The Impact of Azathioprine-Associated Lymphopenia on the Onset of Opportunistic Infections in Patients with Inflammatory Bowel Disease

Precision medicine in monogenic inflammatory bowel disease: proposed mIBD REPORT standards

Owing to advances in genomics that enable differentiation of molecular aetiologies, patients with monogenic inflammatory bowel disease (mIBD) potentially have access to genotype-guided precision medicine. In this Expert Recommendation, we review the therapeutic research landscape of mIBD, the reported response to therapies, the medication-related risks and systematic bias in reporting. The mIBD field is characterized by the absence of randomized controlled trials and is dominated by retrospective observational data based on case series and case reports. More than 25 off-label therapeutics (including small-molecule inhibitors and biologics) as well as cellular therapies (including haematopoietic stem cell transplantation and gene therapy) have been reported. Heterogeneous reporting of outcomes impedes the generation of robust therapeutic evidence as the basis for clinical decision making in mIBD. We discuss therapeutic goals in mIBD and recommend standardized reporting (mIBD REPORT (monogenic Inflammatory Bowel Disease Report Extended Phenotype and Outcome of Treatments) standards) to stratify patients according to a genetic diagnosis and phenotype, to assess treatment effects and to record safety signals. Implementation of these pragmatic standards should help clinicians to assess the therapy responses of individual patients in clinical practice and improve comparability between observational retrospective studies and controlled prospective trials, supporting future meta-analysis.

Purine antimetabolites associated Pneumocystis jirovecii pneumonia

PURPOSE

To detect the possible safety signal of purine antimetabolites associated with Pneumocystis jirovecii pneumonia through disproportionality analysis in the FDA Adverse Event Reporting System (FAERS) Database.

METHODS

A case/non-case retrospective disproportionality analysis was performed in the publicly available FAERS database using AERSmine (2004Q1-2021Q3). Four models were developed to explore the signal strength of PAs among different populations with possible confounding factors. Reporting odds ratio (ROR) and Proportional reporting ratio (PRR) was used as the data mining algorithm for the analysis. A value of ROR-1.96SE > 1 and PRR ≥ 2 with an associated X2 value of 4 or more was considered the threshold for a signal.

RESULTS

A total of 7073 reports associated with Pneumocystis jirovecii pneumonia were present in the database, of which 899 reports were associated with purine antimetabolites. A crude signal strength of ROR 15.76(14.70-16.91) was obtained for purine antimetabolites associated PJP, with the highest signal strength reported with fludarabine and thioguanine [ROR 19.63(17.42-22.13); 19.45(13.21-28.63)]. Stratifying the cases based on autoimmune disorders and the cancer population revealed an ROR of 3.33(2.46-4.50) and 2.93(2.26-3.79) respectively. The highest risk of PJP with use of PAs was observed amongst children with a higher risk of nearly 2 times than the adult population [ROR 11.57(9.16-14.62)].

CONCLUSIONS

Our study provided evidence on the occurrence of PJP with the use of purine antimetabolites among the autoimmune and cancer population. We identified signals for PJP with azathioprine, mercaptopurine, thioguanine, cladribine, fludarabine, and clofarabine. More research with a superior epidemiological study design of a defined population is required to validate these findings.

Identification of Covariates Modulating B-Cell Repopulation Kinetics in Subjects Receiving Rituximab Treatment

OBJECTIVE

B-cell depletion using the anti-CD20 monoclonal antibody rituximab is a cornerstone in the therapeutic concept of multiple autoimmune diseases. B-cell depletion is associated with a higher risk for severe infections, and the time span of B-cell repopulation differs greatly between individuals. Data on factors influencing B-cell repopulation kinetics are limited. This study aims to identify patient-specific and therapy-associated covariates that modulate B-cell repopulation.

METHODS

This single-center retrospective observational study presents data of 839 subjects receiving 2,017 courses of rituximab for autoimmune diseases. Assessed covariates are patient-specific factors (sex, age, kidney function, and underlying disease) and co-immunosuppression with common agents (azathioprine, cyclosporine A, cyclophosphamide, hydroxychloroquine, methotrexate, mycophenolate mofetil, tacrolimus, and corticosteroids). The primary end point is the time to B-cell repopulation (≥5/μl). The secondary end point is the time to B-cell reconstitution (≥50/μl). Multivariate time-to-event analysis and logistic regression models were applied to estimate the influence of covariates.

