Increased cytokine transcripts in pouchitis reflect the degree of inflammation but not the underlying entity

Pouchitis: what every gastroenterologist needs to know

Pouchitis is the most common complication among patients with ulcerative colitis who have undergone restorative proctocolectomy with ileal pouch-anal anastomosis. Pouchitis is actually a spectrum of diseases that vary in etiology, pathogenesis, phenotype, and clinical course. Although initial acute episodes typically respond to antibiotic therapy, patients can become dependent on antibiotics or develop refractory disease. Many factors contribute to the course of refractory pouchitis, such as the use of nonsteroidal anti-inflammatory drugs, infection with Clostridium difficile, pouch ischemia, or concurrent immune-mediated disorders. Identification of these secondary factors can help direct therapy.

Acute and chronic pouchitis--pathogenesis, diagnosis and treatment

Restorative proctocolectomy with ileal pouch-anal anastomosis has become the procedure of choice for the majority of patients with ulcerative colitis who require surgical treatment. Pouchitis, the most common long-term complication of the procedure, involves a spectrum of disease processes with heterogeneous risk factors, clinical features, disease courses and prognoses. In addition, clinical symptoms of pouchitis are not specific and often overlap with those of other inflammatory and functional pouch disorders, such as Crohn's disease of the pouch and irritable pouch syndrome. Pouchoscopy and biopsy, along with laboratory and radiographic evaluations, are often required for accurate diagnosis in patients with symptoms indicative of pouchitis. Dysbiosis has been implicated as a triggering factor for pouchitis, and concurrent infection with pathogens, such as Clostridium difficile, might contribute to disease relapse and exacerbation. Antibiotic therapy is the main treatment modality. However, the management of antibiotic-dependent and antibiotic-refractory pouchitis remains challenging. Secondary causes of pouchitis, such as ischaemia, NSAID use, the presence of concurrent primary sclerosing cholangitis and other systemic immune-mediated disorders, should be evaluated and properly managed.

Depression and mucosal proinflammatory cytokines are associated in patients with ulcerative colitis and pouchitis - A pilot study

BACKGROUND AND AIMS

Recent studies demonstrated that depression was associated with mucosal inflammation in patients with ulcerative colitis (UC). This association had not been studied in patients with UC with ileal pouch-anal anastomosis (IPAA) after restorative proctocolectomy. We hypothesized that depression and mucosal proinflammatory cytokines in UC-patients with pouchitis were associated.

METHODS

We assessed 18 IPAA-UC-patients with pouchitis and 19 IPAA-UC-patients without pouchitis. Mucosal biopsies were taken from the areas with maximal inflammation in the pouch or from the posterior wall of the pouch if the pouch had a normal endoscopic appearance. Disease activity was assessed by the Pouch Disease Activity Index. The expression of mucosal proinflammatory gene transcripts (interleukin-8 [IL-8] and interleukin-1ß [IL-1b]) was quantified by real-time polymerase chain reaction. Depression was assessed by the Hospital Anxiety and Depression Scale (HADS). Pearson correlations between depression and cytokine transcripts were calculated.

RESULTS

The correlation of HADS depression scores of patients with pouchitis with IL-8 was r=0.51 (p=0.03) and with IL-1ß was r=0.47 (p=0.04). The correlation between the HADS depression scores of patients without pouchitis with IL-8 was r=-0.19; (p=0.21) and with IL-1ß was r=-0.12 (p=0.30).

CONCLUSION

Depression is associated with mucosal proinflammatory cytokines in patients with pouchitis after restorative proctocolectomy in patients with UC.

Perioperative factors during ileal pouch-anal anastomosis predict pouchitis

PURPOSE

Pouchitis is the most common complication of IPAA. Identifying factors predictive of pouchitis may improve outcomes by modifying contributing factors and enhancing patient selection. The most objective means for confirming pouchitis is by histology because the clinical and endoscopic diagnoses rely on more subjective assessments. The importance of histological pouchitis in the absence of clinical or endoscopic findings is unknown.

