Candida tropicalis: its prevalence, pathogenicity and increasing resistance to fluconazole

Candida tropicalis has been identified as the most prevalent pathogenic yeast species of the Candida-non-albicans group. Historically, Candida albicans has been the major species responsible for causing candidiasis in immunocompromised and immunocompetent patients. However, infections (candidiasis) due to C. tropicalis have increased dramatically on a global scale thus proclaiming this organism to be an emerging pathogenic yeast. The reasons for this organism's dominance and its resistance to fluconazole have been difficult to elucidate. In addition, the mechanism of this organism's pathogenicity and the consequent immune response remain to be clarified. This paper describes certain predisposing factors potentially responsible for these characteristics and presents a 'root cause analysis' to explain the increasing prevalence of C. tropicalis in developed and undeveloped countries, as well as the organism's acquired drug resistance. Control measures against fluconazole resistance in clinical management have also been discussed.