Adverse events of thiopurine immunomodulators in patients with inflammatory bowel disease

Exploring the link: Porto-sinusoidal vascular disorder and inflammatory bowel disease - A comprehensive narrative review

Porto-sinusoidal vascular disorder (PSVD) encompasses a group of vascular disorders characterized by lesions involving the portal venules and sinusoids, independent of the presence of portal hypertension (PH), and for which liver biopsy is essential for diagnosis. PSVD has been shown to be common in patients with immune-mediated diseases, including inflammatory bowel disease (IBD). The association between PSVD and the use of thiopurines and thioguanine in patients with IBD has been well established. In addition, research suggests an association between PSVD and IBD, even in cases where patients haven't been exposed to specific medications, probably related to changes in intestinal permeability. The identification and management of patients with known IBD and PSVD is a challenge for gastroenterologists. This narrative review aims to summarize the currently available data on the association between IBD and PSVD and provide practical suggestions for the management of this group of patients.

Early thiopurine maintenance is associated with reduced proximal disease progression and colectomy rate in ulcerative colitis

BACKGROUND

Thiopurines effectively maintain remission in ulcerative colitis patients. Whether early initiation of thiopurines after ulcerative colitis diagnosis decreases proximal disease progression and colectomy rates is not known.

METHODS

We conducted a cohort study of ulcerative colitis subjects recruited from 1970 to 2009. Early thiopurine maintenance was defined as commencement of azathioprine or mercaptopurine within 5 years of diagnosis and maintenance for at least 6 months. Propensity score matching was conducted to correct for confounders influencing early thiopurine introduction. Outcomes of interest were colectomy rate and endoscopic proximal disease extension.

RESULTS

982 consecutive ulcerative colitis subjects (12 879 patient-years) were recruited with 116 requiring colectomy. Thiopurines initiation and maintenance increased over time with median time to thiopurine commencement decreasing from 23 years in the first decade to 2 years in the last decade (P < 0.0001). Multivariate analysis showed that early thiopurine maintenance significantly decreased the need for colectomy [hazard ratio, 0.13; 95% confidence interval (CI):0.03-0.55; P = 0.006]. The number of subjects needed to be treated to reduce one colectomy at 5 and 10 years was 18 (95% CI, 16- 36) and 12 (95% CI, 11-25). After propensity score matching, early thiopurine maintenance was significantly associated with decreased colectomy (hazard ratio, 0.10; 95% CI, 0.03-0.43; P = 0.002) and proximal progression of disease extent (hazard ratio, 0.26; 95% CI, 0.10-0.78; P = 0.015).

CONCLUSION

Early thiopurine maintenance for >6 months is significantly associated with reduced colectomy and proximal progression of disease extent in ulcerative colitis.

Pharmacotherapy of inflammatory bowel diseases: efficacy performance and safety management

Treatment of inflammatory bowel diseases IBD (Crohns disease, ulcerative colitis) is aimed at achieving clinical, endoscopic and histological remission, minimizing surgical complications, and ensuring a normal quality of life. However, the use of medical treatment is potentially associated with various adverse events, among which infectious complications, malignant neoplasms, as well as myelotoxicity, hepatotoxicity, skin lesions and others. The risk of side effects depends on the type of drug therapy (5-aminosalicylates, thiopurines, biologicals, etc.), the duration of treatment, the presence of extra-intestinal manifestations, etc. The article provides an overview of data on both the effectiveness and frequency of various side effects of the main classes of drugs in IBD, presents methods of investigation which can predict the effectiveness and development of side effects, the implementation of which can be considered as a variant of personalized therapy in IBD.

Inflammatory Bowel Diseases Elevate the Risk of Developing Acute Pancreatitis: A Meta-analysis

OBJECTIVES

Increasing data suggest that acute pancreatitis (AP) occurs more frequently among patients with inflammatory bowel diseases (IBDs) than in the non-IBD population; however, currently no comprehensive meta-analysis is available.

