Fatal infectious mononucleosis: a severe complication in the treatment of Crohn's disease with azathioprine

Impact of Epstein-Barr virus infection in patients with inflammatory bowel disease

A high prevalence of Epstein-Barr virus (EBV) infection in patients with inflammatory bowel disease (IBD) has been reported in many case reports and studies; thus, the association between EBV and IBD has gained increasing attention. Patients with IBD are at an increased risk of opportunistic EBV infection owing to the common use of immunomodulators. EBV infection in IBD patients can cause various complications, including superimposed viral colitis, which is associated with chronicity, exacerbation, and poor prognosis of refractory IBD, and can induce progression to lymphoproliferative disorders, such as EBV-positive mucocutaneous ulcer (EBVMCU), lymphomatoid granulomatosis (LYG), hemophagocytic lymphohistiocytosis (HLH) and diffuse large B-cell lymphoma (DLBCL). It has been suggested to screen for EBV before initiating immunosuppressive therapy and monitor the status of EBV infection in patients with IBD, especially those who are EBV-seronegative and have a risk of primary EBV infection. Clinicians should also be careful of misdiagnosing IBD and EBV-associated lymphoproliferative diseases due to similarities in both clinical symptoms and endoscopic manifestations. Withdrawal of immunosuppressants has been shown to be an effective strategy to achieve remission of disease at the time of EBV diagnosis, but antiviral therapy remains controversial. The present review aims to describe the characteristics of the complications caused by EBV infection and generalize the recent research progress on and challenges caused by EBV infection in IBD patients. The literature for writing this review was collected from 'PubMed' research engine. The keywords 'inflammatory bowel disease and Epstein-Barr virus' or 'ulcerative colitis and Epstein-Barr virus' or 'Crohn's disease and Epstein-Barr virus' were used to collect the literature and relevant papers were collected to help writing this review.

Multicenter, cross-sectional, observational study on Epstein-Barr viral infection status and thiopurine use by age group in patients with inflammatory bowel disease in Japan (EBISU study)

BACKGROUND

The Epstein-Barr virus (EBV) infection status in patients with inflammatory bowel disease (IBD), particularly those using thiopurines, may be associated with the risk of lymphoproliferative disorder and hemophagocytic lymphohistiocytosis. This was the first multicenter survey of EBV infection in Japanese patients with IBD. Factors related to the EBV infection status were also investigated.

METHODS

Five tertiary institutions in Japan participated in this study to examine pediatric and adult patients with IBD. Serum EBV anti-viral capsid antigen (VCA) IgG, EBV anti-VCA IgM, and anti-EBV nuclear antigen-antibody were measured in 495 patients with IBD. The patients' information was obtained from their medical records. Prior EBV infection was defined as anti-VCA IgM negativity and anti-VCA IgG positivity (UMIN000033004).

RESULTS

The patients' median age was 25 years (range 0-92 years). Of the 495 patients, nine were anti-VCA IgM-positive and 354 were anti-VCA IgG-positive (seroprevalence: 72.8%). The proportion of patients with prior EBV infection was 0% for those aged < 5 years, < 60% for those aged < 30 years, and > 90% for those aged > 30 years. The proportion of EBV-uninfected patients using thiopurines was 28.4% (52/183) for all patients and 51.8% (44/85) for pediatric patients. Age was significantly associated with anti-VCA IgG seropositivity (p < 0.01, odds ratio: 0.902, 95% confidence interval: 0.880-0.925). No cases of lymphoproliferative disorder, hemophagocytic lymphohistiocytosis, or chronic active EBV infection were reported.

CONCLUSIONS

Approximately 30% of Japanese patients with IBD were EBV-uninfected, including those using thiopurines. Age was a significant factor for anti-VCA IgG seropositivity.

Viral infections in inflammatory bowel disease: Tips and tricks for correct management

Over the past decades, the treatment of inflammatory bowel diseases (IBD) has become more targeted, anticipating the use of immune-modifying therapies at an earlier stage. This top-down approach has been correlated with favorable short and long-term outcomes, but it has also brought with it concerns regarding potential infectious complications. This large IBD population treated with immune-modifying therapies, especially if combined, has an increased risk of severe infections, including opportunistic infections that are sustained by viral, bacterial, parasitic, and fungal agents. Viral infections have emerged as a focal safety concern in patients with IBD, representing a challenge for the clinician: they are often difficult to diagnose and are associated with significant morbidity and mortality. The first step is to improve effective preventive strategies, such as applying vaccination protocols, adopt adequate prophylaxis and educate patients about potential risk factors. Since viral infections in immunosuppressed patients may present atypical signs and symptoms, the challenges for the gastroenterologist are to suspect, recognize and diagnose such complications. Appropriate treatment of common viral infections allows us to minimize their impact on disease outcomes and patients’ lives. This practical review supports this standard of care to improve knowledge in this subject area.

