Oral Candida infection and colonization in solid organ transplant recipients

Abstract

Introduction Oral Candida carriage and infection have been reported to be associated with a greater risk for systemic infection in transplant recipients; however, a systematic analysis of the oral Candida titers and species has not been previously conducted. The objectives of this study were to determine the prevalence of oropharyngeal candidiasis, the oral carrier status, Candida titers and species in this population. Methods Ninety kidney and heart transplant subjects and 72 age-matched healthy controls were included. Swabs from the oral mucosa and a standardized amount of unstimulated saliva were plated on Chromagar™ Candida, and colony-forming units per millilitre were calculated. Initial speciation was based on colony color and was confirmed by standard germ tube, biotyping, or polymerase chain reaction assays. Results Infection with C. albicans was detected in seven transplant subjects and none of the controls. The transplant group had significantly higher oral Candida titers than the control group. There were no statistically significant relationships between the dose or type of immunosuppressants and oral Candida titers or infection. A significantly higher percentage of transplant subjects were colonized by more than one species, compared with control subjects. The most frequent species combination in transplant subjects was C. albicans and C. glabrata. C. glabrata was isolated from 13.5% of transplant carriers and none of the controls. Conclusions Increased oral Candida infection and carriage titers were found in the transplant population. Although the majority of transplant patients were colonized by C. albicans, C. glabrata appears to emerge as the second most prevalent species.

Shaping the oral mycobiota: interactions of opportunistic fungi with oral bacteria and the host

“…A global analysis using 454 pyrosequencing showed a significant shift in the oral mycobiome, with Epicoccum and Alternaria abundantly colonizing HIV-infected patients but not healthy individuals, whereas Candida was abundant in both groups [16]. In pharmacologically immunosuppressed solid organ transplant recipients both culture and pyrosequencing studies showed the oral mycobiota to be dominated by Candida species [23–25]. Candida species load and diversity were positively correlated with the dose of mycophenolate mofetil in a renal transplant population, suggesting a causal link [24].…”

Molecular Fingerprints to IdentifyCandidaSpecies

“…C. glabrata has been reported to be the second etiologic agent, after C. albicans , of superficial and invasive candidiasis in adults in the United States [18, 19], whereas, in Europe and Latin America, C. parapsilosis is the specie responsible for approximately 45% of all cases of candidemia [14, 20]. …”

Oral candidiasis in patients with renal transplants

“…Candida species can trigger infections of the bloodstream and esophagus as well as other organs in RTPs (6,7). Oral candidiasis (OC) can predispose such patients to esophageal candidiasis, an invasive form of infection with significant morbidity (5,8). …”

“…Previous studies have shown that RTPs have considerably higher prevalence of OC than healthy controls (HCs), and this condition is the most frequent oral infection in RTPs, with a prevalence ranging between 7.7% and 46.7% (8-13). …”

“…However, studies of the potential risk factors and predictors for this condition in RTPs are lacking. In addition, some studies suggested that oral infections, including candidiasis, are more severe in the immediate posttransplantation period (4,5), but cross-sectional studies of OC in RTPs did not support this finding (8-13). In this sense, a longitudinal design would be more reliable to analyze whether OC is more common in the immediate posttransplantation period and study its associated factors.…”