeri Antifungal Protein 2 (NFAP2): A New Potential Weapon against Multidrug-Resistant Candida auris Biofilms.

Candida auris is a potential multidrug-resistant pathogen able to persist on indwelling devices as a biofilm, which serve as a source of catheter-associated infections. Neosartorya fischeri antifungal protein 2 (NFAP2) is a cysteine-rich, cationic protein with potent anti-Candida activity. We studied the in vitro activity of NFAP2 alone and in combination with fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin against C. auris biofilms. The nature of interactions was assessed utilizing the fractional inhibitory concentration index (FICI), a Bliss independence model, and LIVE/DEAD viability assay. NFAP2 exerted synergy with all tested antifungals with FICIs ranging between 0.312-0.5, 0.155-0.5, 0.037-0.375, 0.064-0.375, and 0.064-0.375 for fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin, respectively. These results were confirmed using a Bliss model, where NFAP2 produced 17.54 µM2%, 2.16 µM2%, 33.31 µM2%, 10.72 µM2%, and 111.19 µM2% cumulative synergy log volume in combination with fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin, respectively. In addition, biofilms exposed to echinocandins (32 mg/L) showed significant cell death in the presence of NFAP2 (128 mg/L). Our study shows that NFAP2 displays strong potential as a novel antifungal compound in alternative therapies to combat C. auris biofilms.

Antifungal susceptibility testing practices in mycology laboratories in France, 2018.

A survey of mycology laboratories for antifungal susceptibility testing (AFST) was undertaken in France in 2018, to better understand the difference in practices between the participating centers and to identify the difficulties they may encounter as well as eventual gaps with published standards and guidelines. The survey captured information from 45 mycology laboratories in France on how they perform AFST (number of strains tested, preferred method, technical and quality aspects, interpretation of the MIC values, reading and interpretation difficulties). Results indicated that 86% of respondents used Etest as AFST method, with a combination of one to seven antifungal agents tested. Most of the participating laboratories used similar technical parameters to perform their AFST method and a large majority used, as recommended, internal and external quality assessments. Almost all the participating mycology laboratories (98%) reported difficulties to interpret the MIC values, especially when no clinical breakpoints are available. The survey highlighted that the current AFST practices in France need homogenization, particularly for MIC reading and interpretation.

Successful Treatment of Invasive Fungal Infection Due to Highly Resistant Aspergillus calidoustus in an Allogeneic Hematopoietic Cell Transplant Recipient.

Invasive aspergillosis (IA) is the most common invasive fungal infection following a hematopoietic cell transplant, with emerging cryptic species exhibiting resistance to commonly used antifungals such as azoles. These species have been increasingly found after the introduction of anti-mold prophylaxis. We report a case of a 56-year-old female with primary myelofibrosis whose allogeneic hematopoietic cell transplant was complicated by disseminated fungal infection (skin, lung) due to Aspergillus calidoustus, a cryptic specie. Treatment of Aspergillus species remains challenging as these cryptic species are usually resistant to azoles including voriconazole which is the first line of treatment of IA. Infection was successfully treated with surgical excision and combination antifungal therapy based on in vitro susceptibility and synergy testing. Therapy included isavuconazole, a drug that has been shown to be non-inferior to voriconazole in the treatment of invasive mold infections.

Evaluation of the Gradient Concentration Strip Method for Antifungal Susceptibility Testing of Isavuconazole and Comparators for Mucorales Species.

MIC values for amphotericin B and three azoles determined by the EUCAST reference technique and by gradient concentration strips were compared for 30 Mucorales isolates belonging to clinically important species. Essential agreement (EA) within ±2 dilution steps at 24 hours between the techniques was 83.3% for isavuconazole. EAs for itraconazole, amphotericin B, and posaconazole were 86.7%, 73.3%, and 56.7%, respectively. A good agreement was obtained between visual and spectrophotometric readings for EUCAST.

Improved Methods for Assessing Therapeutic Potential of Antifungal Agents against Dermatophytes and Their Application in the Development of NP213, a Novel Onychomycosis Therapy Candidate.