METHODS

Prospectively collected data on patients with IPAA and pouch surveillance were evaluated. Patients who developed pouchitis, defined as symptoms of pouchitis confirmed by endoscopic biopsy (group B) were compared with those without any episode of clinical, endoscopic, or histological pouchitis (group A) for pre- and intraoperative factors and outcomes. Asymptomatic patients with histological pouchitis on surveillance biopsies (group C) were further compared with group A. Patients with Crohn's disease were excluded.

RESULT

Of the 673 patients with pouch biopsies, 422 (62.7%) were in group A, 161 (23.9%) in group B, and 90 (13.4%) in group C. Mean follow-up was 9.8 (±5.1), 12.4 (±5.4), and 13. (±4.7) years. Of the 43 preoperative factors evaluated, those associated with group B included leukocytosis (P < .001), rheumatologic extraintestinal disease (P < .001), disease proximal to splenic flexure (P = .001), pulmonary comorbidity (P = .004), prior steroid use (P = .006), and age at operation and diagnosis (P = .018 and .021). Of the 10 intraoperative factors evaluated, pouchitis was associated with S-pouch reconstruction (P < .001), transfusion (P < .001), and 2-stage instead of 3-stage operation (P = .05), all surrogates for operative complexity. On multivariate analysis, pulmonary comorbidity (OR 3.38, 95% CI 1.62-7.07), disease proximal to splenic flexure (OR 2.37, 95% CI 1.18-4.77), extraintestinal disease manifestations (OR 1.6, 95% CI 1.01-2.54), and S-pouch reconstruction (OR 1.59, 95% CI 0.99 - 2.54) were associated with pouchitis. Patients in group B had worse outcomes, including more strictures (P = .015), bowel obstructions (P = .019), fistulas (P = .18), and lower quality of life (P < .001). Group C patients had the same outcomes as those in group A and the finding was not predicted by the above-mentioned parameters.

CONCLUSION

Patients with symptomatic, biopsy-confirmed pouchitis have worse long-term outcomes than those without pouchitis. This complication is associated with specific pre- and intraoperative factors. Histological pouchitis incidentally found on surveillance biopsy in asymptomatic patients is of no clinical relevance and does not influence outcome. Identification of these preoperative factors associated with the subsequent development of pouchitis will strengthen patient counseling and may facilitate risk stratification.

Activation of signal transducer and activator of transcription-1 (STAT-1) and differential expression of interferon-gamma and anti-inflammatory proteins in pelvic ileal pouches for ulcerative colitis and familial adenomatous polyposis

Pouchitis after total rectocolectomy is the most common complication of ulcerative colitis (UC). The immunological mechanisms involved in the genesis of pouchitis are unclear. Therefore, we evaluated the inflammatory activity in normal ileal pouch mucosa by determining signal transducers and activators of transcription (STAT-1) activation and cytokine expression in patients operated for UC and familial adenomatous polyposis (FAP). Eighteen asymptomatic patients, who underwent total rectocolectomy and J pouch, were evaluated: nine with UC and nine with FAP. The activation of STAT-1 and cytokine expression were determined by immunoblot of total protein extracts from pouch mucosal biopsies. The absence of pouchitis was assessed by clinical, histological and endoscopic parameters, according to the Pouchitis Disease Activity Index. The patients were not receiving any medication. Analysis of variance (anova) and Tukey-Kramer's test were applied. The local ethical committee approved the study and informed consent was signed by all participants. STAT-1 activation was increased in UC when compared to FAP and controls (P < 0.05). Higher levels of interferon (IFN)-gamma expression were observed in UC patients when compared to the control group (P < 0.05), but were similar to FAP. In contrast, cytokine signalling (SOCS-3) and interleukin (IL)-10 expression were similar in all groups (P > 0.05). These findings could explain the higher susceptibility to this inflammatory complication in UC when compared to FAP. A tendency towards increased levels of IFN-gamma and STAT-1 in patients with UC, even without clinical and endoscopic evidence of pouchitis, was observed; studying inflammatory activity in asymptomatic ileal pouches may help understanding of the pathogenesis of pouchitis.

