Alterations of the salivary and fecal microbiome in patients with primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a chronic, progressive liver disease known for its frequent concurrence with inflammatory bowel disease. PSC can progress to cirrhosis, end-stage liver disease, hepatobiliary cancer, and/or colorectal cancer. The etiopathogenesis of PSC remains poorly understood, and, as such, pharmacotherapy has yet to be definitively established. Little is known about the salivary microbiome in PSC and PSC-IBD. This study aimed to evaluate the oral microbiome of patients with PSC, with association to these patient's fecal microbial composition. METHODS: Saliva, fecal samples and Food Frequency Questionnaires were collected from 35 PSC patients with or without concomitant inflammatory bowel disease and 30 age- and BMI-matched healthy volunteers. 16S rRNA gene sequencing was performed using Illumina MiSeq platform. RESULTS: The salivary microbial signature of PSC was significantly altered as compared to healthy controls, independent of concomitant IBD, and was comprised of 19 significantly altered species, of which, eight species were consistently overrepresented in both fecal and saliva of patients with PSC, including Veillonella, Scardovia and Streptococcus. CONCLUSIONS: PSC is characterized by microbial dysbiosis in the gut and the salivary microbiome, independently from IBD. The PSC dysbiotic signature includes a reduction in autochthonous bacteria and an increased relative abundance of pathogenic bacteria, including an invasion of oral bacteria to the gut. PSC is a strong modulator of the microbial profile, in the gut and the oral microbiome. These results may lead to the development of biomarkers for screening and early diagnosis or the development of personalized medicine in PSC.

Low weight predicts neutropenia and peginterferon alfa-2a dose reductions during treatment for chronic hepatitis C.

Treatment-induced neutropenia frequently complicates the treatment course of patients treated with pegylated interferon alfa and ribavirin for chronic hepatitis C. We investigated the effect of weight on the risk for dose reductions caused by neutropenia in patients treated with a weight-independent dose of peginterferon alfa-2a. We retrospectively analysed single centre data for 172 patients enrolled in a multi-centre, open-label trial of peginterferon alfa-2a and ribavirin for chronic hepatitis C. Low body weight was significantly associated with dose reductions due to neutropenia. Patients weighing less than 62 kg had a 35% risk for significant neutropenia as opposed to a 12% risk for heavier patients (P = 0.001), and this side-effect occurred earlier during treatment. Low weight was an independent risk factor by multivariate analysis (hazard ratio 0.956/kg). The risk for treatment-induced neutropenia was associated with body surface area more than with the body mass index. In conclusion, a low pre-treatment weight strongly predicts the need for peginterferon alfa-2a dose reductions. This apparently reflects overall body size more than body fat content. It is prudent to frequently monitor blood counts for smaller-sized patients, especially during the first weeks of treatment.