METHODS

Systematic literature search was conducted in 4 major databases. We included observational studies sampling from the general population. Basic study characteristics and crude incidences of AP were extracted. Pooled odds ratios (ORs) with 95% confidence interval (CIs) were calculated using the random-effects model. Subgroups were set up by Crohn disease and ulcerative colitis. Heterogeneity was tested with I statistics.

RESULTS

Eight studies were eligible for the analysis. The odds of AP were 3 times higher in IBD (OR, 3.11; 95% CI, 2.93-3.30; I, 0.0%), significantly higher in Crohn disease than in ulcerative colitis (P < 0.001; OR, 4.12 vs OR, 2.61; I, 0.0%). The pooled annual incidence of AP in IBD was 210/100,000 person-years (95% CI, 84-392/100,000 person-years; I, 98.66%).

CONCLUSIONS

We confirmed that IBD elevates the risk of AP and of 100,000 IBD patients 210 AP cases are to be expected annually. Therefore, it is important to include pancreatic enzyme level measurements and radiological investigations in the workup of IBD patients with acute abdominal pain.

Comorbidities Rather Than Age Are Associated With the Use of Immunomodulators in Elderly-onset Inflammatory Bowel Disease

BACKGROUND AND AIM

The use of immunomodulators (IMs) is often avoided in elderly patients with inflammatory bowel disease (IBD) due to concerns about complications. Our aim is to compare the use of IMs in elderly and younger patients with Crohn's disease (CD) or ulcerative colitis (UC) and identify markers that predict their use.

METHODS

In this retrospective cohort study, patients diagnosed with IBD from 1970 to 2009 were recruited from the "Sydney IBD Cohort." Patients diagnosed at age 60 years old or older and between 16 and old 40 years were classified as "elderly-onset" and "young-onset" respectively.

RESULTS

A total of 255 elderly-onset patients (115 CD, 140 UC) and 1244 young-onset patients (657 CD, 587 UC) were recruited. Most elderly-onset patients had colonic CD (61.4%), whereas young-onset patients had predominantly ileocolonic CD (42.8%, P < 0.0001). Left-sided UC was the most common disease localization for both elderly-onset (52.1%) and young-onset patients (42.2%, P = 0.013). The cumulative probability of IM exposure at 5 years post-diagnosis was significantly less in elderly-onset patients compared with young-onset patients for CD (20.0% vs 33.4%, P = 0.0002) and UC (7.8% vs 13.4%, P = 0.0007). Age at diagnosis was not associated with the time to IMs introduction. Charlson Comorbidity Index was shown to delay IM introduction in CD (hazard ratio [HR] 0.863; 95% CI, 0.787-0.946; P = 0.002) and UC (HR 0.807; 95% CI, 0.711-0.917; P = 0.001). Early IM use was associated with reduced need for abdominal and perianal surgery in CD (HR 0.177; 95% CI, 0.089-0.351; P < 0.0001).

CONCLUSIONS

Comorbidity and not age at diagnosis is associated with IM introduction. Early IM is associated with reduced surgery in both young- and elderly-onset CD but not UC.

Tolerability profile of thiopurines in inflammatory bowel disease: a prospective experience

OBJECTIVES

The occurrence of thiopurine-related adverse events (AEs) may complicate the management of patients with inflammatory bowel disease (IBD). We aimed to evaluate the tolerability of thiopurines in a current IBD setting.

MATERIALS AND METHODS

All consecutive patients who started a treatment with azathioprine (AZA) from January 2010 to March 2016 were entered in a prospectively maintained database, and the AEs which led to the permanent discontinuation of the drug were reported.