RESULTS

Age over 60 years (hazard ratio [HR] 0.71 for repopulation, P = 0.008), impaired kidney function (HR 0.72, P = 0.001), antineutrophil cytoplasmic antibody-associated vasculitis (HR 0.61, P < 0.001), solid organ transplantation (HR 0.4, P < 0.001), and co-immunosuppression with corticosteroids (HR 0.64, P < 0.001) or azathioprine (HR 0.49, P < 0.001) were associated with impaired B-cell repopulation and reconstitution. Effects of corticosteroids (P = 0.043) and azathioprine (P = 0.025) were dose dependent.

CONCLUSION

Prolonged rituximab dosing intervals may be effective to achieve B-cell depletion and reduce risk of infection in advanced age or patients with impaired kidney function. Co-medication with corticosteroids or azathioprine prolongs B-cell recovery, which may increase therapeutic effects but also the rate of adverse events.

Cytomegalovirus Pneumonia in Inflammatory Bowel Disease: Literature Review and Clinical Recommendations

Aim

The objective was to elucidate the correlation between CMVP and immunosuppressive therapy in IBD patients, we hope this review could expand on the significance of CMV as an opportunistic pathogen and the potential impact on morbidity and mortality in IBD patients.

Methods

Records and clinical trajectories linked to CMVP in IBD patients were extracted from the PubMed database, irrespective of language barriers. The reference lists incorporated in these studies were manually inspected. Conclusions were generated using straightforward descriptive analysis.

Results

In total, 18 IBD patients, including Crohn's disease (CD, 67%) and Ulcerative Colitis (UC, 33%), affected by CMVP were identified from 17 published articles. A minority of these patients (17%) exhibited active disease, whereas the majority (83%) presented with quiescent disease. Fever (100%) and dyspnea (44%) emerged as the most prevalent clinical symptoms. All the patients had undergone immunosuppressive therapy. A significant proportion, up to 89%, had received thiopurine treatment prior to the CMVP diagnosis. Interestingly, none of the patients were subjected to biological therapy. Half of the patients manifested with Hemophagocytic Lymphohistiocytosis (HLH). Almost all patients (94%) were administered antiviral treatment and a substantial 83% experienced full recovery. Immunosuppressive agents were either tapered or discontinued altogether. A subset of patients, 17%, suffered fatal outcomes.

Conclusion

Our findings underscore the need for heightened suspicion of CMVP in IBD patients who exhibit symptoms such as fever and dyspnea. During the COVID-19 pandemic, CMVP should be considered a potential differential diagnosis. It was observed that CMVP primarily transpires during CD remission. Azathioprine emerged as the predominant immunosuppressant linked to CMV reactivation. The prompt application of effective antiviral therapy can substantially enhance patient outcomes. CMV vaccine might serve as a viable prevention strategy.

Evaluation of the mTORC activity in the presence of Toxoplasma gondii and azathioprine in human monocyte cell line

BACKGROUND

Autophagy is an important part of pathogenesis of IBD. Thiopurines such as azathioprine (AZA) are approved drugs for clinical practices in IBD patients. Besides, as an escape strategy, Toxoplasma gondii can use the mTORC1 complex to inactivate autophagy.

METHODS

In this study, we investigated whether T. gondii tachyzoites may modulate autophagy and interfere the effects of azathioprine in IBD treatment. PMA-activated human monocyte cell line (THP-1) was infected with fresh T. gondii RH tachyzoites. After 5 h of infection, the cells were treated with AZA for 6 h. The expression of atg5, atg7, atg12, lc3b, and β-actin (BACT) genes was evaluated using quantitative real-time PCR. To analyze the phosphorylation of ribosomal protein S6 (rpS6), western blot using specific primary antibodies was performed.

RESULTS

The results of real-time PCR revealed that AZA, T. gondii tachyzoites, and a combination of AZA and T. gondii tachyzoites upregulated atg5 gene for 4.297-fold (P-value = 0.014), 2.49-fold (P-value = 0.006), and 4.76-fold (P-value = 0.001), respectively. The atg7 gene showed significant upregulation (2.272-fold; P-value = 0.014) and (1.51-fold; P-value = 0.020) in AZA and AZA / T. gondii, respectively. The expression of atg12 gene was significantly downregulated in AZA and T. gondii tachyzoites for (8.85-fold; P-value = 0.004) and (2.005-fold; P-value = 0.038), respectively, but upregulated in T. gondii/AZA (1.52-fold; P-value = 0.037). In addition, the lc3b gene was only significantly changed in AZA / T. gondii (3.028-fold; P-value = 0.001). Western blot analysis showed that T. gondii tachyzoites significantly phosphorylated rpS6, and tachyzoites did not interfere the effects of AZA to phosphorylate the rpS6.

CONCLUSION

Taken together, although AZA and T. gondii similarly affects the expression levels of atg5, atg7, and atg12, but T. gondii does not seem to modulate the effects of AZA via mTORC functions.