A novel single-tube multiplex real-time PCR assay for genotyping of thiopurine intolerance-causing variant NUDT15 c.415C>T

Thiopurines are commonly used in the treatment of acute lymphoblastic leukaemia and autoimmune conditions, can be limited by myelosuppression. The NUDT15 c.415C>T variant is strongly associated with thiopurine-induced myelosuppression, especially in Asians. The purpose of this study was to develop a fast and reliable genotyping method for NUDT15 c.415C>T and investigate the polymorphic distribution among different races in China. A single-tube multiplex real-time PCR assay for NUDT15 c.415C>T genotyping was established using allele-specific TaqMan probes. In 229 samples, the genotyping results obtained through the established method were completely concordant with those obtained by Sanger sequencing. The distributions of NUDT15 c.415C>T among 173 Han Chinese, 48 Miaos, 40 Kazakhs, and 40 Kirghiz were different, with allelic frequencies of 0.06, 0.02, 0.07, and 0, respectively. This method will provide a powerful tool for the implementation of the genotyping-based personalized prescription of thiopurines in clinical settings.

A nearly fatal primary Epstein-Barr virus infection associated with low NK-cell counts in a patient receiving azathioprine: a case report and review of literature

Background

Symptomatic primary Epstein-Barr virus infection is a usually self-limiting illness in adolescents. We present a case of an adolescent who had been receiving azathioprine for inflammatory bowel disease for four years and developed a life-threatening primary Epstein-Barr virus infection successfully treated with rituximab.

Case presentation

An 11-year-old girl presented with chronic, bloody diarrhea. Endoscopic biopsies confirmed a diagnosis of chronic ulcerative colitis with features of Crohn’s disease. Azathioprine was initiated after one year due to active colitis. She responded well and remission was achieved. At the age of 16 years she developed a life-threatening Epstein-Barr virus infection including severe multiple organ failure and was critically ill for 4 weeks in the intensive care unit. Natural killer cells were virtually absent in the lymphocyte subset analysis. Azathioprine was stopped on admission. She was initially treated with corticosteroids, acyclovir and intravenous immunoglobulin. Approximately 30 days after admission, she developed signs of severe hepatitis and pneumonitis and received weekly rituximab infusions for 8 weeks. Primary immunodeficiency was excluded by whole exome sequencing in two independent laboratories. Persistent viremia stopped when the natural killer cell count started to rise, approximately 90 days after the cessation of azathioprine.

Conclusions

We found 17 comparable cases in the literature. None of the previous cases reported in the literature, who had been treated with azathioprine and developed either a severe or a fatal Epstein-Barr virus infection, underwent full genetic and prospective immunological workup to rule out known primary immunodeficiencies. Recently, azathioprine has been shown to cause rather specific immunosuppression, resulting in natural killer cell depletion. Our case demonstrates that slow recovery from azathioprine-induced natural killer cell depletion, 3 months after the stopping of azathioprine, coincided with the clearance of viremia and clinical recovery. Finally, our choice of treating the patient with rituximab, as previously used for patients with a severe immunosuppression and Epstein-Barr virus viremia, appeared to be successful in this case. We suggest testing for Epstein-Barr virus serology before starting azathioprine and measuring natural killer cell counts during the treatment to identify patients at risk of developing an unusually severe primary Epstein-Barr virus infection.

Epstein–Barr virus-associated hemophagocytic syndrome in a patient with ulcerative colitis during treatment with azathioprine: A case report and review of literature

A 19-year-old female was diagnosed with ulcerative colitis when she presented with persistent melena, and has been treated with 5-aminosalicylic acid for 4 years, with additional azathioprine for 2 years at our hospital. The patient experienced high-grade fevers, chills, and cough five d prior to presenting to the outpatient unit. At first, the patient was suspected to have developed neutropenic fever; however, she was diagnosed with Epstein-Barr virus-associated hemophagocytic syndrome (EB-VAHS) upon fulfilling the diagnostic criteria after bone marrow aspiration. When patients with inflammatory bowel disease treated with immunomodulators, such as thiopurine preparations, develop fever, EB-VAHS should be considered in the differential diagnosis.

Update on the Use of Thiopurines and Methotrexate in Inflammatory Bowel Disease

PURPOSE OF REVIEW

The increased use of biologic agents over the past two decades has led to a reappraisal of the role of the immunomodulators (thiopurines and methotrexate) in the treatment of inflammatory bowel disease. The purpose of this review is to summarize recent data on the use of thiopurines and methotrexate either as monotherapy or as part of combination therapy with biologic agents.