RESULTS

Two hundred and fifty three patients were included. Median total follow-up was 32 months (range: 0.2-75 months). At the end of the study, AZA was discontinued in 160 patients (63.2%). The main reason leading to drug withdrawal was the occurrence of AEs (109/160 patients [68.1%]; cumulative incidence among the entire cohort: 43.1%). Overall, the most frequent AEs leading to treatment withdrawal were nausea (31/253 patients, 12.3%) and subjective symptoms, i.e., poorly defined side effects such as fatigue, headache and muscle pain (20/253 patients, 7.9%). Among the 109 AZA-intolerant patients, a switch to 6-mercaptopurine (6-MP) was performed in 44 cases (40.4%). At the end of follow-up, 6-MP was discontinued in 35/44 patients (79.5%), mostly due to AEs (29/35 patients, 82.8%). Azathioprine-induced hepatic and pancreatic toxicity was associated with male gender (p = .01 and p = .03, respectively), and occurrence of nausea with Crohn's disease (p = .04).

CONCLUSIONS

Our real-life prospective cohort showed the higher cumulative incidence of thiopurine withdrawal due to AEs reported to date. Switching from AZA to 6-MP was often ineffective.

Thiopurine Prodrugs Mediate Immunosuppressive Effects by Interfering with Rac1 Protein Function

6-Thiopurine (6-TP) prodrugs include 6-thioguanine and azathioprine. Both are widely used to treat autoimmune disorders and certain cancers. This study showed that a 6-thioguanosine triphosphate (6-TGTP), converted in T-cells from 6-TP, targets Rac1 to form a disulfide adduct between 6-TGTP and the redox-sensitive GXXXXGK(S/T)C motif of Rac1. This study also showed that, despite the conservation of the catalytic activity of RhoGAP (Rho-specific GAP) on the 6-TGTP-Rac1 adduct to produce the biologically inactive 6-thioguanosine diphosphate (6-TGDP)-Rac1 adduct, RhoGEF (Rho-specific GEF) cannot exchange the 6-TGDP adducted on Rac1 with free guanine nucleotide. The biologically inactive 6-TGDP-Rac1 adduct accumulates in cells because of the ongoing combined actions of RhoGEF and RhoGAP. Because other Rho GTPases, such as RhoA and Cdc42, also possess the GXXXXGK(S/T)C motif, the proposed mechanism for the inactivation of Rac1 also applies to RhoA and Cdc42. However, previous studies have shown that CD3/CD28-stimulated T-cells contain more activated Rac1 than other Rho GTPases such as RhoA and Cdc42. Accordingly, Rac1 is the main target of 6-TP in activated T-cells. This explains the T-cell-specific Rac1-targeting therapeutic action of 6-TP that suppresses the immune response. This proposed mechanism for the action of 6-TP on Rac1 performs a critical role in demonstrating the capability to design a Rac1-targeting chemotherapeutic agent(s) for autoimmune disorders. Nevertheless, the results also suggest that the targeting action of other Rho GTPases in other organ cells, such as RhoA in vascular cells, may be linked to cytotoxicities because RhoA plays a key role in vasculature functions.

Probing the Association of Pancreatitis in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) has been increasingly diagnosed in children and adults. Similarly, acute and chronic pancreatitis are increasingly prevalent conditions with potentially devastating consequences. There is a growing body of literature linking these 2 conditions. The purpose of this review is to provide a comprehensive outline of the association between IBD and pancreatitis and to explore their putative pathophysiology. Based on the collective reports, 2 outstanding reasons for pancreatitis in patients with IBD are medications and IBD complications.

Clinical predictors of thiopurine-related adverse events in Crohn's disease

AIM: To determine the incidence and predictors of thiopurine-related adverse events.

METHODS: Subjects with Crohn’s disease who were followed in the Alberta Inflammatory Bowel Disease Consortium patient database registry were identified. Retrospective chart review was conducted between August 5^th, 2010 and June 1^st, 2012. We collected data on: age at diagnosis; sex; disease location and behaviour at time of prescribing thiopurine; perianal fistulising disease at or prior to thiopurine prescription; smoking status at time of thiopurine prescription, use of corticosteroid within 6 mo of diagnosis; dosage, age at onset, and cessation of 5-aminosalicyclic acid (5-ASA); anti-tumour necrosis factor medication exposure and intestinal resection before thiopurine prescription. The primary outcome of interest was the first adverse event that led to discontinuation of the first thiopurine medication used. Logistic regression models were used to associate clinical characteristics with outcomes after adjusting for potential confounders. Risk estimates were presented as odds ratios (OR) with 95% CI. Effect modification by age and sex were explored.

