MOLECULAR CHARACTERIZATION AND PHYLOGENY OF CANDIDA SPECIES ISOLATED FROM HIGH VAGINAL SWAB SAMPLES AMONG PATIENTS PRESENTING WITH VULVOVAGINAL CANDIDIASIS IN PORT HARCOURT, NIGERIA
*Azike C. A., Nwokah E. G. and Abbey S. D.
ABSTRACT
Vulvovaginal candidiasis with the attendant morbidities remains a major reason for female visit to STI clinics. However, proper diagnosis has been a challenge. This study was conducted to carry out molecular characterization and phylogeny of Candida species from vulvovaginal patients. One hundred and eighty (180) high vaginal swab specimens from female patients presenting with vulvovaginal candidiasis, attending University of Port Harcourt Teaching Hospital were collected and cultured using standard procedures. The positive isolates were subcultured on the Sabouraud Dextrose Agar slant while DNA was extracted for molecular analysis. Internal transcribed spacer (ITS) gene extracted was amplified, product resolved on 1.5% agarose gel to measure the base pairs and then sequenced, edited and aligned with MEGA 6.0 to infer Phylogeny. A total of 72 positive isolates of Candida were assessed in this study. The result obtained from culture medium inoculation showed the Candida species were 72(40%), and non-Candida species were 108(60%). The positives isolates were subjected to germ tube test and the result showed that 24(33.3%) were Candida albicans, 24(33.3%) were non-albicans species and 24(33.3%) were unidentified. However, molecular analysis revealed 33(45.8%) C.albicans, 36(50%) non-albicans species which consists of C.glabrata, C. parapsilosis, C.tropicalis, C.Krusei (Pichia kudriavzevii), Candida akabenensis and Filobasidium uniguttulatum; and 4.2% unidentified species. Most species phenotypically identified as C.tropicalis were genetically characterized as C.albicans. All the unidentified species by germ tube test were molecularly identified and the only isolate unidentified using molecular tool was characterized as C.albicans by conventional technique. Hence there was significant difference between results obtained from conventional method and that from molecular analysis. Molecular technique in this study was more discriminatory than routine conventional approach.
Keywords: Vulvovaginal, Candida, Characterization, Phylogeny, Molecular.
[Full Text Article]