ABSTRACT
We have compared two diagnostic systems, API-ID32C (bioMerieux) and VITEK-2ID-YST (bioMerieux), in their ability to diagnose 50 clinical isolates of Candida dubliniensis. API identified 48 isolates and VITEK-2 identified 33 of the 50 isolates. Lactic acid assimilation showed highly dispersed results with API, being of special importance, since this test is one of the four that makes it possible to differentiate C. dubliniensis from C. albicans. The detection of one enzyme, Phosphate-4MU, was always positive with VITEK-2 when it should have been negative. Overall, API ID 32C obtained better results than VITEK-2. However, the latter is simpler to use and has a greater database.
Subject(s)
Candida/classification , Mycological Typing Techniques/methods , Automation , Candidiasis/microbiology , Humans , Reproducibility of Results , Sensitivity and Specificity , Species SpecificityABSTRACT
INTRODUCTION: Two tests for the detection of antibodies to Candida albicans germ tubes in patients with invasive candidiasis were compared: a new commercially available test (Candida albicans IFA IgG) and the indirect immunofluorescence test generally used for this purpose. METHODS: With the use of two indirect immunofluorescence tests, retrospective study was done on 172 sera from 51 patients classified into two groups: Group I included 123 serum samples from 32 patients with invasive candidiasis, and Group II, the control, included 49 serum samples from 19 patients with no evidence of Candida infection. RESULTS: In Group I, 84% of patients presented anti-germ tube antibody titers >or= 1:160 by the Candida albicans IFA IgG test and 78.1% of patients were positive by the generally used test. There was a high correlation between the two tests (R2 =0.9512 by patients; R2 = 0.8986 by sera). When a titer value of >or= 1:160 was used as cutoff, the Candida albicans IFA IgG test showed a sensitivity of 84.4% and a specificity of 94.7%, whereas the traditional test showed a sensitivity of 78.1% and a specificity of 100%. CONCLUSIONS: The commercially available Candida albicans IFA IgG test is similar to the test generally used for the detection of antibodies to C. albicans germ tubes and provides faster and easier diagnosis of invasive candidiasis in the clinical microbiology laboratory.
Subject(s)
Antibodies, Fungal/blood , Candida/immunology , Candidiasis/diagnosis , Fluorescent Antibody Technique, Indirect , Fungemia/diagnosis , Reagent Kits, Diagnostic , Adolescent , Adult , Aged , Antigens, Fungal/immunology , Candida/classification , Candida albicans/immunology , Candidiasis/microbiology , Disease Susceptibility , Female , Fungemia/microbiology , Humans , Male , Middle Aged , Mycelium/immunology , Postoperative Complications/diagnosis , Postoperative Complications/microbiology , Retrospective Studies , Sensitivity and Specificity , Serologic Tests/methodsABSTRACT
INTRODUCCIÓN. Se comparan dos pruebas para detectar anticuerpos antimicelio en pacientes con candidiasis invasiva: una nueva técnica comercializada (Candida albicans IFA IgG) y la técnica de inmunofluorescencia indirecta tradicionalmente empleada para la detección de anticuerpos contra la fase micelial de C. albicans (anticuerpos antimicelio). MÉTODOS. Mediante dos técnicas de inmunofluorescencia indirecta se estudiaron retrospectivamente un total de 172 sueros de 51 pacientes clasificados en dos grupos: el grupo I incluía 123 sueros de 32 pacientes con candidiasis invasiva y el grupo II, utilizado como control, comprendía 49 sueros de 19 pacientes sin evidencia de infección por Candida. RESULTADOS. El 84,4 por ciento de los pacientes con candidiasis invasiva (grupo I) presentaron títulos de anticuerpos antimicelio 1:160 con la prueba Candida albicans IFA IgG, mientras que el 78,1 por ciento lo hicieron con la técnica tradicional.Ambas técnicas presentaron una alta correlación al ser comparadas entre sí (R2 0,9512 por pacientes; R2 0,8986 por sueros). Utilizando un título de corte de anticuerpos antimicelio 1:160 para el diagnóstico de la candidiasis invasiva, la prueba Candida albicans IFA IgG presentó una sensibilidad del 84,4 por ciento y una especificidad del 94,7 por ciento, mientras que la técnica tradicional presentó una sensibilidad del 78,1 por ciento y una especificidad del 100 por ciento. CONCLUSIÓN. La prueba comercializada Candida albicans IFA IgG es muy similar a la prueba tradicionalmente empleada para la detección de anticuerpos antimicelio, permitiendo un diagnóstico más rápido y sencillo de la candidiasis invasiva en los laboratorios de microbiología hospitalarios (AU)