RECENT FINDINGS

Recent studies have addressed the need for concomitant immunomodulatory therapy in treatment-naïve patients starting anti-TNF-α therapy, the appropriate dose of the immunomodulator in this setting, the minimum duration of combination therapy, and the possible mechanisms by which immunomodulators enhance the effectiveness of anti-TNF-α agents. Little is known about the role of immunomodulators in combination with agents belonging to other classes of biologic therapies. Recent studies have shown that methotrexate is not effective in inducing or maintaining remission in ulcerative colitis. Finally, several studies have broadened our understanding of the infection and malignancy risks of the immunomodulators. Immunomodulators continue to have a place in the treatment of inflammatory bowel disease. However, with the ever-increasing list of biologic agents, properly positioning the immunomodulators within the overall therapeutic scheme is a complicated task. In order to optimize outcomes, each patient requires an individualized approach, which takes into account risks, benefits, cost, alternatives, and patient preferences.

Specific changes of enteric mycobiota and virome in inflammatory bowel disease

One of the important features of inflammatory bowel disease (IBD) is dysbiosis of the gut microbiota. It has been well documented that changes in the commensal bacterial population are involved in IBD development. However, the function of the fungal and viral communities in IBD remains unclear. Moreover, the optimal treatment for IBD patients with opportunistic infections is still undecided. This review focused on how the enteric mycobiota and virome changes during the pathogenesis of IBD and discussed potential treatment strategies that open new insights into the managements of IBD.

Lymphoproliferative Disorders in Inflammatory Bowel Disease Patients: Is It the Drugs or the Disease

Introduction

Systemic inflammatory diseases are related to an increased risk of lymphoproliferative disorders. Although inflammatory bowel disease (IBD) was also associated with these conditions, population-based studies failed to demonstrate this relationship, and most studies only identified a very small number of cases. In the last few years, concerns arose regarding the role of thiopurines and tumour necrosis factor-alpha (TNF-α)-blocking agents in the development of lymphoma, influencing therapeutic decisions in IBD patients. The aim of this study was to describe a case series of IBD patients who developed a lymphoproliferative disorder in our tertiary referral centre.

Material and Methods

The clinical records of all IBD patients who were observed in our unit between January 2007 and December 2016 were retrospectively reviewed, and IBD subjects who were diagnosed with a lymphoproliferative disorder were selected. Clinical and demographic data regarding both conditions were collected.

Results

Six IBD patients were diagnosed with a lymphoma - 4 Hodgkin lymphomas and 2 B-cell non-Hodgkin lymphomas - of which 3 corresponded to primary colonic lymphomas. Immunohistochemical analysis detected the presence of Epstein-Barr virus in the tumour cells of 2 patients, both of them with Hodgkin lymphomas. Only 2 patients were previously treated with thiopurines or anti-TNF-α drugs; none of the remaining had any history of immunosuppressive treatment.

Discussion and Conclusions

Despite major attention being currently focused on the effect of treatment, which may play the main role in the increased susceptibility to lymphoma in IBD patients, and although it may be difficult to demonstrate, IBD itself may contribute to the development of lymphoproliferative disorders, particularly primary intestinal lymphomas.

Diagnostic and vaccine strategies to prevent infections in patients with inflammatory bowel disease

OBJECTIVES

The treatment of inflammatory bowel disease (IBD) has been revolutionized by the use of immunomodulatory agents. Although these potent drugs are effective in controlling disease activity, they also cause an increased risk of new infections or reactivation of latent infections. On these premises, we aimed to provide guidance on the definitions of immunocompromised patients, opportunistic infections and the risk factors associated with their occurrence in an IBD context, and to suggest the proper screening tests for infectious diseases and the vaccination schedules to perform before and/or during therapy with immunomodulators.

METHODS

All the most recent evidences - filtered by the combined work of gastroenterologists and infectious disease experts - were summarized with the aim to provide a practical standpoint for the physician.

RESULTS

A systematic screening of all infections which may arise during therapy with immunomodulator drugs is necessary in all patients with IBD.

CONCLUSIONS

The ideal timing to perform screening tests and vaccinations is at the diagnosis of the disease, regardless of its severity at onset, because the course of IBD and its treatment may vary over time, and an immunocompromised status may hamper efficacy and/or possibility to perform all necessary vaccines.

Experts Opinion on the Practical Use of Azathioprine and 6-Mercaptopurine in Inflammatory Bowel Disease

The relevance of azathioprine and 6-mercaptopurine therapy in inflammatory bowel disease, Crohn's disease, and ulcerative colitis, has been challenged in recent publications. In this article, a panel of experts gives advice, based on the relevant literature, on indications and practical use of azathioprine/6-mercaptopurine, prevention, and management of drug adverse reactions and special situations such as vaccination, pregnancy, and lactation.

