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Introduction: culture collections are responsible for providing the microbial resources for development of biological sciences. Storage in distilled water is one of the easiest and least expensive method for long-term fungal preservation., Objective: to evaluate the usefulness of this preservation method in fungal culture of Histoplasma and Cryptococcus., Methods: the preservation condition of the highest biological risk species from Histoplasma y Cryptococcus genera, included in the fungal culture collection of "Pedro Kouri" Institute of Tropical Medicine in Havana, was evaluated in this study. One hundred and two strains stored in distilled water, 92% of which had been preserved for more than 10 years, were analyzed., Results: the percentages of recovered strains from H. capsulatum, C. neoformans and C. gattii were 64.3%; 79.1% and 100% respectively. This method of preservation proved to be satisfactory for fungal culture in labs with limited financial resources. A web-based database with interesting information about the collection was made. The importance of strict compliance with the biosafety measures in these collections, particularly with high risk pathogens., Conclusions: preservation of fungal cultures in distilled water is a very useful method for laboratories with limited resources. Culture collections should be assumed as an essential activity in order to solve increasing challenges in the development of biomedical sciences.

Histoplasmosis, an infection caused by the fungus Histoplasma capsulatum, has been reported all over the world and is considered endemic in the American continent, including Cuba. This fungus grows on the soils contaminated with bird and bat excreta, where it produces a great number of microconidia that could cause the infection when they are inhaled. The clinical spectrum varies from asymptomatic infections to serious disseminated diseases involving one or many organ systems and affects mainly AIDS patients, patients with hematological neoplasias, transplant recipients or other immunosuppressed patients. The main risk groups include those individuals whose working activities make them be exposed to aerosols contaminated with H. capsulatum. Lab diagnosis is based on the microscopic observation, isolation and identification of the fungus in fluid or tissue samples of patients, and on specific antigen and antibodies detection. The molecular methods based on polymerase chain reaction have not been sufficiently defined, and they could be an important advance in the early diagnosis of this mycosis. Itraconazole is recommended for treatment of moderate, localized and chronic infection whereas amphotericin B is the drug of choice for disseminated and serious manifestations, particularly in its lipidic formulations. At present, histoplasmosis is considered one of the most important systemic mycoses in the Americas, and it is widely spread over all regions of Cuba.

Introduction: oropharyngeal candidiasis is an early marker of progression to AIDS in H1V-positive patients and an indicator of non-adherence of treatment or possible failure in patients undergoing anti-retroviral therapy., Objective: to determine the in vitro susceptibility to nystatin in Candida strains isolated from the oral cavity of HIV-positive patients, and to correlate the results with the response to treatment., Methods: a study of in vitro susceptibility to nystatin was conducted in 104 oral isolates from 97 HIV/AIDS patients, who participated as volunteers in a clinical trial to evaluate the response to four antifungal drugs. Fifty-eight of the 104 isolates were obtained before starting treatment and the remaining 46 at the end of therapy. Broth microdilution method was performed according to the document M27-A3 of the Clinical and Laboratory Standards Institute., Results: one hundred percent of the strains were susceptible to nystatin, with minimum inhibitory concentration (MIC) values of <16 microg/mL, regardless of the time of isolation and of the drug administered to patients. In the group of patients treated with nystatin, the MIC80 ranges (1-2 microg/mL), geometric mean and cumulative values of the drug against Candida albicans isolates before starting treatment were similar to those obtained against strains recovered at the end. Among the identified species, C. lusitaniae reached the highest absolute MIC value (4 microg/mL)., Conclusions: the correlation between the clinical evolution and the results of in vitro susceptibility tests was good in patients with a favorable outcome; however, it did not allow predicting possible treatment failure.

Introduction: Cryptoccosis--systemic mycosis caused by Cryptococcus species--has considerably raised its incidence in the last years, mainly associated with the human immunodeficiency virus infection. It has also been described in animals, but rare cases., Methods: a case of a female cheetah (Acinonyx jubatus) kept in the Nacional Zoo of Havana was presented. The animal came from South Africa. She began losing weight, and suffering asthenia, anorexia and breathing problems with abundant nasal secretion., Results: mycological testing of these secretions disclosed the presence of serotype B Cryptococcus gattii. Because of the origin and captive condition of the animal, it was believed that the infection had been latent for 16 months at least., Conclusions: up to the present, in Cuba, all clinical Cryptococcus isolates were C. neoformans var. grubii, so it is considered that the infection was caught in the country of origin of the female cheetah. This is the first C. gattii isolate in Cuba from an animal coming from South Africa where this fungus is endemic.

Introduction: histoplasmosis, an infection caused by Histoplasma capsulatum fungus, is considered as one of the main endemic infections in the American continent where there are frequent epidemic outbreaks. Most of the outbreaks have been associated to risky activities in bat-inhabited places. This paper presented two outbreaks of occupational acquired histoplasmosis occurred in La Habana province., Methods: one hundred and sixteen workers, who performed aerosol-generating tasks in caves, were studied. Samples from the cave soils were taken to assess the existence of the causal agent. Clinical and epidemiological data were gathered for the outbreak characterization., Results: the rates of infection for both outbreaks were 60 % and 78 % respectively. The patients aged 16 to 64 years; additionally, the onset of main clinical manifestations (fever, general malaise, cough, headache, loss of weight, and chest pain) ranged from 10 to 20 days. Histoplasmosis was microbiologically and serologically diagnosed whereas its source of infection was confirmed through H. capsulatum isolation in those places where extensive excavation work had been carried out, resulting in abundant aerosols for up to 21d periods. The similarity between the two outbreaks was the performance of aerosol-generating tasks in risky places without using appropriate safety devices., Conclusions: It is necessary to disseminate the existing preventive measures among the health care staff and the risky groups as well as the general population in order to prevent and take control of possible histoplasmosis outbreaks in the future.

