Pathogenicity of Hansenula anomala in model of immunocompromised mice.

Systemic infections caused by opportunistic fungi have shown an increased frequency in the past 10 years, particularly in immunocompromised patients. Hansenula anomala is an ascosporogenous yeast of the Ascomycetes class found in the skin, throat, and digestive tract transient normal flora. This study was conducted to compare the pathogenicity of H. anomala and Candida albicans in a model of immunocompromised mice. Thirty-eight Swiss mice were divided into two groups as follows: 30 animals received an intraperitoneal (i.p.) injection of cyclophosphamide (200 mg/kg) four days before the induction of infection with H. anomala (1 x 10(6) yeasts/mL), and 8 animals received 100 mg/kg of cyclophosphamide at 3-day intervals during 3 weeks before inoculation of 1 x 10(7) yeasts/mL. All animals were treated with amoxicillin/clavulanic acid (40 mg/kg) four days before induction of infection. A group of mice inoculated with C. albicans (ATCC 64548) served as control. Tissue samples from the lung, spleen, liver, and kidney for histological and mycologic studies were obtained at necropsy. In each animal, the number of viable yeasts per gram of kidney was determined. The organs most frequently infected by H. anomala were the kidneys and the liver (20%), and the lung (10%). However, in conditions of sustained immunosuppression, H. anomala was found in 65.5% of the organs examined. It is concluded that in an experimental model of immunocompromised mice, the pathogenicity of H. anomala was low.

[Minimal inhibitory concentrations of Candida species to five antifungals by using the reference dilution micromethod and the E-test.]. / Concentraciones mínimas inhibitorias de levaduras a cinco antifúngicos utilizando un micrométodo de dilución estandarizado y el E-test.

It is accepted that the frequency of candidosis has increased during the last decade, specially in hospitalized patients. The more frequent use of azole antifungals and the recognition of isolates of Candida sp resistant to these and other drugs such as 5-fluorocytosine constitute a great need for a reproducible and useful C. albicans in vitro susceptibility testing method for monitoring antifungal therapy in clinical mycological laboratories. The E-test is a novel agar diffussion technique for testing the susceptibility of yeasts against a defined continous gradient of drug and could be used by most clinical laboratories. In this study the E-test and the NCCLS reference microbroth method (M27-P guidelines) were used to determine the MICs of amphotericin B, 5-flucytosine, itraconazole, fluconazole and ketoconazole for 50 clinical isolates of Candida albicans, Torulopsis glabrata, C. tropicalis and Hansenula anomala and five reference ATCC strains. The main purpose of the study was to compare the results obtained by the two methods. In general good agreement (+/- 1 dilution) was otained between both methods, despite differences observed for some species-antifungal combinations in which the MICs were lower by the E-test than by the microbroth method. MICs for C. albicans and T. glabrata to amphotericin B were < 0.50 microg/mL. Two isolates of C. albicans and two others of H. anomala, showed MIC < 8 microg/mL for 5- flucytosine. All isolates of T. glabrata and 40% of C. albicans showed MICs > 16 microg/mL for fluconazole. The results of this study indicate that E-test is an alternative for susceptibility testing to the NCCLS reference method. Because its simplicity it seems to be an easier test for routine clinical laboratories.

Identification of the perfect state of Cryptococcus neoformans from 195 clinical isolates including 84 from AIDS patients.

Filobasidiella neoformans is the teleomorphic state of Cryptococcus neoformans and it is a heterothalic. The purpose of this study was to establish the proportions of each mating types (a, alpha) from among 195 strains of C. neoformans isolated from clinical material. The culture medium used was sunflower agar. Cultures were incubated at 20-22 degrees C for 15 days and observed periodically for one month. Non-reactive strains were mated several times with different reactive strains. Under these conditions 96.8% of the strains were found to be reactors. Among both varieties of C. neoformans, mating type alpha was found to have the highest frequency of 95% in the variety neoformans and 84% in the variety gattii. These results showed a higher reactivity in comparison with other investigators. This difference could be due to the medium used or to repeated mating with different reactive tested strains.

Renal infection due to Absidia corymbifera in an AIDS patient.

A case of renal zygomycosis due to Absidia corymbifera in an heroin addict suffering from AIDS (phase IV C2) is described. Diagnosis was by histopathology after nephrectomy, but A. corymbifera was isolated several times from urine and from the exudate from a fistula in the surgical wound. After amphotericin B treatment (1.5 g overall dose) clinical cure and negative cultures were obtained. No relapses were observed until death 1 year later from Pneumocystis carinii pneumonia.

Incidence of dermatophytoses in rabbit farms in Catalonia, Spain, and its repercussion on human health.