Onychomycosis is a common, difficult-to-treat nail infection that is mainly caused by dermatophytes. Current therapies are not wholly effective and are associated with manifold side effects. The development of treatments for onychomycosis is challenging because standard in vitro tests are not predictive of antifungal efficacy within the nail. We have developed a new antifungal agent, NP213, for the treatment of onychomycosis. NP213 is based on endogenous host defense peptides produced within the nail. We compared the in vitro activity of NP213 and existing antifungal agents using conventional antimicrobial susceptibility test (AST) systems and more physiologically relevant models based on the human nail. We observed that the standard in vitro AST methodologies failed to predict the efficacy of antifungal agents within the nail. To address that, we present a more physiologically relevant modified AST method. This method, alongside other standard in vitro assessments of activity (including mechanism-of-action and time-of-kill studies), better reflected the activity of NP213 and other antifungal agents within the nail than standard in vitro AST methods. NP213 is a rapidly acting, fungicidal peptide that is superior to existing antifungal agents in vitro It penetrated the nail more effectively than other antifungals, as confirmed by using an optimized in vitro nail infection model. The data presented here support the current clinical development status of NP213 as a novel agent for treating onychomycosis. We propose that the modified tests developed and applied for NP213 characterization are the most relevant to use for screening any potential therapeutic candidates for onychomycosis.

In vitro susceptibilities of Neoscytalidium spp. sequence types to antifungal agents and antimicrobial photodynamic treatment with phenothiazinium photosensitizers.

Neoscytalidium spp. are ascomycetous fungi consisting of pigmented and hyaline varieties both able to cause skin and nail infection. Their color-based identification is inaccurate and may compromise the outcome of the studies with these fungi. The aim of this study was to genotype 32 isolates morphologically identified as Neoscytalidiumdimidiatum or N. dimidiatum var. hyalinum by multilocus sequence typing (MLST), differentiate the two varieties by their sequence types, evaluate their susceptibility to seven commercial antifungal drugs [amphotericin B (AMB), voriconazole (VOR), terbinafine (TER), 5-flucytosine (5FC), ketoconazole (KET), fluconazole (FLU), and caspofungin (CAS)], and also to the antimicrobial photodynamic treatment (APDT) with the phenothiazinium photosensitizers (PS) methylene blue (MB), new methylene blue (NMBN), toluidine blue O (TBO) and the pentacyclic derivative S137. The efficacy of each PS was determined, initially, based on its minimal inhibitory concentration (MIC). Additionally, the APDT effects with each PS on the survival of ungerminated and germinated arthroconidia of both varieties were evaluated. Seven loci of Neoscytalidium spp. were sequenced on MLST revealing eight polymorphic sites and six sequence types (ST). All N. dimidiatum var. hyalinum isolates were clustered in a single ST. AMB, VOR and TER were the most effective antifungal agents against both varieties. The hyaline variety isolates were much less tolerant to the azoles than the isolates of the pigmented variety. APDT with S137 showed the lowest MIC for all the isolates of both varieties. APDT with all the PS killed both ungerminated and germinated arthroconidia of both varieties reducing the survival up to 5 logs. Isolates of the hyaline variety were also less tolerant to APDT. APDT with the four PS also increased the plasma membrane permeability of arthroconidia of both varieties but only NMBN and S137 caused peroxidation of the membrane lipids.

A Novel Polyaminocarboxylate Compound To Treat Murine Pulmonary Aspergillosis by Interfering with Zinc Metabolism.

Aspergillus fumigatus can cause pulmonary aspergillosis in immunocompromised patients and is associated with a high mortality rate due to a lack of reliable treatment options. This opportunistic pathogen requires zinc in order to grow and cause disease. Novel compounds that interfere with fungal zinc metabolism may therefore be of therapeutic interest. We screened chemical libraries containing 59,223 small molecules using a resazurin assay that compared their effects on an A. fumigatus wild-type strain grown under zinc-limiting conditions and on a zinc transporter knockout strain grown under zinc-replete conditions to identify compounds affecting zinc metabolism. After a first screen, 116 molecules were selected whose inhibitory effects on fungal growth were further tested by using luminescence assays and hyphal length measurements to confirm their activity, as well as by toxicity assays on HeLa cells and mice. Six compounds were selected following a rescreening, of which two were pyrazolones, two were porphyrins, and two were polyaminocarboxylates. All three groups showed good in vitro activity, but only one of the polyaminocarboxylates was able to significantly improve the survival of immunosuppressed mice suffering from pulmonary aspergillosis. This two-tier screening approach led us to the identification of a novel small molecule with in vivo fungicidal effects and low murine toxicity that may lead to the development of new treatment options for fungal infections by administration of this compound either as a monotherapy or as part of a combination therapy.

Impact of inappropriate antifungal therapy according to current susceptibility breakpoints on Candida bloodstream infection mortality, a retrospective analysis.