NUDT15 polymorphisms alter thiopurine metabolism and hematopoietic toxicity

Widely used as anticancer and immunosuppressive agents, thiopurines have narrow therapeutic indices owing to frequent toxicities, partly explained by TPMT genetic polymorphisms. Recent studies identified germline NUDT15 variation as another critical determinant of thiopurine intolerance, but the underlying molecular mechanisms and the clinical implications of this pharmacogenetic association remain unknown. In 270 children enrolled in clinical trials for acute lymphoblastic leukemia in Guatemala, Singapore and Japan, we identified four NUDT15 coding variants (p.Arg139Cys, p.Arg139His, p.Val18Ile and p.Val18_Val19insGlyVal) that resulted in 74.4-100% loss of nucleotide diphosphatase activity. Loss-of-function NUDT15 diplotypes were consistently associated with thiopurine intolerance across the three cohorts (P = 0.021, 2.1 × 10(-5) and 0.0054, respectively; meta-analysis P = 4.45 × 10(-8), allelic effect size = -11.5). Mechanistically, NUDT15 inactivated thiopurine metabolites and decreased thiopurine cytotoxicity in vitro, and patients with defective NUDT15 alleles showed excessive levels of thiopurine active metabolites and toxicity. Taken together, these results indicate that a comprehensive pharmacogenetic model integrating NUDT15 variants may inform personalized thiopurine therapy.

Haemophagocytic lymphohistiocytosis in inflammatory bowel disease with virus infection

Patients with inflammatory bowel disease (IBD) are at risk of developing haemophagocytic lymphohistiocytosis (HLH) because of chronic systemic inflammation as well as exposure to immunosuppressive medications. The two main causes of HLH in IBD patients are infection with cytomegalovirus and Epstein-Barr virus. Patients with Crohn's disease are more susceptible to HLH than those with ulcerative colitis. The majority of cases are seen in people receiving an immunosuppressive regimen that included thiopurines.

Epstein-Barr virus (EBV) related acute liver failure: a case series from the US Acute Liver Failure Study Group

PURPOSE

Acute liver failure (ALF) is a rare clinical syndrome associated with a high case fatality rate. Asymptomatic primary infection with Epstein-Barr virus (EBV) is common in the general population while acute hepatitis and jaundice are much less common and ALF has been rarely reported. We reviewed the presenting features as well as clinical outcomes amongst consecutive adults with EBV-related ALF.

METHODS

Amongst the 1,887 adult ALF patients enrolled into the US ALF Study Group from January 1998 to February 2012, there were four patients (0.21 %) with EBV-related ALF. Diagnostic criteria for acute EBV infection included compatible serologies and/or the detection of EBV-encoded RNA (EBER) in liver tissue.

RESULTS

Median patient age was 30 years (range 18-44); 75 % were male, and only 25 % were immunosuppressed. The median presenting ALT was 504 IU/mL (range 156-4,920), median Alk P was 431 (range 136-1,009), and median bilirubin was 17 mg/dL (range 13-22.1). Liver biopsy findings ranged from cholestasis to submassive necrosis with EBER + staining in two of the three samples tested. Although all of the patients were treated with an antiviral agent, two died of ALF, one underwent liver transplantation (LT) and one survived with supportive care and is well at 5 years. A review of the literature identified four additional LT recipients with favorable long-term outcomes.

CONCLUSION

Primary EBV infection accounts for <1 % of consecutive adult ALF cases but is associated with a high case fatality rate. LT is associated with favorable short- and long-term outcomes.

Immunizations in children with inflammatory bowel disease treated with immunosuppressive therapy

The vast majority of patients with inflammatory bowel disease (IBD) will receive immunosuppressive therapy at some point for their disease, whether for the short term (such as a course of corticosteroids) or long term (such as maintenance therapy with immunomodulators or biologics). The systemic immunosuppression places patients at increased risk for infections. Therefore, it is important that patients are up-to-date with immunizations to minimize vaccine-preventable infections. However, the literature shows that the rate of immunization in patients with IBD is low. Ideally, the vaccination status is checked at diagnosis, and patients are immunized with the vaccines they need. Drawing titers is helpful in cases in which vaccination history is unclear or to confirm that titers are at an adequate level in cases in which patients have been vaccinated. Current guidelines recommend that patients with IBD follow the same routine immunization schedule as healthy children, but patients should not be administered live vaccines if they are receiving immunosuppressive therapy. Therefore, it is ideal to administer any necessary vaccinations as early as possible, prior to starting immunosuppressive therapy. Patients may receive inactivated vaccines regardless of immunosuppressive status. The IBD literature suggests that inactivated vaccines are safe and do not worsen disease activity. In general, patients with IBD mount an immune response to vaccines, but the response may be lower if patients are receiving immunosuppressive therapy, especially tumor necrosis factor inhibitors.