Asymmetric endoscopic inflammation of the ileal pouch: a sign of ischemic pouchitis?

BACKGROUND

Pouchitis is associated with dysbiosis and dysregulated mucosal immunity, although secondary pouchitis with special etiologic factors, such as ischemia, can occur. The aim was to describe a disease phenotype of the ileal pouch with an endoscopic appearance suggestive of ischemia.

METHODS

We identified consecutive patients with endoscopic asymmetric inflammation of the pouch (inflammation of side of the pouch with a completely normal other limb of the pouch one limb and a sharp demarcation along the staple suture line). Patients with Crohn's disease (CD) of the pouch or antibiotic-responsive pouchitis, matched for duration of the pouch, served as controls. Histology slides of mucosal biopsies were re-reviewed independently by 2 blinded gastrointestinal pathologists. Demographic, clinical, endoscopic, histologic, and imaging characteristics were compared between the groups.

RESULTS

Ten patients with "ischemic" pouchitis, 15 with CD of the pouch, and 15 with antibiotic-responsive pouchitis were studied. Pyloric gland metaplasia was observed only in the groups with CD of the pouch (23.1%) or antibiotic-responsive pouchitis (13.3%). Of patients with "ischemic" pouchitis, 80% had extracellular hemosiderin or hematoidin deposits (versus 30.8% those with CD of the pouch and 13.3% of those with pouchitis, P = 0.003). The majority of patients (80%) with "ischemic" pouchitis did not respond to conventional antibiotic therapy. It appeared that subsequent abdominal surgeries after pouch construction and a history of postoperative portal vein thrombi were associated with "ischemic" pouchitis.

CONCLUSIONS

Endoscopic asymmetric inflammation of the pouch may represent an ischemia-associated pouchitis with characteristic clinical, radiographic, and histologic features. Its hemodynamic, cellular, and molecular basis of mechanism warrants further study.

Pouchitis and pouch dysfunction

Restorative proctocolectomy with ileal pouch-anal anastomosis has become the surgical treatment of choice for most patients with ulcerative colitis who require surgery. Although the surgical procedure offers a cure in some patients, postoperative inflammatory and noninflammatory complications are common. Pouchitis is the most common long-term complication of the procedure. Pouchitis represents a spectrum of disease processes with heterogeneous risk factors, clinical phenotypes, natural history, and prognosis. Accurate diagnosis and classification are important for proper treatment and prognosis.

Impaired immune functions of monocytes and macrophages in Whipple's disease

BACKGROUND & AIMS

Whipple's disease is a chronic multisystemic infection caused by Tropheryma whipplei. Host factors likely predispose for the establishment of an infection, and macrophages seem to be involved in the pathogenesis of Whipple's disease. However, macrophage activation in Whipple's disease has not been studied systematically so far.

METHODS

Samples from 145 Whipple's disease patients and 166 control subjects were investigated. We characterized duodenal macrophages and lymphocytes immunohistochemically and peripheral monocytes by flow cytometry and quantified mucosal and systemic cytokines and chemokines indicative for macrophage activation. In addition, we determined duodenal nitrite production and oxidative burst induced by T whipplei and by other bacteria.

RESULTS

Reduced numbers of duodenal lymphocytes, increased numbers of CD163(+) and stabilin-1(+), reduced numbers of inducible nitric synthase+ duodenal macrophages, and increased percentages of CD163(+) peripheral monocytes indicated a lack of inflammation and a M2/alternatively activated macrophage phenotype in Whipple's disease. Incubation with T whipplei in vitro enhanced the expression of CD163 on monocytes from Whipple's disease patients but not from control subjects. Chemokines and cytokines associated with M2/alternative macrophage activation were elevated in the duodenum and the peripheral blood from Whipple's disease patients. Functionally, Whipple's disease patients showed a reduced duodenal nitrite production and reduced oxidative burst upon incubation with T whipplei compared with healthy subjects.