RESULTS: Our cohort had a median follow-up duration of 5.8 years [interquartile range (IQR 25^th-75^th) 2.7-9.1]. Thiopurine therapy was discontinued in 31.3% of patients because of: hypersensitivity reactions (7.1%), acute pancreatitis (6.2%), gastrointestinal intolerance (5.4%), leucopenia (3.7%), hepatotoxicity (3.4%), infection (1.1%) and other reasons (4.3%). A higher incidence of thiopurine withdrawal was observed in patients over the age of 40 (39.4%, P = 0.007). A sex-by-age interaction (P = 0.04) was observed. Females older than 40 years of age had an increased risk of thiopurine discontinuation due to an adverse event (age above 40 vs age below 40, adjusted OR = 2.8; 95%CI: 1.4-5.6). In contrast, age did not influence thiopurine withdrawal in males (age above 40 vs below 40, adjusted OR = 0.9; 95%CI: 0.4-2.1). Other clinical variables (disease location and phenotype, perianal disease, smoking history, history of intestinal resection and prior 5-ASA or corticosteroid use) were not associated with an increased risk an adverse event leading to therapy cessation.

CONCLUSION: Thiopurine withdrawal due to adverse events is commoner in women over the age of 40 at prescription. These findings need to be replicated in other cohorts.

Efficacy of Thiopurines in Biologic-Naive Japanese Patients With Crohn's Disease: A Single-Center Experience

Background/Aims

Early use of biologics in patients with Crohn's disease (CD) improves quality of life. However, the effects of the early use of immunomodulators on long-term outcomes remain unclear. This study aimed to evaluate the effects of immunomodulators in patients with CD.

Methods

Between January 2004 and December 2011, 47 biologic-naive CD patients treated with thiopurines alone for remission maintenance were analyzed. The patients were classified into 2 groups depending on the presence or absence of digestive complications. We evaluated the efficacy of and predictive factors for thiopurine use for remission maintenance.

Results

The cumulative relapse rates at 24 and 60 months were 13.7% and 35.4%, respectively. Regarding patient characteristics, there was a significant difference in patient history of surgery between the non-relapse and relapse groups (P=0.021). The cumulative relapse rate was lower in patients without a history of surgery than in those with such a history (27.2% and 52.9% at 60.0 months, respectively). Multivariate analysis suggested that the prevalence of stricturing and penetrating complications is an independent factor for relapse. The cumulative relapse rate in patients without a history of surgery was significantly lower in the non-stricturing and non-penetrating group than in the stricturing and penetrating group (11.8% at 85.0 months vs. 58.5% at 69.0 months; P=0.036).

Conclusions

Thiopurine use might be beneficial for the long-term maintenance of remission in biologic-naive Crohn's disease patients without digestive complications and a history of surgery.

Inflammatory bowel disease and the elderly: a review

Inflammatory bowel disease among the elderly is common, with growing incident and prevalence rates. Compared with younger IBD patients, genetics contribute less to the pathogenesis of older-onset IBD, with dysbiosis and dysregulation of the immune system playing a more significant role. Diagnosis may be difficult in older individuals, as multiple other common diseases can mimic IBD in this population. The clinical manifestations in older-onset IBD are distinct, and patients tend to have less of a disease trajectory. Despite multiple effective medical and surgical treatment strategies for adults with Crohn's disease and ulcerative colitis, efficacy studies typically have excluded older subjects. A rapidly ageing population and increasing rates of Crohn's and ulcerative colitis make the paucity of data in older adults with IBD an increasingly important clinical issue.