Opportunistic infections due to inflammatory bowel disease therapy

The use of biological agents and immunomodulators for inflammatory bowel disease (IBD) has remarkably improved disease management in the current era but at the same time has increased the risk of infectious complications. Patients with IBD on corticosteroids, immunomodulators, and biological agents are considered immunocompromised and are at risk for opportunistic infections. These are infections caused by organisms that take advantage of a weakened immune system, and cause disease, when they ordinarily would cause mild illness or no disease in an immunocompetent host. Risk factors for opportunistic infections include malnutrition, older age, congenital immunodeficiency, HIV infection, chronic diseases, and use of corticosteroids, immunomodulators, and anti-tumor necrosis factor alpha therapy. Apart from immunosuppressive medications and older age, there is only indirect evidence for above risk factors contributing directly to opportunistic infection risk in patients with IBD. Opportunistic infections in patients with IBD include viral infections (herpes viruses, human papillomavirus, influenza virus, and JC virus), bacterial infections (tuberculosis, nocardiosis, Clostridium difficile infection, pneumococcal infection, legionellosis, and listeriosis), fungal infections (histoplasmosis, cryptococcosis, Pneumocystis jirovecii infection, aspergillosis, and candidiasis), and parasite infections (Strongyloides stercoralis). Although these infections lead to high morbidity and mortality, only a minority of patients with IBD develop opportunistic infections. Currently, we lack a test to accurately predict patients at risk of opportunistic infection, and future research needs to focus on biomarkers or predictive models for risk stratification. Until such a test is developed, we need to screen, prevent, diagnose, and treat opportunistic infections in all patients with IBD in a timely manner.

Extra-intestinal malignancies in inflammatory bowel disease: results of the 3rd ECCO Pathogenesis Scientific Workshop (III)

The incidence of lymphoproliferative disorders (LD) is increasing in developed countries. Patients with inflammatory bowel disease (IBD) exposed to thiopurines are at additional risk of three specific forms of LD: Epstein-Barr-Virus-related post-transplant like LD, hepato-splenic T-cell lymphoma and post-mononucleosis lymphoproliferation. The risk of the two latter forms of LD can be reduced when considering specific immunosuppressive strategies in young males. It is still unclear whether the risk of uterine cervix abnormalities is increased in IBD women, irrespective of the use of immunosuppressants. Given the excess risk demonstrated in various other contexts of immunosuppression, it is currently recommended that all women with IBD, particularly those receiving immunosuppressants, strictly adhere to a screening program of cervical surveillance and undergo vaccination against HPV, when appropriate. Patients with IBD receiving immunosuppressants are at increased risk of skin cancers. The risk of non-melanoma skin cancer is notably increased in patients receiving thiopurines. Recent data suggest that the risk of melanoma is mildly increased in patients exposed to anti-TNF therapy. All IBD patients should adhere to a program of sun protection and dermatological surveillance, whose details should take into account the other non-IBD-related risk factors.

Prevalence of Epstein-Barr Virus in a population of patients with inflammatory bowel disease: a prospective cohort study

BACKGROUND

The Epstein-Barr Virus (EBV) is truly prolific, with a prevalence of more than 90% in the adult human population. There are, however, little data available on the prevalence of EBV among patients with Inflammatory Bowel Disease (IBD), a population that is frequently immunosuppressed and thus at risk for severe, often fatal, primary infection.

AIM

To identify the prevalence of EBV in a population of patients with IBD and to compare it with that of the general population.

METHODS

A database of 2500 IBD patients previously followed at the University of Alberta IBD Centre was queried; 60 of these patients were randomly chosen to participate. A total of 220 patients attending the IBD Centre for clinical appointment were also prospectively asked to participate. Participants completed serological testing for VCA-IgM, VCA-IgG and EBNA-IgG, to determine prior EBV exposure.

RESULTS

A total of 263 patients underwent testing. Results for EBV seroprevalence of specific age groups were as follows: 18-20 years (n = 17), 29% seronegative; 21-25 years (n = 31), 29% seronegative; 26-30 years (n = 35), 31-35 years (n = 18) and 36-40 years (n = 25), 100% seropositive. Finally, 3% of those older than 40 (n = 117) were seronegative. EBV seroprevalence was similar for Crohn's disease and ulcerative colitis. Azathioprine was associated with seropositivity (P = 0.048).

CONCLUSION

The prevalence of EBV seronegativity in the IBD population aged 18-25 years was similar to that described in the general population, and above age 25 years, seropositivity approached 100%.

Prevention of infection caused by immunosuppressive drugs in gastroenterology

Immunosuppressive therapy is frequently used to treat gastrointestinal diseases such as inflammatory bowel disease, autoimmune hepatitis, IgG4-related disease (autoimmune pancreatitis and sclerosing cholangitis) and in the post-transplantation setting. These drugs interfere with the immune system. The main safety concern with their use is the risk of infections. Certain infections can be prevented or their impact minimized. Physicians must adopt preventative strategies and should have a high degree of suspicion to recognize infections early and treat appropriately. This article reviews the risk factors for infections, the mechanism of action of immunosuppressive therapy and proposes preventive strategies.

Systematic review: macrophage activation syndrome in inflammatory bowel disease

BACKGROUND

Recently, there have been increasingly frequent reports on the occurrence of macrophage activation syndrome (MAS) in patients with inflammatory bowel disease (IBD). Clinically, MAS is characterized mainly by fever, hepatosplenomegaly, cytopenia, and elevated circulating ferritin and CD25. Mortality, even if diagnosed rapidly, is high.

