Diagnostic laboratory techniques in vaginal candidosis

The laboratory diagnosis of vulvovaginal candidosis is complicated by the fact that the Candida spp., mainly C. albicans, are found as commensals in the normal vagina. Therefore, the demonstration of Candida in material from the vagina by microscopy (KOH mounts or Gram smears) and/or culture on Sabouraud's agar does not necessarily confirm infection. For this reason, attention is frequently paid to the quantity of yeast isolated in culture and to the morphological form of the organism (yeast/mycelium) seen in the clinical material. However, there is controversy as to whether either of these two criteria, which may be influenced by sampling methods, sample type, sample age, etc, are reliable indicators of Candida infection and correlate with the signs and symptoms attributed to this condition. A more accurate measure of the quantity of Candida present in the vagina may be obtained by measurement of yeast antigen levels in material such as vaginal washings. Correlation of antigen levels with signs and symptoms of infection is required, as is an appraisal of the role of these antigens in the pathogenesis of vulvovaginal candidosis. A new and more rapid method for diagnosis of vulvovaginal candidosis, based on the detection of Candida antigens with a slide latex agglutination test, has been recently introduced.