Azathioprine therapy induces selective NK cell depletion and IFN-γ deficiency predisposing to herpesvirus reactivation

BACKGROUND

Azathioprine is a widely prescribed drug for patients with chronic inflammatory diseases such as myasthenia gravis or organ transplant recipients. Azathioprine exerts immunosuppressive effects by inhibiting intracellular purine synthesis and reducing the numbers of circulating B and T lymphocytes. Case reports indicate increased risk for serious infections that can occur despite regular measurements of lymphocyte counts during azathioprine therapy.

OBJECTIVE

We sought to comprehensively investigate therapy-associated patient risks and the underlying immune dysfunction of azathioprine use.

METHODS

Peripheral blood leukocytes were analyzed using single-cell mass and spectral flow cytometry to detect specific effects of azathioprine use on the systemic immune signature. Therapy-associated clinical features were analyzed in 2 independent cohorts of myasthenia gravis patients.

RESULTS

Azathioprine therapy selectively induced pronounced CD56^dimCD16⁺ natural killer cell depletion and concomitant IFN-γ deficiency. Cytokine profiling revealed a specific contraction of classical T_H1 cells during azathioprine treatment. We further observed an increased occurrence of reactivation of endogenous latent herpesviruses in the azathioprine-treated group versus in patients with myasthenia gravis who were not receiving immunomodulatory treatment; this increased occurrence was validated in an independent cohort.

CONCLUSION

Our study highlights the risk of development of adverse events during azathioprine therapy and suggests that natural killer cell monitoring could be valuable in clinical practice.

The complex relationship between viruses and inflammatory bowel disease - review and practical advices for the daily clinical decision-making during the SARS-CoV-2 pandemic

The coronavirus disease 2019 (COVID-19) outbreak emerged in December 2019 in China and rapidly spread worldwide. Inflammatory bowel disease (IBD) patients are likely to be more susceptible to viral infections, and this is significantly influenced by the type of therapy they receive. Thus, issues specifically concerning the medical treatment of IBD patients were shortly addressed at the beginning of the pandemic. However, recently available data on the occurrence and outcome of SARS-CoV-2 infection in IBD patients does not address the concerns raised at the beginning of the pandemic. Growing evidence and the rapid changes happening over the past few weeks have helped elucidate the current situation, contribute to our understanding of the disease, and many previously raised questions could now be answered. We hereby summarise available evidence regarding viral infections and IBD, focusing on SARS-CoV infections, and we provide practical recommendations related to patient management during the COVID-19 pandemic era.

Risk of common infections in people with inflammatory bowel disease in primary care: a population-based cohort study

OBJECTIVE

To evaluate the risk of common infections in individuals with inflammatory bowel disease (IBD) [ulcerative colitis and Crohn's disease] compared with matched controls in a contemporary UK primary care population.

DESIGN

Matched cohort analysis (2014-2019) using the Royal College of General Practitioners Research and Surveillance Centre primary care database. Risk of common infections, viral infections and gastrointestinal infections (including a subset of culture-confirmed infections), and predictors of common infections, were evaluated using multivariable Cox proportional hazards models.

RESULTS

18 829 people with IBD were matched to 73 316 controls. People with IBD were more likely to present to primary care with a common infection over the study period (46% vs 37% of controls). Risks of common infections, viral infections and gastrointestinal infections (including stool culture-confirmed infections) were increased for people with ulcerative colitis and Crohn's disease compared with matched controls (HR range 1.12-1.83, all p<0.001). Treatment with oral glucocorticoid therapy, immunotherapies and biologic therapy, but not with aminosalicylates, was associated with increased infection risk in people with IBD. Despite mild lymphopenia and neutropenia being more common in people with IBD (18.4% and 1.9%, respectively) than in controls (6.5% and 1.5%, respectively), these factors were not associated with significantly increased infection risk in people with IBD.

CONCLUSION

People with IBD are more likely to present with a wide range of common infections. Health professionals and people with IBD should remain vigilant for infections, particularly when using systemic corticosteroids, immunotherapies or biologic agents.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov (NCT03835780).

Lymphopenia and intratumoral lymphocytic balance in the era of cancer immuno-radiotherapy

INTRODUCTION

The immune response has been recognized as a major tumor-eradication component of radiotherapy.

OBJECTIVE

This review studies, under a clinical perspective, two contrasting effects of radiotherapy, namely immunosuppression and radiovaccination.

MATERIALS AND METHODS

We critically reviewed the available clinical and experimental experience on radiotherapy-induced lymphopenia.

RESULTS

Radiation-induced tumor damage promotes radio-vaccination, enhances cytotoxic immune responses, and potentiates immunotherapy. Nevertheless, radiotherapy induces systemic and intratumoral lymphopenia. The above effects are directly related to radiotherapy fractionation and field size/location, and tumor characteristics.