Thiopurine monitoring in children with inflammatory bowel disease: a systematic review

AIMS

The aim was to systematically review the evidence on the clinical usefulness of thiopurine metabolite and white blood count (WBC) monitoring in the assessment of clinical outcomes in children with inflammatory bowel disease (IBD).

METHODS

Medline, Embase, Cochrane Central Register of controlled trials and http://www.clinicaltrials.gov were screened in adherence to the PRISMA statement by two independent reviewers for identification of eligible studies. Eligible studies were randomized controlled trials (RCTs), cohort studies and large case series of children with inflammatory bowel disease (IBD) (<18 years) who underwent monitoring of thiopurine metabolites and/or WBC.

RESULTS

Fifteen papers were identified (n = 1026). None of the eligible studies were RCTs. High 6-thioguanine nucleotide (6TGN) concentrations were not consistently associated with leucopenia. Leucopenia was not associated with achievement of clinical remission. A positive but not consistent correlation between 6TGN and clinical remission was reported. Haematological toxicity could not be reliably assessed with 6TGN measurements only. A number of studies supported the use of high 6-methylmercaptopurine ribonucleotides (6MMPR) as an indicator of hepatotoxicity. Low thiopurine metabolite concentration may be indicative of non-compliance.

CONCLUSION

Thiopurine metabolite testing does not safely predict clinical outcome, but may facilitate toxicity surveillance and treatment optimization in poor responders. Current evidence favours the combination of thiopurine metabolite/WBC monitoring and clinic follow-up for prompt identification of haematologic/hepatic toxicity safe dose adjustment, and treatment modification in cases of suboptimal clinical outcome or non-compliance. Well designed RCTs for the identification of robust surrogate markers of thiopurine efficacy and toxicity are required.

Natural history of pancreatic involvement in paediatric inflammatory bowel disease

BACKGROUND

Few case reports describe the clinical features of pancreatic involvement in inflammatory bowel disease.

AIM

To investigate prevalence and disease course of inflammatory bowel disease children with pancreatitis and with exclusive hyperamylasemia and hyperlipasemia.

METHODS

We used a web-registry to retrospectively identify paediatric inflammatory bowel disease patients with hyperamylasemia and hyperlipasemia. Participants were re-evaluated at 6 months and 1 year.

RESULTS

From a total of 649 paediatric patients, we found 27 with hyperamylasemia and hyperlipasemia (4.1%). Eleven patients (1.6%) fulfilled diagnostic criteria for acute pancreatitis. Female gender was significantly associated with acute pancreatitis (p=0.04). Twenty-five children (92.5%) had colonic disease. At 6 months 1/11 children with acute pancreatitis (9%) showed acute recurrent pancreatitis, while 1 patient (9%) had persistent hyperamylasemia and hyperlipasemia. At 12 months, 1 patient showed chronic pancreatitis (9.1%). Of the 16 children with exclusive hyperamylasemia and hyperlipasemia, 4 developed acute pancreatitis (25%), while 1 patient (6.2%) still presented exclusive hyperamylasemia and hyperlipasemia at 6 months. At 12 months, 11/16 patients (68.7%) reached a remission of pancreatic involvement, whereas 5 remaining patients (32.3%) had persistent hyperamylasemia and hyperlipasemia.

CONCLUSIONS

In inflammatory bowel disease children, acute pancreatitis is more common in colonic disease and in female gender. Pancreatic function should be monitored, considering that pancreatic damage may evolve.

Azathioprine is essential following cyclosporine for patients with steroid-refractory ulcerative colitis

AIM: To evaluate long-term prognosis following cyclosporine treatment by examining the rate of surgery avoidance among cyclosporine responders.

