title: Gut microbial community structure and complications after kidney transplantation: a pilot study.
abstract: BACKGROUND
  The gut microbiome plays a role in the regulation of the immune system.
  
  
  METHODS
  We prospectively enrolled 26 kidney transplant recipients and collected serial fecal specimens (N=85) during the first three months of transplantation. We characterized bacterial composition by polymerase chain reaction amplification of the 16S rRNA V4-V5 variable region and deep sequencing using the Illumina MiSeq platform.
  
  
  RESULTS
  An increase in the relative abundance of Proteobacteria was observed in the posttransplantation specimens compared to pretransplantation specimens (P=0.04, Wilcoxon signed-rank test). In patients with posttransplant diarrhea, the mean(±standard deviation [SD]) Shannon diversity index was lower in those with diarrhea (N=6) than those without diarrhea (N=9) (2.5±0.3 vs. 3.4±0.8; P = 0.02, Wilcoxon rank-sum test). Principal coordinate analysis showed clear separation between the two groups, and linear discriminant analysis effect size (LEfSe) method revealed that Bacteroides, Ruminococcus, Coprococcus, and Dorea were significantly lower in the patients with diarrhea. Principal coordinate analysis also showed clear separation between the acute rejection (AR) group (N=3) and the no AR group (N=23) and the LEfSe method revealed significant differences between the two groups. Fecal abundance of Enterococcus was associated with Enterococcus urinary tract infection (UTI). The median Enterococcus fecal abundance was 24% (range, 8%-95%) in the three patients with Enterococcus UTI compared to 0% in the 23 patients without Enterococcus UTI (interquartile range, 0.00%-0.08%) (P=0.005, Wilcoxon rank-sum test).
  
  
  CONCLUSIONS
  Our pilot study identified significant alterations in the gut microbiota after kidney transplantation. Moreover, distinct microbiota structures were observed in allograft recipients with posttransplant diarrhea, AR, and Enterococcus UTI.
authors.affiliation: 1 Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medical College, New York, NY. 2 Department of Transplantation Medicine, New York Presbyterian Hospital-Weill Cornell Medical Center, New York, NY. 3 Infectious Diseases Services, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY. 4 Current address: New York Genome Center, New York, NY. 5 Address correspondence to: John Lee, M.D., Department of Medicine, Division of Nephrology and Hypertension 525 East 68th Street, Box 3, New York, NY 10065.
authors.forename: John R
authors.initials: JR
authors.lastname: Lee
authors.forename: Thangamani
authors.initials: T
authors.lastname: Muthukumar
authors.forename: Darshana
authors.initials: D
authors.lastname: Dadhania
authors.forename: Nora C
authors.initials: NC
authors.lastname: Toussaint
authors.forename: Lilan
authors.initials: L
authors.lastname: Ling
authors.forename: Eric
authors.initials: E
authors.lastname: Pamer
authors.forename: Manikkam
authors.initials: M
authors.lastname: Suthanthiran
mesh_terms: D000328:Adult; D000368:Aged; D003967:Diarrhea; D016983:Enterococcus / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D005260:Female; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D007676:Kidney Failure, Chronic / Q000150:complications / Q000601:surgery*; D016030:Kidney Transplantation / Q000009:adverse effects*; D016014:Linear Models; D008297:Male; D064307:Microbiota; D008875:Middle Aged; D010865:Pilot Projects; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D020560:Proteobacteria / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D012336:RNA, Ribosomal, 16S