DISCUSSION

Hypofractionated stereotactic and accelerated irradiation better promotes radio-vaccination and produces less severe lymphopenia. Adopting cytoprotective policies and combining lympho-stimulatory agents or agents blocking regulatory lymphocyte activity are awaited to unmask the radio-vaccination effect, enhancing the efficacy immuno-radiotherapy.

CONCLUSION

Radiation-induced lymphopenia and immunosuppression are important issues that should be considered in the design of immuno-radiotherapy clinical trials.

Common infections, mental health problems and healthcare use in people with inflammatory bowel disease: a cohort study protocol

Introduction

People with inflammatory bowel disease (IBD) are at increased risk of pneumonia and herpes zoster, yet other common infection types have not been explored. Anxiety and depression are more prevalent in IBD; however, the impact of these conditions on primary care healthcare use in IBD is not known.

Methods and analysis

We will perform two retrospective studies using a large English population-based primary care cohort to compare the following outcomes in people with IBD and matched controls: incident infections (Study 1) and prevalent mental health problems and healthcare use, overall and in those with and without mental health problems (Study 2). All adults registered with general practices contributing to Royal College of General Practitioners Research and Surveillance Centre database between 1 January 2014 and 1 January 2019 are eligible. Infection outcomes comprise the incidence of common infections (upper respiratory tract infections, pneumonia, acute bronchitis, influenza and influenza-like illnesses, skin infections, herpes simplex and herpes zoster infections, genital infections, urinary tract infections and gastrointestinal infections) and any viral infection. Mental health and healthcare use outcomes are: prevalence of depressive episodes; anxiety episodes; recurrent depression; rates of primary care and emergency secondary care visits; primary-care issued sick notes (reflecting time off work). Analyses will be adjusted for sociodemographic factors recorded in the primary care record.

Discussion

These studies will quantify the infection risk in IBD, the excess burden of anxiety and depression in a population-based IBD cohort, and the impact of mental health conditions on healthcare use and time off work. Greater understanding and awareness of infection risk and common mental health issues will benefit people with IBD and healthcare practitioners and will guide policy makers as allocation of resource may be guided by the real-world information produced by these studies.

Trial registration number

NCT03836612.

Coronavirus Disease 2019 in Autoimmune Hepatitis: A Lesson From Immunosuppressed Patients

Chronic immunosuppression is associated with increased and more severe viral infections. However, little is known about the association between immunosuppression and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Our aim was to describe the clinical course of patients with immunosuppressed autoimmune hepatitis (AIH) during coronavirus disease 2019 (COVID-19) infection in Italy. Our study is a case series of patients with AIH treated with immunosuppression, who tested positive for SARS-CoV-2 in March 2020 during the outbreak of COVID-19. Ten patients from seven different hospitals in Italy were diagnosed with COVID-19 during the outbreak of SARS-CoV-2 in March 2020. Seven subjects were female (70%), and age ranged from 27 to 73 years. Before the onset of SARS-CoV-2 infection, all patients were taking immunosuppressive therapy for AIH, and eight of them were on biochemical remission. Two other patients had recent acute onset of their AIH, and consequently started high-dose steroids, as per induction protocol. All patients had a respiratory syndrome and a positive nasal swab for SARS-CoV-2. Five patients developed a computed tomography-confirmed COVID-19 pneumonia. Six subjects received a combination of antiretroviral and antimalarial drugs. In seven patients, the dosage of immunosuppressive medication was changed. Liver enzymes were repeated during SARS-CoV-2 infection in all hospitalized cases; they remained within the normal range in all cases, and improved in the two acute cases treated with high-dose steroids. The clinical outcome was comparable to the reported cases occurring in non-immunosuppressed subjects. Conclusion: Patients under immunosuppressive therapy for AIH developing COVID-19 show a disease course presumptively similar to that reported in the non-immunosuppressed population. These data might aid in medical decisions when dealing with SARS-CoV-2 infection in immunocompromised patients.

Immunotherapy for ANCA-associated vasculitis during the COVID-19 pandemic

Since the first description of infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China in December 2019, it has evolved into a pandemic and emerged as an unprecedented worldwide crisis overwhelming healthcare systems globally. Analysis of the available literature to date suggests that, in addition to older age, patients with underlying co-morbidities including hypertension, diabetes, heart disease are at higher risk for severe disease with increased mortality. Practitioners around the world also have become increasingly concerned that immunosuppressed patients including those with autoimmune diseases may be at increased risk for developing Coronavirus Disease 2019 (COVID-19) with serious complications. Very little is known about how anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis modifies the susceptibility, clinical presentation and disease course of COVID-19. In this review, we discuss the mechanism of action and challenges of the current therapeutic armamentarium of ANCA-associated vasculitis and outline approaches to management of ANCA-associated vasculitis during the COVID-19 pandemic.