CONCLUSIONS

The lack of excessive local inflammation and alternative activation of macrophages, triggered in part by the agent T whipplei itself, may explain the hallmark of Whipple's disease: invasion of the intestinal mucosa with macrophages incompetent to degrade T whipplei.

Pouchitis and pouch dysfunction

Restorative proctocolectomy with ileal pouch-anal anastomosis has become the surgical treatment of choice for most patients with ulcerative colitis who require surgery. Although the surgical procedure offers a cure in some patients, postoperative inflammatory and noninflammatory complications are common. Pouchitis is the most common long-term complication of the procedure. Pouchitis represents a spectrum of disease processes with heterogeneous risk factors, clinical phenotypes, natural history, and prognosis. Accurate diagnosis and classification are important for proper treatment and prognosis.

Pouchitis: lessons for inflammatory bowel disease

PURPOSE OF REVIEW

One of the significant limitations to the investigation of inflammatory bowel disease (IBD) in humans is the impossibility of studying this condition from the beginning of the disease process to understand the individual contribution of the various microbiological and immunological components to its pathogenesis. Pouchitis can serve as a human model for IBD, as the time of the pouch creation is known, which allows to prospectively study the events that might eventually lead to the development of a form of intestinal inflammation (i.e., pouchitis) that mimics IBD.

RECENT FINDINGS

A considerable amount of progress has been made in the last few years on the mechanisms underlying the pathogenesis of pouchitis. Recent literature suggests that pouchitis may present a spectrum of disease processes, with a wide range of causes, risk factors, clinical phenotypes, disease courses, and prognoses. Genetic, microbiological, and immunological profiles in pouchitis were evaluated.

SUMMARY

Ileal pouch and pouchitis represent a valuable human model to study the evolution of bacterial communities and host-bacteria interactions in IBD by sequentially monitoring microbiological and immunological profile before, during, and after pouch construction and before and after development and treatment of pouchitis.

Galectin-3 expression in pouchitis in patients with ulcerative colitis who underwent ileal pouch-anal anastomosis (IPAA)

Galectin-3, an endogenous pleiotropic beta-galactoside-binding protein, which is expressed by various malignant and normal cells, regulates many biological and pathological processes, including inflammation. In the present study, we tested a possible correlation between the severity of pouchitis in patients with ulcerative colitis who underwent ileal pouch-anal anastomosis (IPAA) and the presence of galectin-3(+) macrophages in pouch mucosa. Paraffin-embedded pouch biopsies from patients with normal pouch function or chronic and recurrent acute pouchitis were immunohistostained with galectin-3, CD68, and smooth muscle actin (SMA) antibodies. Microscopic examination was performed in a blinded fashion. There was a significant decrease in the staining index of galectin-3 in the subepithelial macrophages in patients with chronic pouchitis (0.53, P=0.001; n=12) or recurrent acute pouchitis (0.43, P=0.008; n=10) when compared to patients with no clinical manifestations of pouchitis (0.63, n=12). No significant differences were noted in the lamina propria of small intestine biopsies from the same patients (from 0.63 to 0.68, P=0.24). Galectin-3 staining was restricted to CD68(+) macrophages and not present in myofibroblasts. Clinical manifestation of pouchitis is inversely correlated with galectin-3 expression in the pouches' subepithelial lamina propria macrophages.

Association between immune-associated disorders and adverse outcomes of ileal pouch-anal anastomosis

OBJECTIVES

Autoimmune disorders (ADs) frequently coexist with inflammatory bowel disease. The aim of the study was to determine whether coexisting AD in patients with ileal pouches increases the risk for chronic antibiotic-refractory pouchitis (CARP) and other inflammatory conditions of the pouch.