AIM

To identify all reports on MAS in IBD and to establish data on triggering agents, immunosuppression leading to MAS, and mortality.

METHODS

A language unrestricted search on Pubmed and Scopus relating to the past 30 years was carried out by matching the following search-terms: h(a)emophagocytic lymphohistiocytosis OR h(a)emophagocytic lymphohistiocytic syndrome OR macrophage activation syndrome OR opportunistic infections OR cytomegalovirus OR Epstein-Barr virus AND Crohn's disease OR ulcerative colitis OR inflammatory bowel disease(s).

RESULTS

Fifty cases were identified with an overall mortality of 30%. Virus-related MAS associated with cytomegalovirus or Epstein-Barr virus infections represents the main type of MAS, but in isolated cases bacterial infections precipitated the syndrome. In four cases (8%), a lymphoma was present at the time of MAS diagnosis or developed shortly thereafter. Thiopurine monotherapy was given before MAS onset in 56% of the patients, whereas multiple immunosuppression, including biologics, was administered to 24%.

CONCLUSIONS

In IBD patients, the syndrome appears to be triggered by infections, but genetic susceptibility may contribute to its development. Since immunosuppressive therapy represents the backbone of therapeutic interventions in IBD, with the risk of new, or the reactivation of latent infections, even more frequent cases of macrophage activation syndrome may be expected.

A case of EBV driven haemophagocytic lymphohistiocytosis complicating a teenage Crohn's disease patient on azathioprine, successfully treated with rituximab

We report a case of Epstein-Barr virus infection with the subsequent development of haemophagocytic lymphohistiocytosis in a teenage Crohn's disease patient treated with azathioprine. We found that the early introduction of the anti-B cell monoclonal antibody rituximab precipitated a rapid fall in circulating B-cells and EBV viral load, resulting in a prompt and sustained recovery from what is a potentially fatal complication of azathioprine therapy in Crohn's disease patients.

Association of Crohn's disease, thiopurines, and primary epstein-barr virus infection with hemophagocytic lymphohistiocytosis

OBJECTIVE

To assess the incidence of hemophagocytic lymphohistiocytosis (HLH) in a well-defined population of children with inflammatory bowel disease (IBD) and evaluate the common clinical and laboratory characteristics of individuals with IBD who developed HLH.

STUDY DESIGN

We conducted a retrospective study of all children who developed HLH over an 8-year period. The incidence of HLH in patients with IBD was calculated using US census data and a statewide project examining the epidemiology of pediatric IBD.

RESULTS

Among children in Wisconsin, 20 cases of HLH occurred during the study period; 5 cases occurred in children with IBD. Common characteristics include: Crohn's disease (CD), thiopurine administration, fever lasting more than 5 days, lymphadenopathy, splenomegaly, anemia, lymphopenia, and elevated serum triglycerides and ferritin. Of the patients, 4 had primary Epstein-Barr virus infections. The incidence of HLH among all children in Wisconsin was 1.5 per 100 000 per year. The risk was more than 100-fold greater for children with CD (P < .00001).

CONCLUSIONS

Pediatric patients with CD are at increased risk for developing HLH; primary Epstein-Barr virus infection and thiopurine administration may be risk factors.

Thiopurine methyltransferase (TPMT) genotyping to predict myelosuppression risk

Azathioprine (AZA), 6-mercaptopurine (6-MP), and thioguanine (TG) are thiopurine drugs. These agents are indicated for the treatment of various diseases including hematologic malignancies, inflammatory bowel disease (IBD), rheumatoid arthritis, and as immunosuppressants in solid organ transplants. Thiopurine drugs are metabolized, in part, by thiopurine methyltransferase (TPMT). TPMT displays genetic polymorphism resulting in null or decreased enzyme activity. At least 20 polymorphisms have been identified, of which, TPMT *2, *3A, *3B, *3C, and *4 are the most commonly studied. These polymorphisms have been associated with increased myelosuppression risk. TPMT genotyping may be useful to predict this risk.

Cutaneous lymphoproliferative disorder complicating infectious mononucleosis in an immunosuppressed patient

Infectious mononucleosis is the syndrome produced by primary infection with Epstein-Barr virus during adolescence or early adulthood. In immunosuppressed individuals, depressed T-cell function allows the Epstein-Barr virus-driven B-cell proliferation to continue unabated, potentially leading to a lymphoproliferative disorder. A 15-year-old girl with a history of ulcerative colitis treated with 6-mercaptopurine and mesalamine presented with the acute onset of a rapidly enlarging, ulcerative nodule on her left lower eyelid 4 weeks following recovery from infectious mononucleosis. The biopsy revealed an Epstein-Barr virus-positive lymphoproliferative disorder. Systemic disease was absent. Following discontinuation of 6-mercaptopurine, the patient was treated with two courses of intravenous cyclophosphamide. The lesion resolved completely and she remains disease free at 14 months following diagnosis. We report a solitary cutaneous lesion of an immunosuppression-related lymphoproliferative disorder (IR-LPD) occurring as a complication of infectious mononucleosis, and review the pathogenesis and reported cases of Epstein-Barr virus-related immunosuppression-related lymphoproliferative disorder arising in the setting of inflammatory bowel disease. It is important for dermatologists and dermatopathologists to be aware of the occurrence of IR-LPD in patients being treated for inflammatory conditions, including inflammatory bowel disease. Given the role of primary infection with Epstein-Barr virus in the development of IR-LPD, consideration may be given to assessing Epstein-Barr virus status prior to initiating immunosuppressive therapy in young patients.