In vitro antifungal susceptibility testing is really necessary at present in medical mycology laboratories. Minimal inhibitory concentration of 210 Candida yeast strains isolated from HIV/AIDS patients with oral lesions was determined to find out susceptibility to fluconazole and amphotericin B. A CLSI's M27A2 protocol-based dilution micromethod was used. C. albicans was predominant (62.4%)followed by C. glabrata, C. parapsilosis, and C. tropicalis. Regarding amphotericin B, the mode value and MIC50 were 0.125 microg/mL, which indicated the effectiveness of this drug in vitro conditions. Only C. krusei strain showed a minimal inhibitory concentration over 1 microg/mL. 8.1% of strains were resistent to fluconazole whereas 8.1% was dose-depending susceptible. The less susceptible species were C. krusei and C. glabrata. The achieved results laid the foundations for wider studies to be made in the Cuban context and indicated the need of keeping surveillance on the behaviour of clinical yeast isolates to antifungal drugs.

A study of 115 strains, which had been isolated from vaginal smears and identified at the beginning as Candida albicans, was conducted to find out if there was Candida dubliniensis in Cuba. The growth of those isolates that due to their morphological characteristics were identifified as either C. albicans or C. dubliniensis was checked up at 42 degrees in Sabouraud agar. C. albicans was the predominant species (88.69%). For the first time in Cuba, 13 C. dubliniensis strains were presumptively identified. The achieved results are of great benefit because they will contribute to the conduction of epidemiological and resistance studies to antifungicidal products.

A review was made on the collection of fungi cultures of "Pedro Kourí" Institute of Tropical Medicine" that was created in 1980 to give an answer to the increasing needs of the newly established laboratory of Mycology of that institution at that time. The collections of microbial cultures are more important every day as a way for the ex situ conservation of the microbial biodiversity. They are in charge of collecting, saving, identifying and preserving those strains of interest for biomedical research, teaching, industry, agriculture, etc. At present, the collection of the institute has a total of 262 strains from 81 species of fungi, actinomycetes and algae, all of them of interest for Medical Mycology. The main methods for the maintenance of the cultures have been the conservation in distilled water and freeze-drying, in additions to the periodical mincing in agar media, refrigeration and freezing. The service of reference and control of quality, the identification of strains, teaching, the taxonomic studies, and the safeguard, among others, are some of the main functions developed by this collection. Nowadays, the collections of fungus cultures must face the challenges represented by the emerging pathogenic fungi, as well as the incorporation of molecular techniques confirming the quality of the strain preservation methods. These collections should play an important strategic role in the preservation of the biodiversity, taking into account legal and biosafety aspects, too.

The obtention of antisera at the Mycology Laboratory of "Pedro Kouri" Institute of Tropical Medicine was proposed to allow the rapid identification of the varieties and serotypes of Cryptococcus neoformans, since it is very important from the clinico-epidemiological point of view to know them. By immunizing rabbits with formalized whole cells of the 4 serotypes of this yeast, it was possible to obtain antisera that were absorbed with cells of the heterologous serotypes. 3 antisera capable of differentiating the neoformans var. (anti AD) and its respective serotypes (anti-A and anti-D) were attained. This paper will contribute to the knowledge of the epidemiology of this important disease in the Cuban setting for being the first time that useful antisera are obtained in Cuba to identify the serotypes corrresponding to the neoformans variety, which is the main causal agent of criptococcosis.

A comparative study was conducted between the assimilation of D-proline and the growth on canavanine-glycine-bromothymol blue (CGB) medium used for the classification of the varieties of Cryptococcus neoformans. In the 86 studied strains, 100% of coincidence between both methods allowed to affirm that 95.34% corresponded to the neoformans var. and the rest (4.65%) to the gattii var. The results obtained corroborated that all the autoctonous clinical isolations up to the present correspond to the. neoformans var. and made possible to suggest the use of D-proline for the initial evaluation of strains, as an alternative and simple method that presented under these conditions high coincidence with the reference method (growth in CGB).

A study of 404 women that attended the Microbiology Laboratory of Ramón Gonzalez Coro Gynecoobstetric Hospital, in Havana City, was conducted aimed at identifying species of yeasts isolated from Pap smears, registering the signs and clinical symptoms and determining the risk factors associated with infection. The isolated yeasts were identified by the filamentation tests in serum, production of chlamydoconidia and carbohydrate assimilation. It was found that 138 (34.16%) of women had yeasts in the vagina. 3 genera were identified: Candida (88.49%). Trichosporon (10.79%) and Rhodotorula (0.72%). Pruritus and heat showed statistical significance (p < 0.01). Pregnancy, the use of IUD and the antibacterial therapy proved to be the most common risk factors in relation to the presence of Candida in the vagina.