Immunosuppressive agents for dermatological indications in the ongoing COVID-19 pandemic: Rationalizing use and clinical applicability

The ongoing COVID-19 epidemic has brought to the fore many concerns related to use of immunosuppressive agents (ISAs) in dermatology. While it is unclear whether the patients on ISAs for skin conditions are more prone to develop COVID-19, and what impact the ISA may have on the clinical outcome if a patient does get infected, rationalizations based on the specific immune effects of each drug, and existing literature on incidence of various infections with each, are possible. In this review, we provide the readers with practically useful insights into these aspects, related to the conventional ISAs, and briefly mention the clinical outcome data available on related scenarios from other patient groups so far. In the end, we have attempted to provide some clinically useful points regarding practical use of each dermatologically relevant conventional ISA in the current scenario.

Consensus Statement On Immune Modulation in Multiple Sclerosis and Related Disorders During the COVID-19 Pandemic: Expert Group on Behalf of the Indian Academy of Neurology

Knowledge related to SARS-CoV-2 or 2019 novel coronavirus (2019-nCoV) is still emerging and rapidly evolving. We know little about the effects of this novel coronavirus on various body systems and its behaviour among patients with underlying neurological conditions, especially those on immunomodulatory medications. The aim of the present consensus expert opinion document is to appraise the potential concerns when managing our patients with underlying CNS autoimmune demyelinating disorders during the current COVID-19 pandemic.

Clinical assessment of risk factors for infection in inflammatory bowel disease patients

PURPOSE

Recognizing patients with inflammatory bowel disease who are prone to infection would enable the adjustment of the type and intensity of immunosuppressive treatment. The aim of this study was to identify a clinical profile of risk for infections in IBD patients, based on the interaction of immunosuppressive treatment with factors inherent to the patient.

METHODS

A case-control study was performed among patients older than 18 years. Patients with any significant infection (any kind of severe or recurrent infection according to standard clinical criteria or a critical enough infection according to the patient) were defined as cases. Both cases and controls were randomly selected in a 1:3 ratio. All the period from diagnosis to the end of recruitment (June 2016) was analyzed. Risk factors for infection were identified by logistic regression analysis; the strength of association was reported by odds ratio (OR) with 95% confidence interval (95%CI).

RESULTS

A total of 112 cases and 270 controls were included. The independent risk factors for significant infection are the number of immunosuppressants (one drug: OR 1.28, 95% CI 0.53-3.11, two drugs: OR 2.37, 95% CI 1.01-5,56, and three drugs: OR 5.84, 95% CI 1.57-21.72), body mass index (OR 1.08; 95 %CI 1,01-1,16), the degree of comorbidity (OR 1.52; 95% CI 1.04-2.21), and the intensity of inflammatory activity (OR 1.43; 95% CI 1.19-1.71).

CONCLUSIONS

Regardless of immunosuppression, several patient factors such as comorbidity, body mass index, or the inflammatory activity of the disease determine the individual risk of infectious complications and should be considered for an adequate risk assessment.

Comparative Risk of Serious Infections With Biologic and/or Immunosuppressive Therapy in Patients With Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

We performed a systematic review and meta-analysis to evaluate the comparative risk of serious infections with tumor necrosis factor (TNF) antagonists, non-TNF targeted biologics, tofacitinib, and immunosuppressive agents in patients with inflammatory bowel diseases (IBDs).

METHODS

In a systematic search of publications, through March 18, 2018, we identified 15 observational studies (>500 person-years) of patients with IBD treated with TNF antagonists, non-TNF targeted biologics, tofacitinib, and/or immunosuppressive agents (thiopurines, methotrexate) that reported risk of serious infections. Only studies with active comparators were included, to allow appropriate comparative synthesis. We performed random-effects meta-analysis and estimated relative risk (RR) and 95% CIs.

RESULTS

Compared with anti-TNF monotherapy, risk of serious infection increased with the combination of anti-TNF and an immunosuppressive agent (in 6 cohorts: RR, 1.19; 95% CI, 1.03-1.37), with anti-TNF and a corticosteroid (in 4 cohorts: RR, 1.64; 95% CI, 1.33-2.03), or with all 3 drugs (in 2 cohorts: RR, 1.35; 95% CI, 1.04-1.77); there was minimal heterogeneity among studies. In contrast, monotherapy with an immunosuppressive agent was associated with a lower risk of serious infections than monotherapy with a TNF antagonist (7 cohorts: RR, 0.61; 95% CI 0.44-0.84) or a TNF antagonist with an immunosuppressive agent (2 cohorts: RR, 0.56; 95% CI, 0.39-0.81). Infliximab-based therapy was associated with a lower risk of serious infections compared with adalimumab-based therapy in patients with ulcerative colitis (4 cohorts: RR, 0.57; 95% CI, 0.33-0.97), but not Crohn's disease (4 cohorts: RR, 0.91; 95% CI, 0.49-1.70). Few data were available on the comparative safety of biologic agents that do not inhibit TNF and tofacitinib.

