First characterization of Candida albicans by random amplified polymorphic DNA method in Nicaragua and comparison of the diagnosis methods for vaginal candidiasis in Nicaraguan women

Abstract

The genital candidiasis is one of the pathogenic demonstrations of yeast. Candida albicans is the most frequent species; it is usually isolated in 85 to 90% from the vaginal mycoses (Odds et al. 1988).Vaginal candidiasis affects females at least once during their lifetime, at an estimated rate of 70 to 75%, of whom 40 to 50% will experience a recurrence (Sobel 1999).In Nicaragua, we know very little about the prevalence and incidence of vaginal candidiasis and no study of the biology of C. albicans has been carried out. In this country, diagnosis of vaginal candidiasis is mainly based on the clinical presentation. Laboratories of the hospitals and health centres (peripheral laboratories) carry out only the microscopic diagnosis from the vaginal fluid. In the laboratory of the National Centre of Diagnosis and Reference of Nicaragua (CNDR), the yeast identification is based on the observation of the microscopic aspects, culture and biochemical tests.Most of the genetic studies revealed that C. albicans is predominantly clonal (Pujol et al. 1993, Helstein et al. 1993, Lockhart et al. 1995, Xu et al. 1999. Some authors have proposed that clonal propagation with a remaining capacity of recombination, shape the population structure of C. albicans (Caugant & Sandven 1993, Gräser et al. 1996, Tibayrenc 1997 Southern blot hybridization with the moderately repetitive DNA Ca3 probe, not only clustered moderately related isolates in a similar fashion but also afforded similar levels of resolution of microevolution within a clonal population.The goal of this study was to use the RAPD method to examine the patterns of yeast genetic diversity among women with vaginitis from a single geographic area. We were specifically interested to know the frequency of yeast in vulvovaginal secretions. We also compared the conventional methods of yeast diagnosis from vaginal samples used in Nicaragua and yeast culture method. MATERIALS AND METHODSThe vaginal swabs were taken from 106 women exhibiting symptoms of vulvovaginitis, who were attended in the outpatient ward of the CNDR in Managua, Nicaragua, between June and August 1997. Swabs were processed by the method routinely used for the detection of germinated yeast pathogens: microscopic examination of wet mount, with a 10% potassium hydroxide (KOH) preparation, and the Gram's stain. Samples were inoculated into Sabouraud-glucose agar, supplemented with chloramphenicol, and were incubated at 37°C for 48 h. For identification of C. albicans, isolates were placed in foetal calf serum for 4 h to test for the production of germ tubes and were incubated on Rice-Agar-Tween (RAT ® ) BioMérieux Laboratories, France for 48 h to induce chlamydospores. All yeast isolates were preliminary identified to the species level according to the CHROMagar Albicans® Test (Mycoplasme International, Toulon, France). This medium contains a chromogene substrate for immediate identification of C. albicans (green), C. tropicalis (metallic blue), C. glabrata (pink) and C. krusei (pale pink). Yeast species were conf...

Molecular Epidemiology and In Vitro Antifungal Susceptibility of Candida Isolates from Women with Vulvovaginal Candidiasis in Northern Cities of Khuzestan Province, Iran

“…Vulvovaginal candidiasis is more prevalent in this age group probably due to the excessive use of contraceptive methods, such as intrauterine devices and oral contraceptive pills. In agreement with previous studies in Iran and other countries (2,24,25,(29)(30)(31), C. albicans was the most common pathogen isolated from VVC patients in the present study. However, in a study by Mohanty et al (32), C. glabrata was the main species isolated from VVC patients.…”

Study of Virulence Markers and Antifungal Susceptibility by Vitek-2 in Various Candida Species Isolated from Cases of Vulvovaginal Candidiasis

“…Rates of isolation of C. dubliniensi shave been reported to range between 0.17% to 29.5%, while that of C. krusei from 3% to 15.7%. 11,12,15,19 Cultural, ethnic and epidemiological differences may influence the isolation rate of different yeast from vulvovaginitis samples. However, it goes beyond doubt that there is need to speciate Candida, be it for epidemiological purpose or from point of view of ensuring institution of the correct antifungal.…”

Candidosis vaginal. Segunda parte:diagnóstico, tratamiento y situación de algunos países latinoamericanos

“…Con excepción de C. glabrata, el resto de las especies asociadas a candidosis pueden formar seudomicelios y C. albicans y C. dubliniensis además son formadoras de hifas. C. glabrata es conocida por su resistencia natural a los antimicóticos azólicos mientras que cepas de otras especies, entre ellas C. albicans, C. krusei, C. parapsilosis, C. guilliermondii, C. famata, C tropicalis muestran variabilidad ante los azólicos [1,22,[28][29][30][31][32][33][34][35].…”