METHODS

A total of 622 patients seen in our Pouchitis Clinic were enrolled. We compared the prevalence of adverse outcomes of the pouch (including CARP, Crohn's disease of the pouch, and pouch failure) in patients with or without concurrent AD and assessed the factors for these adverse outcomes.

RESULTS

There were seven pouch disease categories: normal (N=60), irritable pouch syndrome (N=112), active pouchitis (N=131), CARP (N=67), Crohn's disease (N=131), cuffitis (N=83), surgical complications (N=36), and anismus (N=2). The prevalence of AD in these pouch disease categories was 4.5%, 12.5%, 9.2%, 13.4%, 10.7%, 3.8%, 1.5%, and 0%, respectively. The presence of at least one AD at time of pouch surgery was shown to be associated with a twofold increase in the risk for CARP (hazard ratio=2.29; 95% CI: 1.52, 3.46; P<0.001) and for pouch-associated hospitalization (hazard ratio=2.39; 95% CI: 1.59, 3.58; P<0.001). The presence of AD was not associated with increased risk for irritable pouch syndrome, active pouchitis, Crohn's disease, cuffitis, surgical complications, or pouch failure. Patients with Crohn's disease of the pouch had a 2.42 times higher risk for pouch failure (P=0.042) than these without. Active smoking or a history of smoking was shown to be associated with an increased risk for pouch-associated hospitalization and pouch failure.

CONCLUSIONS

AD appears to be associated with an increased risk for CARP, and the presence of the association between these AD and pouch disorders may stimulate further research on the link of these organ systems on an immunological basis.

Transcript levels of different cytokines and chemokines correlate with clinical and endoscopic activity in ulcerative colitis

Background

A definition of disease activity in ulcerative colitis (UC) is difficult. The clinical activity index (CAI) is only an indirect assessment tool of bowel inflammation and the endoscopic activity index (EAI) sometimes cannot reflect the severity of disease to the full extent. Therefore, there is a need for an objective means to quantify inflammatory activity in mucosal biopsies. In our study, we wanted to examine the correlation between transcript levels of interleukin 8 (CXCL8), interferon γ inducible protein 10 (CXCL10), myeloid-related protein 14 (calgranulin B), macrophage inflammatory protein 2 α (CXCL2) with CAI and EAI in UC.

Methods

Cytokine and chemokine transcripts were quantified using real-time PCR in 49 mucosal biopsies from 27 different patients with UC. Cytokine transcript levels were correlated with CAI and EAI.

Results

There was a statistically significant positive correlation between CXCL8 (r = 0.30; p < 0.05), CXCL10 (r = 0.40; p < 0.02), calgranulin B (r = 0.36; p < 0.03), CXCL2 (r = 0.31; p < 0.05) and CAI. Concerning EAI significant positive correlations for CXCL8 (r = 0.37; p < 0.02), CXCL10 (r = 0.33; p < 0.04), calgranulin B (r = 0.31; p < 0.05) and CXCL2 (r = 0.44; p < 0.05) were found. Low clinical and endoscopic activity was accompanied by low cytokine levels whereas high CAI and EAI were associated with high cytokine levels.

Conclusion

From our data, we conclude that real-time PCR quantification of CXCL8, CXCL10, calgranulin B and CXCL2 in colonic biopsies is a simple and objective method for grading inflammation of intestinal mucosa in UC. CXCL8, CXCL10, calgranulin B and CXCL2 might be used as biomarkers and thus as an objective tool especially in clinical trials to evaluate anti-inflammatory and immunomodulatory regimens.

Impact of orthotopic liver transplant for primary sclerosing cholangitis on chronic antibiotic refractory pouchitis

BACKGROUND & AIMS

The effect of orthotopic liver transplantation (OLT) for primary sclerosing cholangitis (PSC) and post-OLT immunosuppression on the disease course of pouchitis is not clear. The aims of this study were to compare the frequency of chronic antibiotic-refractory pouchitis (CARP) in PSC patients with or without OLT and to assess potential risk factors for CARP in these patients.

