Distinct gut microbiota profiles in patients with primary sclerosing cholangitis and ulcerative colitis

AIM To characterize the gut bacterial microbiota of patients with primary sclerosing cholangitis(PSC) and ulcerative colitis(UC).METHODS Stool samples were collected and relevant clinical data obtained from 106 study participants, 43 PSC patients with(n = 32) or without(n = 11) concomitant inflammatory bowel disease, 32 UC patients, and 31 healthy controls. The V3 and V4 regions of the 16 S ribosomal RNA gene were sequenced on Illumina Mi Seq platform to cover low taxonomic levels. Data were further processed in QIIME employing Ma As Lin and LEf Se tools for analysis of the output data.RESULTS Microbial profiles in both PSC and UC were characterized by low bacterial diversity and significant change in global microbial composition. Rothia, Enterococcus, Streptococcus, Veillonella, and three other genera were markedly overrepresented in PSC regardless of concomitant inflammatory bowel disease(IBD). Rothia, Veillonella and Streptococcus were tracked to the species level to identify Rothia mucilaginosa, Streptococcus infantus, S. alactolyticus, and S. equi along with Veillonella parvula and V. dispar. PSC was further characterized by decreased abundance of Adlercreutzia equolifaciens and Prevotella copri. Decrease in genus Phascolarctobacterium was linked to presence of colonic inflammation regardless of IBD phenotype. Akkermansia muciniphila, Butyricicoccus pullicaecorum and Clostridium colinum were decreased in UC along with genus Roseburia. Low levels of serum albumin were significantly correlated with enrichment of order Actinomycetales.CONCLUSION PSC is associated with specific gut microbes independently of concomitant IBD and several bacterial taxa clearly distinguish IBD phenotypes(PSC-IBD and UC).

Risk of recurrence of primary sclerosing cholangitis after liver transplantation is associated with de novo inflammatory bowel disease

AIM To evaluate risk factors for primary sclerosing cholangitis(PSC) recurrence(rPSC) after orthotopic liver transplantation(OLT) in patients with well-preserved colons. METHODS We retrospectively evaluated the medical records of all patients transplanted for PSC in our center between July 1994 and May 2015 and selected 47 with followup of at least 60 mo for further analysis based on strict inclusion and exclusion criteria. rPSC was confirmed by magnetic resonance or endoscopic retrograde cholangiopancreatography and liver biopsy. All patients were evaluated by protocolary pre-OLT colonoscopy with randomized mucosal biopsies. Colonoscopy was repeated annually after OLT. Both organ donors and recipients were human leukocyte antigen(HLA) typed by serological and/or DNA methods. All input data were thoroughly analyzed employing relevant statistical methods.RESULTS Altogether, 31 men and 16 women with a median(range) age of 36(15-68) years at the time of OLT and a median follow-up of 122(60-249) mo were included. rPSC was confirmed in 21/47(44.7%) of patients, a median 63(12-180) mo after transplantation. De novo colitis [rPSC in 11/12, P ≤ 0.05, hazard ratio(HR): 4.02, 95% confidence interval(CI): 1.58-10.98] and history of acute cellular rejection(rPSC in 14/25, P ≤ 0.05; HR: 2.66, 95%CI: 1.03-7.86) showed strong positive associations with rPSC. According to the univariate analysis, overlapping features of autoimmune hepatitis(r PSC in 5/5, P ≤ 0.05) and HLA-DRB1*07 in the donor(r PSC in 10/15, P ≤ 0.05) represent other potential risk factors for rPSC, while the HLA-DRB1*04(rPSC in 0/6, P ≤ 0.05), HLA-DQB1*03(rPSC in 1/11, P ≤ 0.05), and HLA-DQB1*07(rPSC in 0/7, P ≤ 0.05) recipient alleles may have protective roles.CONCLUSION De novo colitis and acute cellular rejection are clinical conditions significantly predisposed towards recurrence of PSC after liver transplantation.