Objective: To analyze experimental and clinical data on diabetes mellitus (DM) related to infections with focus on vaginal mycosis. To evaluate a role of DM in the epidemiology of vulvovaginal candidiasis.
Design: Review.
Setting: Department of Clinical Microbiology, Department of Biological and Medical Sciences, Faculty of Pharmacy, Department of Obstetrics and Gynecology, Charles University in Prague, Faculty of Medicine and University Hospital Hradec Kralove.
Methods: Review of literature data.
Results: DM is a risk factor for fungal infections caused by yeasts (Candida albicans), members of Mucorales fungi, some dimorphic fungi (Coccidioides) and agents of onychomycosis. DM is usually associated only with increased colonization of the anatomical sites (oral cavity, vagina), and/ or with an intensified symptomatology of infection (onychomycosis, mucormycosis). Diabetic patients with oropharyngeal and vulvovaginal candidiasis have frequently changed etiology spectrum. The patients with VVC and DM, especially of older age or with prone to relapses, have tendency to shift of the spectrum to non-albicans species, mainly C. glabrata. Treatment of VVC in diabetic patients can be complicated owing to unfavourable antifungal susceptibility profile (C. glabrata) and/ or adverse interactions between some azole antifungals and sulfonylurea-based antidiabetics.
Conclusion: Diabetes mellitus is often cited as a risk factor, although in many cases there is a lack of reliable and clinically relevant information. This does not mean that this disease can be underestimated. On the contrary, it is necessary to get the DM as soon as possible under control and thus prevent complications when infection develops. Individual approach should be applied to the diabetic patients at risk of an infection. Yeast colonization and development of vaginal infection is complex process primarily dependent on sexual hormones, indigenous microbiota and finely tuned mechanisms of local immunity. Role of DM consists in the fact that it is one of the important co-factors that can change the setup of the vaginal environment in favour of yeasts and thus promote or facilitate the development of VVC.