Candida Infections in Hematopoietic and Solid Organ Transplant Recipients

Abstract

Infections caused by Candida species range from local mucous membrane involvement to widely disseminated disease. In patients who have received a hematopoietic cell or solid organ transplant, candidiasis is one of the most common infections that is seen and is often life threatening. Candida species are part of the normal human microbiota and, as such, rarely cause infection in healthy hosts. Infections arise when the organisms are able to proliferate locally and gain access to the bloodstream from their normal mucosal or cutaneous colonization niche. Candidemia and invasive candidiasis are directly attributable to a breakdown of normal barriers, such as that which occurs with candidemia related to a central venous catheter, or to impairment of host defenses, which is especially prominent with neutropenia. The most common species to cause infection is Candida albicans, but increasingly, Candida glabrata is reported, especially among patients who have hematological malignancies or have received a transplant. Treatment has improved in the last several decades with the availability of multiple azole and echinocandin agents, all of which are less toxic than amphotericin B. However, crude mortality rates for patients with candidemia remain high, reflecting in part the very ill patients who develop this infection. Increasing evidence shows that the sooner antifungal treatment is initiated, the better the outcome; thus, in patients at high risk for invasive candidiasis, empirical treatment is appropriate while awaiting diagnostic test results. Prophylaxis, generally with an azole agent, is given routinely to recipients of a hematopoietic cell transplant and to certain high-risk solid organ transplant recipients.