BACKGROUND: The mortality of Candida Bloodstream Infection (CBSI) remains high. Antifungal susceptibility breakpoints were recently updated for Candida species, the impact remains unknown. In this study we evaluated the impact of inappropriate antifungal treatment according to recent breakpoints on 30-day mortality of CBSI. METHODS: From June 2008 to July 2014, data on CBSI episodes from two tertiary-care centers, treated > 72 h were analyzed. Antifungal therapy and 30-day mortality were registered. Inappropriate antifungal treatment according to current Clinical & Laboratory Standards Institute (CLSI) breakpoints was adjusted with 30-day mortality-related co-variates. RESULTS: One hundred forty-nine episodes of CBSI were analyzed. The most frequent species were: C. albicans (40%), C. tropicalis (23%) and C. glabrata complex (20%). According to the 2012 CLSI, 10.7% received inappropriate treatment. The 30-day mortality was 38%; severe sepsis [Odds ratio (OR) 3.4; 95% CI 1.3-8.4], cirrhosis (OR 36; 95% CI 12.2-605), early central venous catheter removal (OR 0.23; 95% CI 0.08-0.66) and previous antifungal therapy (OR 0.15; 95%CI 0.03-0.62), were associated with 30-day mortality by multivariate analysis. Inappropriate antifungal treatment was not (OR 0.19; 95% CI 0.03-1.2). CONCLUSIONS: Appropriate antifungal therapy according to CLSI 2012 did not have an impact on mortality. Mortality of CBSI remains high due to disease severity and comorbidities; early antifungal therapy and catheter removal may reduce it.

Pharmacodynamics of the Orotomides against Aspergillus fumigatus: New Opportunities for Treatment of Multidrug-Resistant Fungal Disease.

F901318 is an antifungal agent with a novel mechanism of action and potent activity against Aspergillus spp. An understanding of the pharmacodynamics (PD) of F901318 is required for selection of effective regimens for study in phase II and III clinical trials. Neutropenic murine and rabbit models of invasive pulmonary aspergillosis were used. The primary PD endpoint was serum galactomannan. The relationships between drug exposure and the impacts of dose fractionation on galactomannan, survival, and histopathology were determined. The results were benchmarked against a clinically relevant exposure of posaconazole. In the murine model, administration of a total daily dose of 24 mg/kg of body weight produced consistently better responses with increasingly fractionated regimens. The ratio of the minimum total plasma concentration/MIC (Cmin/MIC) was the PD index that best linked drug exposure with observed effect. An average Cmin (mg/liter) and Cmin/MIC of 0.3 and 9.1, respectively, resulted in antifungal effects equivalent to the effect of posaconazole at the upper boundary of its expected human exposures. This pattern was confirmed in a rabbit model, where Cmin and Cmin/MIC targets of 0.1 and 3.3, respectively, produced effects previously reported for expected human exposures of isavuconazole. These targets were independent of triazole susceptibility. The pattern of maximal effect evident with these drug exposure targets was also apparent when survival and histopathological clearance were used as study endpoints. F901318 exhibits time-dependent antifungal activity. The PD targets can now be used to select regimens for phase II and III clinical trials.IMPORTANCE Invasive fungal infections are common and often lethal. There are relatively few antifungal agents licensed for clinical use. Antifungal drug toxicity and the emergence of drug resistance make the treatment of these infections very challenging. F901318 is the first in a new class of antifungal agents called the orotomides. This class has a novel mechanism of action that involves the inhibition of the fungal enzyme dihydroorotate dehydrogenase. F901318 is being developed for clinical use. A deep understanding of the relationship between dosages, drug concentrations in the body, and the antifungal effect is fundamental to the identification of the regimens to administer to patients with invasive fungal infections. This study provides the necessary information to ensure that the right dose of F901318 is used the first time. Such an approach considerably reduces the risks in drug development programs and ensures that patients with few therapeutic options can receive potentially life-saving antifungal therapy at the earliest opportunity.

Changes in the distribution of colonising and infecting Candida spp. isolates, antifungal drug consumption and susceptibility in a French intensive care unit: A 10-year study.