METHODS: We retrospectively reviewed clinical records for 29 patients diagnosed with severe steroid-refractory ulcerative colitis in our hospital from August 1997 to August 2008 and treated with cyclosporine by continuous intravenous infusion. All patients were treated with intravenous corticosteroids for more than 5 d prior to cyclosporine therapy. Administration was continued for up to 21 d under serum monitoring to maintain cyclosporine levels between 400 and 600 ng/mL. Clinical activity was assessed before and after cyclosporine therapy using the clinical activity index score, with a reduction of ≥ 5 considered to indicate a response. Among responders, we defined cases not requiring surgery for more than 5 years as exhibiting long-term efficacy of cyclosporine. Factors considered to be possibly predictive of long-term efficacy of cyclosporine were sex, age, disease duration, clinical activity index score, C-reactive protein level, hemoglobin level, disease extent, endoscopic findings, and clinical course.

RESULTS: Cyclosporine was not discontinued due to side effects in any patient. Nineteen (65.5%) of 29 patients were considered responders. A statistically significant (P = 0.004) inverse association was observed between an endoscopic finding of “mucosal bleeding” and responsive cases. Fifteen (9 males, 6 females) of these 19 patients were followed for 5 years or more, of whom 9 (60%) exhibited long-term efficacy of cyclosporine. Of the 10 non-responders, 9 (90%) underwent surgery within 6 mo of cyclosporine therapy. None of the following factors had a significant impact on the long-term efficacy of cyclosporine: sex, age, duration of disease, clinical activity index score, C-reactive protein level, hemoglobin level, extent of disease, endoscopic findings, or clinical course. In contrast, a significant association was observed for maintenance therapy with azathioprine after cyclosporine therapy (P = 0.0014).

CONCLUSION: Maintenance therapy with azathioprine might improve the long-term efficacy of continuously infused cyclosporine for severe steroid-refractory ulcerative colitis patients.

Stopping, continuing, or restarting immunomodulators and biologics when an infection or malignancy develops

Thiopurines and biologics are being used earlier and more frequently for the treatment of Crohn's disease and ulcerative colitis. These medications are generally well tolerated and usually do not require cessation due to a side effect. Rare but serious infections and cancers may develop in patients on these immunosuppressants. Evidence-based data are lacking to guide physicians on whether continuing or stopping thiopurines and biologics is necessary and, when a side effect does occur, if and when restarting these medications is feasible. The aim of this review was to outline the infectious and malignant complications that may develop on these treatments and to provide recommendations for continuing, stopping, and restarting thiopurines and biologics once a patient develops a treatment-related complication. These are not formal guidelines and should not replace individualized care by the treating physician.

Review article: the association between nodular regenerative hyperplasia, inflammatory bowel disease and thiopurine therapy

BACKGROUND

Nodular regenerative hyperplasia (NRH) is increasingly being recognised in patients with inflammatory bowel disease (IBD). However, the pathogenesis and incidence of NRH in IBD, and the putative roles played by azathioprine (AZA), mercaptopurine (MP), or tioguanine (TG) remain unclear.

AIMS

To summarise the data on the association between NRH and thiopurine therapy in patients with IBD.

METHODS

A literature search was performed in PubMed and MEDLINE databases using the keywords 'nodular regenerative hyperplasia AND (inflammatory bowel disease OR Crohn's disease OR ulcerative colitis) AND (azathioprine OR mercaptopurine OR tioguanine OR thioguanine).' No time limit was placed on studies included.

RESULTS

Inflammatory bowel disease patients treated with AZA have a cumulative incidence of NRH of approximately 0.6% and 1.28% at 5 and 10 years, respectively, whereas those treated with high-dose TG (>40 mg/day) have a frequency of NRH of up to 62%, which is higher in patients with elevated liver enzymes and/or thrombocytopaenia than those without these abnormalities (frequency 76% vs. 33%). Conversely, low-dose TG therapy (<20 mg/day) is relatively safe, with no cases of NRH observed. NRH has also been found in 6% of operated thiopurine-naïve IBD patients. Male gender, older age, and stricturing disease/small bowel resection have been consistently identified as high-risk factors for NRH.

