Candidiasis : the emergence of a novel species, Candida dubliniensis

The incidence of fungal infections in people has increased dramatically over the past 2 decades, as has the number and variety of infecting fungal agents. These trends parallel a dramatic increase in the number of individuals with deficient cell-mediated immunity, particularly those infected with HIV and those receiving chemotherapeutic treatments which induce severe immunosuppression. These individuals include those having bone marrow and organ transplants and people receiving anti-cancer therapy. Furthermore, the use of broad-spectrum antibiotics, mucosal colonization by commensal yeasts, medical therapies which involve invasive surgical procedures and the use of indwelling central venous catheters render patients vulnerable to infection by a wide variety of opportunistic fungal pathogens, particularly Candida species. Because of the growing number of immunocompromised patients it is perhaps inevitable that novel fungal species capable of causing opportunistic infections will be recognized. Many new fungal species are described each year and many of these have been reported to cause disease in humans. The objectives of this review are to briefly summarize the clinical manifestations and epidemiology of oral candidiasis in HIV-infected and AIDS patients and to describe the discovery and characterization of Candida dubliniensis, a novel species of yeast associated with oral candidiasis in this patient group, in diverse geographical locations.