Validation of an immunologic diagnostic kit for infectious vaginitis by Trichomonas vaginalis, Candida spp., and Gardnerella vaginalis Arsenio Betancourt Bravo a, ⁎ , Lilian Sánchez Miranda a , Octavio Fernández Lima a , Alexandra Villoch Cambas a , Maite Lorenzo Hernández a , Juan Manuel Álvarez b a National Center for Agricultural Health (CENSA), carretera de Jamaica y Autopista Nacional, San José de la Lajas, La Havana PC32700, Cuba b Faculty of Chemical Sciences, Department of Microbiology, Benemérita Universidad Autónoma de Puebla, Puebla PC 72570, Mexico Received 17 July 2008; accepted 20 November 2008 Abstract FemPure is a kit for the rapid diagnosis of vaginitis by Trichomonas vaginalis, Candida spp., and Gardnerella vaginalis, based on aggregation of latex particles joined to specific antibodies. The validation of the method involved the parameters specificity, detection limit, robustness, clinical sensitivity, and clinical specificity. Also, samples analyzed in parallel by the validated test and other recognized tests conducted by external laboratory were included. The method was specific for the 3 infectious agents, and no cross-reaction with other microorganisms usually present in vaginal exudates. The detection limit ≥1 × 10 6 CFU/mL for Candida albicans and G. vaginalis avoids the detection of concentrations considered normal flora, whereas T. vaginalis was detected until 1 × 10 5 cells/mL. Values of clinical sensitivity ≥80% and clinical specificity ≥90% and concordance ≥90% were found between samples evaluated in parallel by different methods. Robustness showed that the test can be used in laboratories with different management systems; its simple implementation without equipment allows the use in primary health care areas. © 2009 Elsevier Inc. All rights reserved. Keywords: Validation; Infectious vaginitis; Diagnostic test; Trichomonas vaginalis; Candida albicans; Gardnerella vaginalis 1. Introduction Vaginal infections are the most common gynecologic health problem in primary care. The prevalence of infectious vaginitis in symptomatic women exceeds 50%; Gardnerella vaginalis associated to bacterial vaginosis is the most frequently diagnosed agent, followed by Candida albicans and, to a lesser extent, Trichomonas vaginalis (Egan and Lipsky, 2000; Owen, 2004). Bacterial vaginosis is a disruption of vaginal flora characterized by a lack in lactobacillus and increase in the quantity of anaerobic bacteria where G. vaginalis is found in nearly 100% of cases. Based on the G. vaginalis detection in clinical relevant levels by DNA hybridization, this test has been proven to be useful for the diagnosis of bacterial vaginosis, which is comparable with Gram stain method and the more sensitive diagnostic tests for detection and identification of symptomatic vaginitis/vaginosis than the conventional clinical examination and wet mount testing (Brown et al., 2004; Witt et al., 2002). Microscopic examination of the saline fresh mounts is somewhat subjective; correct diagnosis can be elusive, complicating treatment and making it difficult to determine accurate prevalence rates (Thomason et al., 1992). Indeed, several studies using this method to establish the prevalence of the most common infectious agents for vaginitis have shown widely varying results, which may in part actually be due to inaccurate diagnoses (Hart 1993; Konje et al., 1991; Mirza et al., 1983; Ray et al., 1989; Tohill et al., 2004). Immunologic tests, on the other hand, are simple to perform, generate immediate results, and should be useful for prevalence studies because of the homogeneity of the method. The immunologic kit FemPure™ (latex agglutination test [LAT]) is a diagnosis method that in 3 min detects simultaneously T. vaginalis, Candida spp., Available online at www.sciencedirect.com Diagnostic Microbiology and Infectious Disease 63 (2009) 257 – 260 www.elsevier.com/locate/diagmicrobio ⁎ Corresponding author. CENSA carretera de Jamaica y Autopista Nacional, San José de las Lajas, La Havana, Cuba. Tel.: +53-47-863014; fax: +53-47-861104. E-mail address: arsenio@censa.edu.cu (A.B. Bravo). 0732-8893/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.diagmicrobio.2008.11.010