CONCLUSIONS

The pathogenesis of nodular regenerative hyperplasia in patients with IBD is complex and multifactorial involving disease-specific, genetic and iatrogenic risk factors. Clinicians should maintain a high index of suspicion for diagnosing nodular regenerative hyperplasia, especially in IBD patients with high-risk factors on thiopurine therapy, regardless of the presence of laboratory abnormalities.

A trial of mercaptopurine is a safe strategy in patients with inflammatory bowel disease intolerant to azathioprine: an observational study, systematic review and meta-analysis

BACKGROUND

Thiopurines maintain remission and modify disease course in inflammatory bowel disease. Use is limited by intolerance and subsequent drug withdrawal in approximately 17% of patients treated with azathioprine. Previous case series have addressed the success rates of re-treatment with mercaptopurine in these individuals.

AIMS

To determine the rate of tolerance when trialling mercaptopurine in azathioprine-intolerant patients and the factors predictive of success, and to perform a systematic review and meta-analysis of these data with other published data sets.

METHODS

A retrospective observational study of 149 patients with IBD (82 with Crohn's disease and 67 with ulcerative colitis) previously intolerant of azathioprine subsequently treated with mercaptopurine was performed. A meta-analysis was undertaken of all published studies of mercaptopurine use in azathioprine-intolerant patients (455 patients in 11 included studies).

RESULTS

Mercaptopurine was tolerated by 58% of azathioprine-intolerant patients in the Edinburgh cohort. In the meta-analysis, 68% tolerated mercaptopurine. A higher proportion of those in the meta-analysis with GI toxicity (62%) or hepatotoxicity (81%) were able to tolerate mercaptopurine than those with flu-like illness (36%). Among those patients who ceased mercaptopurine for further adverse effects, 59% experienced the same adverse effect as they had with azathioprine.

CONCLUSIONS

This meta-analysis shows that switching to mercaptopurine is a safe therapeutic strategy for over two-thirds of azathioprine-intolerant patients and may help optimise immunomodulatory therapy in inflammatory bowel disease. A trial of mercaptopurine should be attempted in IBD patients (except those with acute pancreatitis or bone marrow aplasia) before considering thiopurine intolerance.

Hepatopancreatobiliary manifestations of inflammatory bowel disease

Inflammatory bowel disease (IBD) is frequently associated with extraintestinal manifestations such as hepatopancreatobiliary manifestations (HPBMs), which include primary sclerosing cholangitis (PSC), pancreatitis, and cholelithiasis. PSC is correlated with IBD, particularly ulcerative colitis (UC); 70-80% of PSC patients in Western countries and 20-30% in Japan have comorbid UC. Therefore, patients diagnosed with PSC should be screened for UC by total colonoscopy. While symptoms of PSC-associated UC are usually milder than PSC-negative UC, these patients have a higher risk of colorectal cancer, particularly in the proximal colon. Therefore, regular colonoscopy surveillance is required regardless of UC symptoms. Administration of 5-aminosalicylic acid or ursodeoxycholic acid may prevent colorectal cancer and cholangiocarcinoma. While PSC is diagnosed by diffuse multifocal strictures on cholangiography, it must be carefully differentiated from immunoglobulin G4 (IgG4)-associated cholangitis, which shows a similar cholangiogram but requires different treatment. When PSC is suspected despite a normal cholangiogram, the patient may have small-duct PSC, which requires a liver biopsy. IBD patients have a high incidence of acute and chronic pancreatitis. Most cases are induced by cholelithiasis or medication, although some patients may have autoimmune pancreatitis (AIP), most commonly type 2 without elevation of serum IgG4. AIP should be accurately identified based on characteristic image findings, because AIP responds well to corticosteroids. Crohn's disease is frequently associated with gallstones, and several risk factors are indicated. HPBMs may influence the management of IBD, therefore, accurate diagnosis and an appropriate therapeutic strategy are important, as treatment depends upon the type of HPBM.