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Poor outcomes of invasive candidiasis (IC) are associated with the difficulty in establishing the microbiological diagnosis at an early stage. New scores and laboratory tests have been developed in order to make an early therapeutic intervention in an attempt to reduce the high mortality associated with invasive fungal infections. Candida albicans IFA IgG has been recently commercialized for germ tube antibody detection (CAGTA). This test provides a rapid and simple diagnosis of IC (84.4% sensitivity and 94.7% specificity). The aim of this study is to identify the patients who could be benefited by the use of CAGTA test in critical care setting.

The in vitro antifungal activity of a new liposomal nystatin formulation (NISTL, Nyotran, Aronex Ltd., EE.UU.) was evaluated by a microdilution method with RPMI based on the M27A document of the National Committee for Clinical Laboratory Standards (NCCLS) against 22 isolates of Cryptococcus neoformans. This antifungal activity was compared with those of other seven antifungal agents, such as nystatin (NIST), amphotericin B deoxycholate, liposomal amphotericin B, amphotericin B lipid complex, amphotericin B colloidal dispersion, fluconazole, and itraconazole. NISTL was more active in vitrothan NIST, showing MIC values 2-3 fold smaller in 90% of the isolates. The results obtained suggest that this new formulation would be very helpful for the treatment of cryptococcosis.

Objetivos: Utilizar varios métodos que permiten la diferenciación entre Candida albicans y Candida dubliniensis en un intento de conocer si C. dubliniensis puede ser aislada de la cavidad oral de adolescentes con prótesis ortopédicas orales. Materiales y métodos: Se aislaron 12 cepas de género Candida procedentes de mucosa palatina y de soporte de prótesis de 12 pacientes adolescentes portadores de prótesis ortopédicas orales. Para la diferenciación entre C. albicans y C. dubliniensis se utilizaron varias pruebas fenotípicas (la asimilación de fuentes de carbono con el método comercial ID 32C, el crecimiento en agar glucosado de Sabouraud a 45 ºC, la producción abundante de clamidosporas en agar caseína, y la reactividad mediante inmunofluorescencia indirecta con un antisuero específico para C. dubliniensis) y la reacción en cadena de la polimerasa (PCR). El serotipado de C. albicans se realizó con el anticuerpo monoclonal B9E. Resultados: Los 12 pacientes estudiados presentaron una estomatitis protésica tipo 2 de Newton y en todos los casos se aislaron las mismas especies de la muestra de mucosa y de la de prótesis del mismo paciente. El CHROMagar Candida y la prueba de la filamentación en suero permitieron diferenciar los aislamientos que daban lugar a colonias de color verde y filamentaban de los que daban colonias violetas y no lo hacían. Unicamente el aislamiento del paciente 8 fue positivo con el antisuero específico para C. dubliniensis y produjo abundantes clamidosporas en agar caseína, mientras que ocho aislamientos no presentaron crecimiento a 45 ºC. La identificación de todos los aislamientos se consiguió con la prueba ID 32C, identificándose C. albicans en el 75% de los pacientes, C. glabrata en el 16,6% y C. dubliniensis en el 8,3%. La PCR con iniciadores específicos para el tipado de C. dubliniensis permitió la identificación del aislamiento del paciente 8 como C. dubliniensis genotipo 1. Conclusión: C. dubliniensis puede ser aislada de la cavidad oral de adolescentes con estomatitis asociada a prótesis ortopédicas y es posible, y técnicamente asequible, la diferenciación entre C. albicans y C. dubliniensis mediante la realización de pruebas como el ID 32C, la observación de abundantes clamidosporas en agar caseína, la reactividad con un antisuero específico para C. dubliniensis y la PCR. Objectives: Test several methods that allow the differentiation between Candida albicans and Candida dubliniensis, in an attempt to assess whether C. dubliniensis can be recovered from the oral cavity of teenagers wearing orthopedic oral prostheses. Material and Methods: Twelve Candida strains were isolated from the prosthesis as well as the palatal mucosa in contact with the dental prosthesis from 12 teenager patients wearing orthopedic oral prostheses. Differentiation between C. albicans and C. dubliniensis was achieved by a number of phenotypic tests (carbon assimilation by the commercially available ID 32C test, growth at 45ºC on Sabouraud glucose agar, abundant chlamydospore production on Casein agar, and reactivity with a C. dubliniensis antiserum) and the polymerase chain reaction (PCR). Serotyping of C. albicans was performed with monoclonal antibody B9E. Results: All 12 patients studied presented a Newton’s type 2 denture stomatitis and in every patient the same Candida species were isolated from the prosthesis and the palatal mucosa in contact with the dental prosthesis. CHROMagar Candida and the germ tube test allowed the differentiation of isolates giving green colonies and a positive germ tube test from those giving violet colonies and a negative germ tube test. Only the isolate from patient 8 was stained by the C. dubliniensis antiserum and showed abundant chlamydospore production on Casein agar. Eight isolates did not grow at 45ºC. Identification of all isolates was obtained by the ID 32C test. C. albicans was identified in 75% of patients, C. glabrata in 16,6% and C. dubliniensis in 8,3%. By using specific primers for typing C. dubliniensis, PCR allowed the identification of patient’s 8 isolate as C. dubliniensis genotype 1. Conclusion: C. dubliniensis can be isolated from the oral cavity of teenagers wearing orthopedic oral prostheses and it is possible and technically amenable, the differentiation between C. albicans y C. dubliniensis using the ID 32C test, the observation of abundant chlamydospore production on Casein agar, the reactivity with a C. dubliniensis antiserum and the PCR.