METHODS

Ulcerative colitis patients with PSC and ileal pouch-anal anastomosis (IPAA) with or without OLT identified from our prospectively maintained pouch database were analyzed. CARP was diagnosed based on persistent symptomatic pouchitis after a 4-week single- or dual-antibiotic therapy.

RESULTS

A total of 63 PSC/IPAA patients were studied, including 19 patients with OLT and 44 patients without OLT. Fifty patients (79.4%) had CARP. In both univariable and multivariable analyses (adjusting for OLT status), none of the variables studied was associated significantly with CARP (P > .20). All 7 patients (100%) with IPAA-then-OLT were diagnosed as having CARP, of whom 4 developed CARP before OLT, which persisted after OLT, and 3 had CARP after OLT. Of 12 patients with OLT-then-IPAA, 7 (58.3%) developed CARP. The frequency of CARP in OLT-then-IPAA was statistically significantly lower than that in IPAA-then-OLT (58.3% vs 100%; P = .047).

CONCLUSIONS

CARP is common in patients with ulcerative colitis and PSC. OLT in these patients may not affect the frequency of CARP in general and appears not to alter the disease course of pre-existing CARP. However, in a subset of patients, OLT might reduce the risk for the development of de novo CARP.

Irritable pouch syndrome is associated with depressiveness and can be differentiated from pouchitis by quantification of mucosal levels of proinflammatory gene transcripts

BACKGROUND

Pouchitis and irritable pouch syndrome (IPS) are 2 of the most frequent sequelae of ileal pouch-anal anastomosis (IPAA) after restorative proctocolectomy in patients with ulcerative colitis. These complications can compromise the gain in health-related quality of life (HRQOL) substantially. The pathophysiological mechanisms underlying IPS and the predictors of HRQOL in IPS have not been studied so far.

METHODS

In IPAA patients in remission (n = 10), patients with pouchitis (n = 18) and patients with IPS (n = 15) symptoms, endoscopical and histological patterns, anxiety and depressiveness (Hospital Anxiety and Depression Scale HADS), and HRQOL scores (Inflammatory Bowel Disease Questionnaire, IBDQ-D) were assessed. Mucosal expression of 5 proinflammatory gene transcripts (MRP-14, IL-1beta, IL-8, MIP-2alpha, and MMP-1) were quantified using real-time polymerase chain reaction.

RESULTS

Clinical symptoms and HRQOL differed significantly (P < 0.01) between patients in remission on the one hand and those with pouchitis or IPS on the other. However, between IPS and pouchitis no such differences could be found. Depressiveness scores differed between IPS and patients in remission (P = 0.05). HRQOL in IPS was predicted by depressiveness (P < 0.001). Cytokine transcripts discriminated between pouchitis and IPS (P < 0.01), whereas between IPS patients and asymptomatic patients no such differences were observed.

CONCLUSIONS

Patients with IPS and pouchitis cannot be differentiated by clinical symptoms or HRQOL, which is associated with depressiveness in IPS patients. IPS is a noninflammatory sequela in IPAA patients that shares clinical features with IBD. Quantification of mucosal proinflammatory gene transcripts differentiates objectively and simply between IPS and pouchitis.

Pouchitis

While restorative proctocolectomy with ileal pouch-anal anastomosis has significantly improved the quality of life in patients with underlying ulcerative colitis who require surgery, complications can occur. Pouchitis as the most common long-term complication represents a spectrum of disease processes ranging from acute, antibiotic-responsive type to chronic antibiotic-refractory entity. Accurate diagnosis using a combined assessment of symptoms, endoscopy and histology and the stratification of clinical phenotypes is important for treatment and prognosis the disease. The majority of patients respond favorably to antibiotic therapy. However, management of chronic antibiotic-refractory pouchitis remains a challenge.