Use of 18S ribosomal DNA polymerase chain reaction-denaturing gradient gel electrophoresis to study composition of fungal community in 2 patients with intestinal transplants.

Fungi form a diverse microbial community in the human intestine. Little is known about the succession of species after intestinal transplantation. We investigated the alterations of the gut fungal population in 2 patients with intestinal allografts. The ileal effluent and feces were fingerprinted using denaturing gradient gel electrophoresis, with confirmation by DNA sequencing. Analysis of 18S ribosomal DNA indicated that the phylogenetic diversity of the fungal communities was higher soon after transplantation; less diversity was observed at the later time points in patient 1. The shifts in the denaturing gradient gel electrophoresis banding patterns over time were similar in the effluent and feces in this patient. Similar changes in the fungi in the effluent and feces also were observed in patient 2. Sequence analysis of denaturing gradient gel electrophoresis bands showed that Saccharomyces cerevisiae and Kluyveromyces waltii dominated the fungal microbiota in both patients. Some species, including Candida spp, Cryptococcus neoformans, Fusarium oxysporum, Aspergillus clavatus, and Trichophyton verrucosum, were present early. We report for the first time the temporal alterations in fungal communities in patients with an intestinal allograft. This information may provide novel insight into the roles of the fungal microbiota in the pathophysiology of the transplanted intestine.