Inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn's disease (CD), are chronic debilitating disorders of unknown etiology. Over 200 genetic risk loci are associated with IBD, highlighting a key role for immunological and epithelial barrier functions. Environmental factors account for the growing incidence of IBD, and microbiota are considered as an important contributor. Microbiota dysbiosis can lead to a loss of tolerogenic immune effects and initiate or exacerbate inflammation. We aimed to study colonic mucosal microbiota and the expression of selected host genes in pediatric UC. We used high-throughput 16S rDNA sequencing to profile microbiota in colonic biopsies of pediatric UC patients (n = 26) and non-IBD controls (n = 27). The expression of 13 genes, including five for antimicrobial peptides, in parallel biopsies was assessed with qRT-PCR. The composition of microbiota between UC and non-IBD differed significantly (PCoA, p = 0.001). UC children had a decrease in Bacteroidetes and an increase in several family-level taxa including Peptostreptococcaceae and Enterobacteriaceae, which correlated negatively with the expression of antimicrobial peptides REG3G and DEFB1, respectively. Enterobacteriaceae correlated positively with the expression siderophore binding protein LCN2 and Betaproteobacteria negatively with DEFB4A expression. The results indicate that reciprocal interaction of epithelial microbiota and defense mechanisms play a role in UC.
Clostridium difficile colitis (CDC) is associated with an increased short-term mortality risk in hospitalised ulcerative colitis (UC) patients. We sought to determine whether CDC also impacts long-term risks of adverse health events in this population.
To determine whether CDC also impacts long-term risks of adverse health events in this population.
A population-based retrospective cohort study was conducted of UC patients hospitalised in Ontario, Canada between 2002 and 2008. Patients with and without CDC were compared on the rates of adverse health events. The primary outcomes were the 5-year adjusted risks of colectomy and death.
Among 181 patients with CDC and 1835 patients without CDC, the 5-year cumulative colectomy rates were 44% and 33% (P = 0.0052) and the 5-year cumulative mortality rates were 27% and 14% (P
The presence of Mycobacterium avium subspecies paratuberculosis (MAP) has previously been inferred in the genesis of Crohn's disease (CD), and a higher incidence of MAP PCR positivity has been demonstrated in the gut and peripheral blood of CD patients than in healthy individuals. The objective of this prospective study was to assess the potential etiological role of MAP in the pathogenesis of CD.
The presence of mycobacteria was assessed in bowel biopsies from newly diagnosed, treatment naïve Norwegian patients with IBD, including CD and ulcerative colitis (UC), as compared to a hospital-based cohort of CD and UC patients. Biopsies were collected from the small and large bowel in 354 individuals with suspected IBD. Detection of mycobacteria was performed by long-term cultivation in combination with direct detection by MAP IS900-specific PCR.
Among the specimens included from the patients with early IBD, samples from only two of the patients with CD (2.7%) and two of the non-IBD controls (1.5%) exhibited a positive growth signal. None of the CD patients and only one of the non-IBD controls was MAP PCR positive. Only the single PCR positive non-IBD control was also mycobacterial culture positive with Mycobacterium avium subsp. hominissuis. In the referral patients with long-term IBD, the prevalence of growth signal and MAP PCR positivity was higher (52 and 9%, respectively).
These findings demonstrate the paucity of MAP in the gut of treatment naïve CD patients. This study does not provide evidence for a role of MAP in early IBD.
The colectomy rate in patients with ulcerative colitis has increased during the last 30 years in Stockholm County due to increased incidence and a more liberal attitude to colectomy in acute cases. In an area of Stockholm's size, about 30 patients with UC will require colectomy every year and of these, 12 will be acute cases. The main factor affecting the colectomy rate was the extent of disease at diagnosis. The 25-year cumulative colectomy rate was 65% in patients with total colitis compared to 45% in all patients. The probability of undergoing a colectomy decreased as the duration of disease increased and after five years duration of disease the colectomy rate was about 1% per year. The choice of primary surgical procedure has changed during the study period and subtotal colectomy and ileostomy is now preferred as the surgical procedure of choice, both in acute and elective cases. The frequency of major complications was constant during the period of study but increased with the urgency of intervention, being 25% in elective cases and 46% in acute cases. The overall postoperative mortality fell from 13% during 1960 to 1964 to 2% during 1980-1984. In acute cases the mortality during the same time periods decreased from 36% to 3%. The long-term results of ileorectal anastomosis showed a substantial failure rate and the most common cause of failure was recurrent rectal disease. In patients who still had their ileorectal anastomosis at the time of follow-up the functional results were better than for the pelvic pouch. The ileorectal anastomosis is for some patients a definite solution and in others it avoids or delays an ileostomy and at the same time still permits a pelvic pouch at a later date. The need for secondary surgery after colectomy for UC is great. The cumulative probability of a fist small intestinal obstruction requiring surgery in 483 patients treated by colectomy was 23% after 15 years. The annual incidence was highest in patients treated by pelvic pouch and lowest in patients treated by IRA. The cumulative probability of a first ileostomy revision was 21% after 15 years. In patients with a Kock's pouch the cumulative probability of a first nipple revision was as high as 52% after two years. The need for secondary surgery was initially high in patients treated by pelvic pouch but the need has decreased during the latter years due to improved technique and increasing surgical experience.(ABSTRACT TRUNCATED AT 400 WORDS)