Monitoring fungal ecology and resistance to antifungal agents within intensive care units (ICU) is essential for the management of invasive fungal infections. Therefore, a retrospective descriptive study was carried in the ICU of Nimes University Hospital, France, from 2007 to 2016. As the majority of invasive fungal infections in ICU are caused by Candida species, the study objectives were to describe Candida species distribution, to assess candidaemia incidence and to monitor the antifungal drug susceptibility of Candida isolates and the consumption of antifungal agents. Among the recorded invasive Candida infections (n=244), 43% were intra-abdominal and 22% bloodstream infections. Candida albicans was the most frequent species (55.8%), followed by Candida glabrata (14.1%), Candida tropicalis (10%), Candida parapsilosis (8%) and Candida krusei (5.3%). Candidaemia incidence was 4.49 per 1000 admissions. The mean consumption of antifungal agents was of 170.5 defined daily doses (DDD) for 1000 hospital days (HD) per year. Changes in antifungal drug consumption were observed, with an increased use of echinocandins (from 17.96 DDD/1000 HD in 2007 to 48.76 DDD/1000 HD in 2016), and the total treatment cost tripled during the study period. No significant change in fungal ecology or in the emergence of resistant species was observed; indeed, only 1.1% of isolates presented an unusual resistance to antifungal agents.

Fatal Cases of Bloodstream Infection by Fusarium solani and Review of Published Literature.

Fusarium species are ubiquitously present in environment and are well known as human pathogens with high mortality rate in immunocompromised patients. We report here two cases where immunocompromised patients developed fatal bloodstream infections by this organism. Isolates were further identified by ITS1 region sequencing which confirmed them as Fusarium solani. Antifungal susceptibility testing was done following CLSI M38-A2 guidelines to amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, caspofungin, and micafungin. Both patients had a fatal outcome and expired of septic shock. Therefore, identification up to species level is of utmost importance as that helps in directing the management of the patient thereby leading to a favourable outcome.

Epidemiology, clinical characteristics, and outcome of candidemia in a tertiary referral center in Italy from 2010 to 2014.

PURPOSE: We evaluated the epidemiology, clinical characteristics and outcome of candidemia in a single institution from 2010 to 2014. METHODS: A retrospective observational study of all cases of candidemia was carried out at a University Hospital in Central Italy including five intensive care units (ICUs), 11 medical and 11 surgical wards. Data regarding demographic characteristics and clinical risk factors were collected from the patient's medical records. Antifungal susceptibility testing was performed and MIC results were interpreted according to species-specific clinical breakpoints. RESULTS: A total of 270 episodes of candidemia were identified. Overall incidence rate was 1.5 episodes/1000 hospital admissions. Although Candida albicans represented the most commonly isolated species, its percentage significantly decreased from 68 to 48 % (p = 0.040). The overall 30-day mortality was 35 %. The variables independently associated with a significant higher risk of mortality were: older age; being hospitalized in ICU or in medical wards vs surgical wards; being infected with C. albicans vs other species; the occurrence of septic shock, pneumonia and acute renal failure; the presence of a solid organ tumor or a chronic pulmonary disease. Conversely, an appropriate treatment was confirmed to be significantly associated with a lower risk of mortality. The overall resistance was low and it was noted only among triazoles. CONCLUSIONS: Our study shows that candidemia is a significant source of morbidity and mortality. The identification of risk factors associated with mortality along with the knowledge of local susceptibility may lead to a better management in terms of preventive and therapeutic measures.

Effects of amphotericin B on Aspergillus flavus clinical isolates with variable susceptibilities to the polyene in an experimental model of systemic aspergillosis.

OBJECTIVES: The aim of the present study was to evaluate the effects of amphotericin B (AMB) on clinical isolates of Aspergillus flavus. METHODS: MICs of both standard AMB and liposomal AMB (L-AMB) were determined using a broth dilution method for seven isolates of A. flavus. AMB MICs were also determined using the Etest. The activity of the polyene was then investigated in a murine model of systemic aspergillosis in which animals were infected intravenously, treated intravenously with several doses of the polyene (1-10 mg/kg/day) and observed for survival. RESULTS: Broth dilution AMB, broth dilution L-AMB and Etest AMB MICs ranged from 0.5 to 2.0 mg/L, 0.06 to >16 mg/L and 1.0 to >32 mg/L, respectively. There were two isolates for which all doses were effective at prolonging the survival. Their AMB MICs were ≤1.0 mg/L, regardless of the method/drug formulation utilized for testing. There were four isolates for which no regimen was effective. Their broth dilution AMB, broth dilution L-AMB and Etest AMB MICs ranged from 1.0 to 2.0 mg/L, 0.06 to >16 mg/L and 2.0 to >32 mg/L, respectively. There was one isolate for which only L-AMB given at 10 mg/kg/day was effective; broth dilution MICs of AMB and L-AMB were 0.5 mg/L, while the Etest MIC of AMB was 2.0 mg/L. CONCLUSIONS: Our data indicate that not all isolates of A. flavus should be considered resistant to AMB. The Etest represented the in vitro method that best correlated with the experimental infection. Finally, a clinical isolate showing an MIC ≥2.0 mg/L may be reasonably considered resistant in vivo to any dose/formulation of the polyene.