CONCLUSIONS

Combination therapies for IBD that include TNF antagonists, especially with corticosteroids, are associated with a higher risk of serious infection, whereas monotherapy with an immunosuppressive agent is associated with a lower risk, compared with monotherapy with a TNF antagonist. Studies are needed to evaluate the comparative safety of non-TNF targeted biologics and small molecules for treatment of IBD.

The Evolving Role of Thiopurines in Inflammatory Bowel Disease

PURPOSE OF REVIEW

With the advent of biologic therapies for the treatment of inflammatory bowel disease, the roles of thiopurines have continued to evolve. This review will focus on recent advances in pharmacology and the safety and efficacy of thiopurines as maintenance therapies for steroid-induced remissions and post-surgical maintenance of remission and as combination therapies to reduce immunogenicities of biologic agents.

RECENT FINDINGS

Due to pharmacogenetics of thiopurine S-methyltransferase, thiopurine dosing is more effectively based on monitoring of thiopurine metabolites rather than weight-based dosing. Thiopurines continue to have a role as maintenance therapy after steroid-induced remissions and in combination with biologics to induce and maintain remission. Safety monitoring includes measurements of blood counts, liver chemistries, and dermatologic evaluations and protection from sun exposure. Thiopurines appear to be safe during pregnancies and while very uncommon, lymphomas (including hepatosplenic T cell lymphomas) remain a recognized risk, particularly in younger and older males.

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.

BAFF-driven B cell hyperplasia underlies lung disease in common variable immunodeficiency

BACKGROUND

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency and is frequently complicated by interstitial lung disease (ILD) for which etiology is unknown and therapy inadequate.

METHODS

Medical record review implicated B cell dysregulation in CVID ILD progression. This was further studied in blood and lung samples using culture, cytometry, ELISA, and histology. Eleven CVID ILD patients were treated with rituximab and followed for 18 months.

RESULTS

Serum IgM increased in conjunction with ILD progression, a finding that reflected the extent of IgM production within B cell follicles in lung parenchyma. Targeting these pulmonary B cell follicles with rituximab ameliorated CVID ILD, but disease recurred in association with IgM elevation. Searching for a stimulus of this pulmonary B cell hyperplasia, we found B cell-activating factor (BAFF) increased in blood and lungs of progressive and post-rituximab CVID ILD patients and detected elevation of BAFF-producing monocytes in progressive ILD. This elevated BAFF interacts with naive B cells, as they are the predominant subset in progressive CVID ILD, expressing BAFF receptor (BAFF-R) within pulmonary B cell follicles and blood to promote Bcl-2 expression. Antiapoptotic Bcl-2 was linked with exclusion of apoptosis from B cell follicles in CVID ILD and increased survival of naive CVID B cells cultured with BAFF.

CONCLUSION

CVID ILD is driven by pulmonary B cell hyperplasia that is reflected by serum IgM elevation, ameliorated by rituximab, and bolstered by elevated BAFF-mediated apoptosis resistance via BAFF-R.

FUNDING

NIH, Primary Immune Deficiency Treatment Consortium, and Rare Disease Foundation.

Efforts in redesigning the antileukemic drug 6-thiopurine: decreasing toxic side effects while maintaining efficacy

