Abstract:
Purpose: The use of contraceptive devices predisposes women
to vulvovaginal candidiasis globally. Despite the high incidence of
vulvovaginal candidiasis and antifungal resistance to azoles, the ge-
netic diversity and resistance pattern among contraceptive users in
Nigeria is poorly investigated. This study therefore sought to char-
acterize and determine the phylogenetic breadth of Candida spp.
as well as their resistance to antifungal agents from women using
contraceptive devices in central Nigeria.
Methods & Materials: This study recruited 1,600 women using
contraceptive devices that visited gynaecology and obstetrics clin-
ics in central Nigeria between August, 2018 to February, 2020. Can-
dida spp. were isolated and characterized using conventional meth-
ods and the sequencing of the internal transcribed spacer (ITS) re-
gion of the ribosomal DNA (rDNA). Bayesian phylogenetic analysis
was used to characterize the diversity of Candida spp. Agar well
diffusion technique and primer-specific PCR were used for the de-
termination of antifungal susceptibility profiles and the presence
of resistant genes.
Results: Five Candida spp. were identified from 710 contracep-
tive users with vulvovaginal candidiasis. Although Candida albi-
cans was the predominant (43.23%) Candida spp. isolated, other
non-albicans Candida spp. included C. glabrata (19.01%) C. tropi-calis (15.77%) C. parapsilosis (8.87%) and C. akabanensis (13.09%) re-
spectively. The molecular characterization of the different Candida
spp. and their phylogenetic relationships were confirmed using the
Bayesian analysis. All the Candida spp. revealed varying degrees
of susceptibilities to voriconazole, fluconazole and nystatin. How-
ever, C. albicans showed 29.0% resistance to fluconazole, C. tropi-
calis showed 46.0% and 14.0% resistance to nystatin and voricona-
zole while C. akabanensis showed 100% resistance to voriconazole
and fluconazole, respectively. Kruskal-Wallis Chi-square test using
‘R’ (Version 3.2.2) showed nystatin as the most effective antifungal
agent (Kruskal-Wallis χ2 = 786.03, df = 2, P < 0.001) against Can-
dida spp. Also, resistant gene Erg11 was identified in all the Candida
spp. resistant to the antifungal agents tested.
Conclusion: Women using contraceptive devices in central
Nigeria harbour phylogenetically diverse Candida spp. including C.
akabanensis an uncommon cause of vulvovaginal candidiasis. Out
of these Candida spp. C. albicans, C. tropicalis and C. akabanensis
are notable for multidrug drug resistance as well as harbouring re-
sistant gene Erg11.