Susceptibilidad in vitro de candida spp: aisladas de la cavidad oral de pacientes VIH/Sida a itraconazol, clotrimazol y ketoconazol / In vitro susceptibility of candida ssp: isolated fromthe oral cavity of HIV/AIDS patientes to itraconazole, clotrimazole and ketoconazole

La candidiasis orofaríngea (COF) permanece como una de las principales infecciones oportunistas en pacientes infectados con el virus de la inmunodeficiencia humana (VIH) y con el síndrome de inmunodeficiencia adquirida (sida), y aunque su incidencia ha disminuido con la introducción de la terapia antirretroviral de alta eficacia, continúa siendo una afección característica en estos pacientes. En el presente trabajo se realizó un estudio de susceptibilidad in vitro mediante la metodología del CLSI, frente a itraconazol, ketoconazol y clotrimazol de 144 aislamientos clínicos de Candida, aisladas de la cavidad oral de pacientes infectados con el VIH/sida con cuadros clínicos de COF. La identificación de los aislamientos demostró que más del 90% pertenecían a Candida albicans. Al determinar el patrón general de susceptibilidad frente a los azoles estudiados mediante el método de microdilución en caldo del documento M27-A2 del Clinical and Laboratory Standard Institute, C. albicans exhibió valores de concentración mínima inhibitoria (CMI) en un rango de 0,01 a 8µg/mL para el itraconazol y el ketoconazol y de 0,01 a 2 g/mL para el clotrimazol. Sólo el 2,1 % de los aislamientos mostró franca resistencia frente al itraconazol, en tanto que el 3,5 % quedó clasificado dentro de la categoría “susceptible dosis-dependiente” para este triazol. La mayoría de los aislamientos de C. albicans mostraron valores de CMI frente al ketoconazol y al clotrimazol menores a 0.06 g/mL, siendo de un 96,9% (129 aislamientos) y de un 97,7% (129 aislamientos), respectivamente. El clotrimazol tuvo una mejor actividadin vitro comparado con los restantes azoles frente a los aislamientos estudiados. Candida spp. Mostró una elevada sensibilidad in vitro a los azoles estudiados. Se hace necesario continuar realizando estudios epidemiológicos para determinar los patrones de susceptibilidad y tasas de resistencias frente a los agentes...

The oropharyngeal candidiasis (OFC) remains as one of the principal opportunistic infections in patients infected with the human immunodeficiency virus (HIV) and with the acquired immunodeficiency syndrome (aids), and although his incidence has declined with the introduction of the highly active anti-retroviral therapy (HAART), remains as a typical complaint in these patients. A study of antifungal in vitro susceptibility testing, following the CLSI methodology, was realized against itraconazole, ketoconazole and clotrimazole of 144 clinical isolations of Candida, isolated from the oral cavity of patients infected with HIV/aids, with clinical pictures of OFC. The isolation’s identification, demonstrated that more than 90% belonged to Candida albicans. The determination of the general pattern of susceptibility, following the document M27-A2 of the Clinical and Laboratory Standard Institute, against to the studied azoles by means of the method of microdilution in liquid medium, show that the majority of C. albicans isolates showed values of MIC against ketoconazole and clotrimazole lower than 0.06 g/mL, representing a 96,9% (129 isolations) and a 97,7% (129 isolations), respectively. C. albicans exhibited the widest range of minimal inhibitory concentration (MIC). Only 2.1% of the isolations showed resistance against to itraconazole, while 3.5 % remained classified in the category “sensible dose - dependent” for this triazole. The majority of the strains showed values of MIC against ketoconazole and clotrimazole below 0.06 g/mL. The clotrimazole had a better in vitro activity compared with the remaining azoles opposite to the isolations. Candida spp. showed a high in vitro sensibility to the azoles studied. It becomes necessary the maintenance of epidemiologic studies for the determination of susceptibility patterns and of resistances rates against to the antifungal agents