6-Thiopurine (6TP) is a currently prescribed drug in the treatment of diseases ranging from Crohn's disease to acute lymphocytic leukemia. While its potent mode of action is through incorporation into DNA as a thiol mimic of deoxyguanosine, severe toxicities are associated with its administration which hinder the potential therapeutic application. We have previously reported in vitro that the oxidative metabolites of 6TP, specifically 6-thiouric acid (6TU, K _i 7 μM), are potent inhibitors of UDP-glucose dehydrogenase (UDPGDH), an enzyme that is responsible for the formation of UDP-glucuronic acid (UDPGA), an essential substrate that is used in detoxification processes in the liver. An in vivo investigation was undertaken to probe if 6TU inhibits UDPGDH in rat hepatocytes, and it was observed that 6TU does greatly suppress the conjugation of bilirubin with UDPGA. The failed excretion of bilirubin is linked to a majority of the reported toxicities associated with 6TP administration. Efforts were undertaken for the construction of 6TP analogs, substituted at the C8 position, to reduce inhibition of UDPGDH while retaining therapeutic efficacy. Three new 6TP analogs bearing a halogen (Br, Cl, and F) at the C8 position have been achieved over five-synthetic steps in overall yields of 16 to 32%. Each of these analogs were shown to have reduced inhibition towards UDPGDH, with K _i values of 192, 163, 215 μM, respectively. In addition, the bromine, chlorine, and fluorine analogs were shown to possess cytotoxicity towards the REH cell line (acute lymphocytic leukemia) having IC₅₀ values of 9.54 μM (±0.97), 3.95 μM (±1.94), and 4.71 μM (±1.40), respectively. These three new 6TP analogs represent the first steps in the redesign of this potent anticancer agent into a better drug that possesses reduced toxic side effects while retaining therapeutic potency.

Fungal infections in patients with inflammatory bowel disease: A systematic review

BACKGROUND

Despite reports of fungal infections in patients with inflammatory bowel disease (IBD), their clinical and microbiological characteristics remain unknown.

OBJECTIVES

The aim of this systematic review was to examine all available evidence regarding fungal infections in patients with IBD.

METHODS

Systematic search of PubMed (through 27 May 2017) for studies providing data on clinical, microbiological, treatment and outcome data of fungal infections in patients with IBD. The primary study outcome was to record the most common fungal species in patients with IBD. Secondary outcomes were classified into 3 categories: (i) characteristics of fungal infections; (ii) data on IBD and (iii) treatment and outcomes of fungal infections in patients with IBD.

RESULTS

Fourteen studies with data on 1524 patients were included in final analysis. The most common fungal infections in patients with IBD were caused by Candida species (903 infections); the most commonly reported site of Candida infection was the gastrointestinal tract. Available evidence shows that most fungal infections occur within 12 months of IBD treatment and within 6 months when anti-TNFa agents are used.

CONCLUSIONS

This systematic review thoroughly describes fungal infections in patients with IBD and provides important information for the early detection and management of these infections.

Lymphopenia in atopic dermatitis patients treated with oral immunosuppressive drugs

INTRODUCTION

Oral immunosuppressive drugs are commonly used in the treatment of atopic dermatitis (AD). In patients with autoimmune- and rheumatic diseases, these drugs have been associated with lymphopenia. Lymphopenia is related to an increased risk of opportunistic infections. The incidence of lymphopenia in patients with AD treated with oral immunosuppressive drugs is yet unknown.

OBJECTIVE

To evaluate the occurrence of recurrent lymphopenia in patients with AD treated with oral immunosuppressive drugs and to make recommendations for screening in daily practice.

METHODS

Patients with recurrent lymphopenia (i.e. >5 times lymphocyte counts below 0.8 × 10⁹/L) during treatment with oral immunosuppressive drugs were included from our immunosuppressive drugs database and further analyzed.

RESULTS

A total of 360 AD patients, treated with oral immunosuppressive drugs, were screened. A recurrent lymphopenia during treatment was found in 11 patients. In 8/11 patients, recurrent lymphopenia was observed during concomitant treatment with prednisone. No serious infections were observed.

CONCLUSION

Lymphopenia is occasionally seen in AD patients treat with oral immunosuppressive drugs. Concomitant treatment with prednisone seems to be a risk factor. We suggest to include monitoring of lymphocyte counts in the standard follow-up for all AD patients treated with oral immunosuppressive drugs.

[Severe lymphopenia in a patient with Crohn's disease]

We report on a 25-year-old female patient with Crohn's disease and profound lymphocytopenia while receiving corticosteroids and azathioprine. Discontinuation of azathioprine only resulted in a mild increase in CD4⁺ T cell numbers; however, therapy with the TNFα inhibitor adalimumab was initiated for a clinical flare and resulted in long-lasting clinical remission and rapid normalization of the lymphocytopenia including the respective lymphocyte subsets. Lymphocytopenia is frequently observed as a side effect of immunosuppressive therapy. This case illustrates that lymphocytopenia may also occur in relation to Crohn's disease activity as an extraintestinal manifestation and may then be efficiently treated by escalation of immunosuppressive therapy.

A practical guide to thiopurine prescribing and monitoring in IBD

Thiopurines are often the mainstay of treatment for many patients with inflammatory bowel disease. As such, a general understanding of the evidence behind their use and of their metabolism is extremely useful in clinical practice. This review gives a practical overview of thiopurine metabolism, the importance of thiopurine S-methyltransferase testing prior to the start of therapy and the monitoring of thioguanine nucleotide levels while on treatment, guiding a personalised approach to optimising thiopurine therapy.