Hemophagocytic syndrome in a child with severe Crohn's disease and familial Mediterranean fever

Hemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal, severe condition of hyperinflammation caused by the uncontrolled proliferation of activated lymphocytes and histiocytes secreting high amounts of inflammatory cytokines. Here we report a fatal hemophagocytic syndrome in a 11-year-old boy with a diagnosis of both Crohn's disease receiving immunosuppressive therapy and familial Mediterranean fever. It is important to evaluate the patients with inflammatory bowel disease receiving immunosuppressive therapy presenting with unexplained fever, cytopenia, progression of organomegaly and biochemical changes for the investigation of HLH for diagnosis and treatment.

Lymphoproliferative disorders in patients receiving thiopurines for inflammatory bowel disease: a prospective observational cohort study

BACKGROUND

Reports of an increased risk of lymphoproliferative disorders in patients receiving thiopurines for inflammatory bowel disease are controversial. We assessed this risk in a prospective observational cohort study.

METHODS

19,486 patients with inflammatory bowel disease, of whom 11,759 (60.3%) had Crohn's disease and 7727 (39.7%) had ulcerative colitis or unclassified inflammatory bowel disease, were enrolled in a nationwide French cohort by 680 gastroenterologists, who reported details of immunosuppressive therapy during the observation period, cases of cancer, and deaths. The risk of lymphoproliferative disorder was assessed according to thiopurine exposure. Median follow-up was 35 months (IQR 29-40).

FINDINGS

At baseline, 5867 (30.1%) of patients were receiving, 2809 (14.4%) had discontinued, and 10,810 (55.5%) had never received thiopurines. 23 new cases of lymphoproliferative disorder were diagnosed, consisting of one case of Hodgkin's lymphoma and 22 cases of non-Hodgkin lymphoproliferative disorder. The incidence rates of lymphoproliferative disorder were 0.90 per 1000 (95% CI 0.50-1.49) patient-years in those receiving, 0.20/1000 (0.02-0.72) patient-years in those who had discontinued, and 0.26/1000 (0.10-0.57) patient-years in those who had never received thiopurines (p=0.0054). The multivariate-adjusted hazard ratio of lymphoproliferative disorder between patients receiving thiopurines and those who had never received the drugs was 5.28 (2.01-13.9, p=0.0007). Most cases associated with thiopurine exposure matched the pathological range of post-transplant disease.

INTERPRETATION

Patients receiving thiopurines for inflammatory bowel disease have an increased risk of developing lymphoproliferative disorders.

FUNDING

Programme Hospitalier de Recherche Clinique National (AOM05157), Association François Aupetit, Délégation Inter-régionale de la Recherche clinique Ile de France-Assistance Publique Hôpitaux de Paris (AP-HP), Ligue contre le Cancer, and Fonds de Recherche de la Société Nationale Française de Gastro-entérologie.

Immunizations in patients with inflammatory bowel disease

Patients receiving immunosuppressive therapies may be at increased risk for complications of vaccine preventable diseases, including influenza, varicella, and pneumococcus. However, studies suggest that patients with chronic illness may be inadequately immunized. In part, this is because of a paucity of formal vaccine studies in immune compromised populations. This review discusses the methods one uses to assess vaccine efficacy and provides an update on currently known data on the vaccine antibody responses in immune compromised hosts. Currently published studies suggest that influenza vaccine can be safely administered to patients with IBD on immunosuppression, and is effective in the majority of patients. Further formal studies with other inactivated vaccines (e.g., pneumococcal vaccine, meningitis vaccine) should be conducted. While some studies in immune compromised hosts suggest the live attenuated varicella vaccine can be given without adverse events, administration of this vaccine in patients on immunosuppression remains controversial.

Epstein-barr virus-related diarrhea or exacerbation of inflammatory bowel disease: diagnostic dilemma

While the presence of Epstein-Barr virus (EBV) in colonic specimens from patients with inflammatory bowel disease (IBD) has been documented, diarrhea secondary to gastrointestinal involvement by EBV in the context of primary EBV infection in patients with IBD has not been reported. We describe a patient with IBD who presented with diarrhea and primary EBV infection and propose a role for colonic involvement by EBV in the pathogenesis of his symptoms.