Over the past decades there has been an important increase in the incidence of dermatophytoses in humans as a result of contact with animals, although etiological agents can vary as can the animals transmitting the disease. A large-scale study was carried out in 220 farms raising rabbits for consumption. Most of the farms (85%) were located in the autonomous community of Catalonia (Spain). Mycological studies showed that 79.5% of the rabbits were infected with Trichophyton mentagrophytes var. granulosum. Microsporum canis was isolated in only two animals, which had been imported from France. Healthy animal carriers were detected in 3.2% of the apparently non-infected farms. T. mentagrophytes were also found in samples taken from rabbits' nests and from the surrounding environment of the two infected farms. In a survey carried out among the staff responsible for the care of the animals, 77% of those working on infected farms suffered or had suffered dermatophytic lesions. This was confirmed in 8 out of 10 cases sampled. Attention is drawn to the high incidence of dermatophytoses in rabbits on farms and the importance of T. mentagrophytes as the etiological agent of tinea in people in close contact with infected animals.

Non-traumatic topical treatment of onychomycosis with urea associated with bifonazole.

The need for a topical, non-traumatic treatment for onychomycoses of different etiologies has led to a search for increased effectiveness by associating products which have different and complementary effects, as is the case of the keratoplastic and broad-spectrum antifungal agents. Using a 40% urea and 1% bifonazole cream, 42 nails with fungal infections (28 patients) were treated until the infected area softened and could be removed, after which 1% bifonazole cream was applied. After a 6 to 12 month follow-up, the treatment success rate has been 93.8% for fingernails and 88.5% for toenails. The cultures became negative within 3 weeks after starting therapy with urea and bifonazole. Tolerance was good and it was not necessary to stop treatment in any patient. The topical, combined use of urea and bifonazole is a good alternative in the treatment of onychomycoses of different etiologies, provided that strict compliance by the patient is ensured, and that the application instructions are followed correctly.

[Distribution of serotypes A and B of Candida albicans in 502 strains isolated from pathological specimens]. / Distribución de los serotipos A y B de Candida albicans en 502 cepas aisladas de productos patológicos.

BACKGROUND: Candida albicans is distributed in at least two serological groups (A and B) depending on its antigenic structure. These characteristics have been used to investigate the epidemiology of candidiasis. No information is available in this country about the distribution of these serotypes in a general population of patients with candidiasis of different localizations. The aim of the present study was to correlate the frequency of C. albicans serotypes with the origin of the clinical samples. METHODS: In 502 strains of C. albicans isolated from pathological products, serotype was evaluated by means of a latex agglutination test with polyclonal monovalent antisera. A statistical analysis was carried out to investigate whether there was any relationship between the serotype frequency and the origin of the strains. RESULTS: The serotype A of C. albicans represented 78% of all isolates. However, there was a significantly higher relative frequency of serotype B in vaginal and oropharyngeal samples. No differences were found in isolates from AIDS patients. CONCLUSIONS: The serotyping method should be considered a contribution, even if limited, to the knowledge of the epidemiology of Candida albicans infections.

[In vitro sensitivity to 5-fluorocytosine and amphotericin B of yeasts of the Candida genus isolated in Barcelona]. / Sensibilidad in vitro a la 5-fluorocitosina y anfotericina B de levaduras del género Candida aisladas en Barcelona.

In 200 strains of Candida sp, 38.5% were found to have intermediate sensitivity or to be resistant to amphotericin B and/or 5-fluorocytosine by the agar diffusion method. When the minimal inhibitory concentrations of these strains were measured, only 7.8% were resistant to amphotericin B and 2.8% to 5-fluorocytosine. The species with the highest levels of resistance were C. parapsilosis, C. tropicalis and Torulopsis glabrata. Candida albicans did not show resistance to 5-fluorocytosine.

Susceptibility of Candida species to cilofungin (LY-121019).

The antifungal activity of a new semi-synthetic lipopeptide named cilofungin (LY-121019) was studied in vitro on 102 strains of Candida and Torulopsis glabrata. A standardized protocol for susceptibility testing by means of a microtiter Sabouraud broth dilution was used. The minimal inhibitory concentrations of cilofungin for C. albicans (N = 50) ranged from 0.039 to 5.0 micrograms/ml with a geometric mean of 0.47 micrograms/ml. The same results were obtained with C. tropicalis but one strain showed higher resistance (40 micrograms/ml) suggesting an Eagle effect. The MIC for T. glabrata ranged from 5.0-40.0 micrograms/ml. C. parapsilosis and C. krusei were less susceptible (5.0-40.0 micrograms/ml). These results indicate that cilofungin exhibits a potent inhibitory action on C. albicans and C. tropicalis. This effect was lower against the other species of Candida and T. glabrata studied.