Inhibition of UDP-glucose dehydrogenase by 6-thiopurine and its oxidative metabolites: Possible mechanism for its interaction within the bilirubin excretion pathway and 6TP associated liver toxicity

6-Thiopurine (6TP) is an actively prescribed drug in the treatment of various diseases ranging from Crohn's disease and other inflammatory diseases to acute lymphocytic leukemia and non-Hodgkin's leukemia. While 6TP has beneficial therapeutic uses, severe toxicities are also reported with its use, such as jaundice and liver toxicity. While numerous investigations into the mode in which toxicity originates has been undertaken. None have investigated the effects of inhibition towards UDP-Glucose Dehydrogenase (UDPGDH), an oxidative enzyme responsible for UDP-glucuronic acid (UDPGA) formation or UDP-Glucuronosyl transferase (UGT1A1), which is responsible for the conjugation of bilirubin with UDPGA for excretion. Failure to excrete bilirubin leads to jaundice and liver toxicity. We proposed that either 6TP or its primary oxidative excretion metabolites inhibit one or both of these enzymes, resulting in the observed toxicity from 6TP administration. Inhibition analysis of these purines revealed that 6-thiopurine has weak to no inhibition towards UDPGDH with a K_i of 288 μM with regard to varying UDP-glucose, but 6-thiouric (primary end metabolite, fully oxidized at carbon 2 and 8, and highly retained by the body) has a near six-fold increased inhibition towards UDPGDH with a K_i of 7 μM. Inhibition was also observed by 6-thioxanthine (oxidized at carbon 2) and 8-OH-6TP with K_i values of 54 and 14 μM, respectively. Neither 6-thiopurine or its excretion metabolites were shown to inhibit UGT1A1. Our results show that the C2 and C8 positions of 6TP are pivotal in said inhibition towards UDPGDH and have no effect upon UGT1A1, and that blocking C8 could lead to new analogs with reduced, if not eliminated jaundice and liver toxicities.

B cell repopulation kinetics after rituximab treatment in ANCA-associated vasculitides compared to rheumatoid arthritis, and connective tissue diseases: a longitudinal observational study on 120 patients

Background

B cell depletion with rituximab (RTX) is approved for treatment of rheumatoid arthritis (RA) and ANCA-associated vasculitides (AAV). Recently, RTX has been shown to be effective in AAV maintenance therapy, but an optimal RTX treatment schedule is unknown and the time to B cell repopulation after RTX has not been studied.

Methods

Retrospective single-center analysis of B cell repopulation in patients with AAV, RA or connective tissue disease (CTD) treated with RTX.

Results

Beginning B cell repopulation within the first year after RTX treatment was observed in 93% of RA and 88% of CTD patients. Only 10% of patients with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) and no patient with eosinophilic granulomatosis with polyangiitis (EGPA) showed B cell repopulation within this time. Median time of B cell depletion was 26 months in GPA/MPA, and 21 months in EGPA compared to 9 months in RA, and 8 months in CTD (p < 0.0001). In 25 AAV-patients B cell depletion lasted for at least 44 months. There was a significant decline in serum immunoglobulin concentrations in GPA/MPA patients, but not in patients with RA or CTD. Significantly more GPA/MPA patients developed hygogammaglobulinemia (IgG <7 g/L) compared to patients with RA or CTD.

Conclusions

In contrast to RA and CTD, in AAV RTX induces long-lasting depletion of B cells that is associated with decreased antibody production. This observation points toward potential defects in the B cell compartment in AAV that are unmasked by immunosuppressive treatment and has important implications for the design of maintenance treatment schedules using RTX.

Safety of treatments for inflammatory bowel disease: Clinical practice guidelines of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD)

Inflammatory bowel diseases are chronic conditions of unknown etiology, showing a growing incidence and prevalence in several countries, including Italy. Although the etiology of Crohn's disease and ulcerative colitis is unknown, due to the current knowledge regarding their pathogenesis, effective treatment strategies have been developed. Several guidelines are available regarding the efficacy and safety of available drug treatments for inflammatory bowel diseases. Nevertheless, national guidelines provide additional information adapted to local feasibility, costs and legal issues related to the use of the same drugs. These observations prompted the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) to establish Italian guidelines on the safety of currently available treatments for Crohn's disease and ulcerative colitis. These guidelines discuss the use of aminosalicylates, systemic and low bioavailability corticosteroids, antibiotics (metronidazole, ciprofloxacin, rifaximin), thiopurines, methotrexate, cyclosporine A, TNFα antagonists, vedolizumab, and combination therapies. These guidelines are based on current knowledge derived from evidence-based medicine coupled with clinical experience of a national working group.