Fatal Epstein-Barr virus primo infection in a 25-year-old man treated with azathioprine for Crohn's disease

We report a case of Epstein-Barr virus (EBV) primo infection with the development of successive infectious mononucleosis, hemophagocytic lymphohistiocytosis, and B-cell lymphoproliferative disorder in a patient treated with azathioprine for Crohn's disease. This case report suggests that specific EBV-related clinical and virological management should be considered when treating a patient with inflammatory bowel disease with azathioprine.

Effectiveness of an 'half elemental diet' as maintenance therapy for Crohn's disease: A randomized-controlled trial

BACKGROUND

Although thiopurines have a proven role in maintenance therapy for Crohn's disease, an alternative therapy is needed for patients intolerant or resistant to thiopurines.

AIM

To evaluate the effectiveness of home enteral nutrition as a maintenance therapy regimen in which half of the daily calorie requirement is provided by an elemental diet and the remaining half by a free diet. We refer to this home enteral nutrition therapy as 'half elemental diet'.

METHODS

Between 2002 and 2005, 51 patients in remission from two hospitals were randomly assigned to a half elemental diet group (n = 26) or a free diet group (n = 25). The primary outcome measure of this study was the occurrence of relapse over the 2-year period.

RESULTS

The relapse rate in the half elemental diet group was significantly lower [34.6% vs. 64.0%; multivariate hazard ratio 0.40 (95% CI: 0.16-0.98)] than that in the free diet group after a mean follow-up of 11.9 months. Compliance was similar in the two groups. No adverse event occurred in any of the patients throughout the study.

CONCLUSION

This randomized-controlled trial shows the effectiveness of an half elemental diet, which is a promising maintenance therapy for Crohn's disease patients.

Reactive hemophagocytic syndrome complicating the treatment of inflammatory bowel disease

BACKGROUND AND AIMS

Reactive hemophagocytic syndrome (RHS) is a rare disease in which inappropriately activated macrophages consume bone marrow-derived cells. Most cases are associated with infection in the setting of immunodeficiency. The widespread use of immunosuppressive therapy in the treatment of inflammatory bowel disease (IBD) places patients with Crohn's disease and ulcerative colitis at risk of this complication. No concerted effort has been made to alert gastroenterologists of this condition, and treatment recommendations are lacking. The aims of this study were to describe the clinical and laboratory features of RHS associated with IBD and to review diagnostic criteria, treatment options, and pathogenesis.

MATERIALS AND METHODS

Clinical and laboratory data were pooled from the clinical practice of the investigators and from published cases. Descriptive statistics were performed.

RESULTS AND CONCLUSIONS

Seven cases of RHS complicating the treatment of IBD were identified. All patients were on immunosuppressive therapy, with nearly half taking >1 agent. All patients presented with fever, leukopenia, anemia, and hyperferritinemia. Infection by a member of the herpesvirus family or an intracellular pathogen precipitated RHS in 6 of 7 patients. The mortality rate was 29%. The diagnosis of RHS should be considered in patients with IBD taking immunosuppressive therapy who present with fever and cytopenia. Evaluation should begin with a serum ferritin. In patients with a serum ferritin > or =10,000 ng/mL, a bone marrow biopsy should be performed to confirm hemophagocytosis. If the initial evaluation is negative, then clinical suspicion should be maintained until the episode resolves.

Review article: practical management of inflammatory bowel disease patients taking immunomodulators

Azathioprine, mercaptopurine, methotrexate, ciclosporin and tacrolimus all have their respective niches in the treatment of inflammatory bowel disease. These immunomodulators are potent and effective medications; however, they potentially have serious toxicity. To maximize benefit and minimize risk, clinicians must understand the mechanism of action, appropriate indications, range of toxicity and proper dosing of these medications. Furthermore, once initiating therapy, patients need to be monitored appropriately for evidence of efficacy and toxicity. This review includes the rationale behind recommendations for the management and monitoring of patients using immunomodulators. For the purine antagonists--azathioprine and mercaptopurine--the evidence for utility of thiopurine methyltransferase testing and mercaptopurine metabolite monitoring is addressed. The roles of liver biopsy and screening for methylenetetrahydrofolate reductase mutations in patients taking methotrexate are reviewed. With appropriate monitoring, the calcineurin inhibitors--ciclosporin and tacrolimus--can be used safely and effectively. Immunomodulators are important agents for the treatment of Crohn's disease and ulcerative colitis, and prescribing clinicians should be comfortable recognizing both their value and their limitations.

Methods to avoid infections in patients with inflammatory bowel disease

Infections have been reported in patients with inflammatory bowel disease (IBD), especially in association with anti-inflammatory and immunomodulatory medications used to treat IBD. Unfortunately, there is a dearth of information on infectious complication risk in patients with IBD. This review describes infectious complications reported in patients with IBD and provides a framework for future studies to assess potential risk factors and incidence for infection. Recommendations are also provided for prevention of infection.