It has been previously shown (J. Schneider et al., Br. J. Cancer, 77: 1015-1020, 1998) that an antibody directed against Candida albicans proteins (C6) recognizes specifically a protein in human ovarian tumors. We have now performed an immunoscreening of a human cDNA library using this antibody and identified the antigen as Nup88, a protein localized preferentially at the nuclear membrane and probably implicated in nucleocytoplasmic transport. Our results show that Nup88 is strongly expressed in a series of human tumor cell lines compared with nontransformed cell lines at the RNA and the protein levels. Furthermore, we observed that in 76% of 21 ovarian tumors analyzed, the protein is also overexpressed in malignant tissue when compared with healthy adjacent tissue. Nup88 may, therefore, be considered as a putative marker for tumor growth and is probably related to increased cell cycling.

We evaluate test for the detection of antibodies against-Candida albicans by indirect immunofluorescence (Candida Spot-IF, BioMérieux, Lyon, France and a test developed in our laboratory to detect anti-germ tube antibodies) comparatively for the serodiagnosis of invasive candidiasis.A total of 121 sera from 62 patients were studied retrospectively. They were divided into two groups: group I included 71 sera from 28 patients with invasive candidiasis and group II, used as control, included 50 sera from 34 patients with non-invasive candidiasis or without evidence of infection by Candida.Eighty-two percent of group I samples presented anti-germ tube antibodies and 57% of the patients in this group were positive by the Candida Spot-IF test. Both techniques were negative in 5 patients. Five patients in group II showed false positive results by Candida Spot-IF and two of them presented anti-germ tube antibodies also. Both techniques presented a poor correlation (R2 = 0.159; p0.001). Detection of anti-germ tube antibodies showed a sensitivity of 82% and a specificity of 94% and Candida Spot-IF showed a sensitivity of 57% and a specificity of 85%. Detection of anti-germ tube antibodies in immunocompetent patients showed a sensitivity of 90% but it decreased to 62% in immunocompromised patients. With the Candida Spot-IF test the sensitivity was 70 and 25%, respectively.The detection of anti-germ tube antibodies was more sensitive and specific than detection of antibodies by the Candida Spot-IF test and it can be used for the serodiagnosis and follow up of patients with invasive candidiasis.

Albicans IDR is a ready-to-use medium containing a hexosaminic substrate that allows rapid and specific identification of Candida albicans. In this study, we have evaluated its performance using 330 pure cultures of yeast strains previously identified by conventional mycological methods. The test correctly identified all the Candida albicans strains tested (186 isolates), but there were 28 false-positive reactions after 48 h of culture incubation. The false-positive isolates corresponded to the species Candida tropicalis (13 strains), Trichosporon beigelii (12 strains), Cryptococcus neoformans (one strain), Candida lusitaniae (one strain) and Candida membranaefaciens (one strain). The sensitivity of the method was 100% and the specificity was 90.3% at 24 h and 86.6% at 48 h of incubation. Albicans IDR plate is a new, easy-to-perform and inexpensive method for C. albicans identification, and it could be used for direct isolation and identification of this species from clinical samples.

Candida pelliculosa Redaelli (syn. Hansenula anomala) was isolated from blood cultures of a patient with acquired immunodeficiency syndrome. The transient candidaemia was apparently associated with intravenous drug addiction. The isolate was identified by standard methods such as API 20 C Aux and 16 discs carbon auxanogram. The isolate was sensitive to amphotericin B, 5-fluorocytosine and ketoconazole. This organism adds to the growing list of Candida species associated with acquired immunodeficiency syndrome.