A presentation of ulcerative colitis after rituximab therapy in a patient with multiple sclerosis and literature review

Successful Treatment of Rituximab-Induced Crohn's Disease With Ustekinumab

Autoimmune optic papillitis is a rare disorder that causes progressive visual loss, often treated with rituximab (RTX). However, its use is not without risks. Here, we present a 51-year-old man who experienced vision loss because of autoimmune optic papillitis, which was well-controlled with RTX. Four years later, the patient developed abdominal pain and diarrhea and was found to have RTX-induced Crohn's disease (CD). The patient failed treatment with azathioprine, but was subsequently able to achieve clinical and endoscopic remission of his CD with ustekinumab, while continuing RTX therapy for autoimmune optic papillitis. This case report describes the efficacy of the anti-interleukin 12/23 monoclonal antibody in inducing remission of RTX-induced CD.

Role of B Cells in Relapsing-Remitting and Progressive Multiple Sclerosis and Long-Term Effects of B Cell Depletion

Depletion of circulating B lymphocytes using anti-CD20 monoclonal antibodies (mAbs) greatly reduces inflammatory activity in relapsing multiple sclerosis (RMS); it reduces progression to a lesser extent in nonrelapsing progressive MS. Mechanisms whereby anti-CD20 mAbs reduce MRI and clinical relapse activity in people with RMS are still being elucidated. Anti-CD20 agents do not fully protect from nonrelapsing disease progression, possibly due to their inability to cross the blood-brain barrier and inability to ameliorate the full extent of biology of MS progression. Anti-CD20 mAbs have a relatively favorable safety profile, at least in the short-term. Long-term safety studies are still needed.

Cytokine Release Syndrome-Associated Colitis: Insights From a Case of Rituximab-Induced Pancolitis

Rituximab (RTX), a widely used monoclonal antibody for hematologic malignancies and rheumatologic disorders, is known for infusion-related reactions. However, its potential to induce colitis is often overlooked. We present an 85-year-old woman with chronic lymphocytic leukemia experiencing severe adverse effects during her fourth RTX infusion, including abdominal pain, hypotension, and bright red blood per rectum. Computed tomography of the abdomen and pelvis with contrast revealed pancolonic mural wall thickening without perforation. Prompt treatment with vasopressors and intravenous fluids led to symptom resolution within 24 hours. We highlighted the importance of recognizing RTX-induced colitis and discussed and depicted immunological dysregulation mechanisms involved.

Anti-CD20 monoclonal antibody (mAb) therapy and colitis: A case series and review

The US Food and Drug Administration (FDA) recently issued a warning regarding ocrelizumab due to reports of colitis among patients taking this medication. Since it is the only FDA-approved therapy for primary progressive multiple sclerosis (PPMS), further research on this adverse event is necessary, and healthcare professionals should be informed of potential treatment options. In this review, we summarize the available data on the incidence of inflammatory colitis associated with anti-CD20 monoclonal antibodies (mAbs), such as ocrelizumab and rituximab, used in MS treatment. Although the exact pathophysiology of anti-CD20-induced colitis remains unknown, immunological dysregulation through treatment-mediated B-cell depletion has been proposed as a possible mechanism. Our study highlights the importance of clinicians being aware of this potential side effect, and patients taking these medications should be closely monitored for any new-onset gastrointestinal symptoms or diarrheal illness. Research indicates that prompt intervention with endoscopic examination and medical or surgical therapies can ensure timely and effective management, thus improving patient outcomes. However, large-scale studies are still needed to determine the associated risk factors and to establish definitive guidelines for the clinical evaluation of MS patients on anti-CD20 medications.

Rituximab-Induced Colitis and Esophagitis in a Patient With Granulomatosis With Polyangiitis

Granulomatosis with polyangiitis (GPA) is a small vessel vasculitis that affects many organ systems with varying disease severity. GPA commonly affects the sinuses and lung parenchyma. However, GPA can affect the gastrointestinal tract and may present as colitis. Immunosuppressive therapy, like rituximab (RTX), is used for the management of this disease. Rituximab is generally well-tolerated but has rare side effects that have been shown to mimic colitis in inflammatory diseases. Our case is a 44-year-old female with a history of GPA who presented with dysphagia, abdominal pain, and diarrhea. The patient received a maintenance dose of RTX six months before the presentation. The patient was seronegative for anti-neutrophilic cytoplasmic antibodies against proteinase 3 (PR3 ANCA). Infectious etiology was ruled out. Esophagogastroduodenoscopy (EGD) and colonoscopy showed esophageal bleeding ulcers and diffuse colonic inflammation, respectively. Pathology was consistent with esophagitis and colitis. Colonic mucosal biopsy failed to show evidence of vasculitis. The patient was treated with sucralfate and intravenous pantoprazole with an improvement in the symptoms. The repeat endoscopy on an outpatient basis showed the patient had full mucosal healing, including histological healing. Our patient likely had rituximab-induced colitis and esophagitis.

B cell expansion hinders the stroma-epithelium regenerative cross talk during mucosal healing

Therapeutic promotion of intestinal regeneration holds great promise, but defining the cellular mechanisms that influence tissue regeneration remains an unmet challenge. To gain insight into the process of mucosal healing, we longitudinally examined the immune cell composition during intestinal damage and regeneration. B cells were the dominant cell type in the healing colon, and single-cell RNA sequencing (scRNA-seq) revealed expansion of an IFN-induced B cell subset during experimental mucosal healing that predominantly located in damaged areas and associated with colitis severity. B cell depletion accelerated recovery upon injury, decreased epithelial ulceration, and enhanced gene expression programs associated with tissue remodeling. scRNA-seq from the epithelial and stromal compartments combined with spatial transcriptomics and multiplex immunostaining showed that B cells decreased interactions between stromal and epithelial cells during mucosal healing. Activated B cells disrupted the epithelial-stromal cross talk required for organoid survival. Thus, B cell expansion during injury impairs epithelial-stromal cell interactions required for mucosal healing, with implications for the treatment of IBD.

Gut inflammation induced by drugs: Can pathology help to differentiate from inflammatory bowel disease?

Drug‐induced mucosal injury (DIMI) in the gastrointestinal tract is important to recognise, partly because cessation of the culprit agent alone may result in resolution of symptoms. An ever‐growing list of medications, including newer immunotherapeutic agents and targeted therapies, can cause gastrointestinal inflammation of varying severity. However, the diagnosis of DIMI is challenging, as a single drug can induce a variety of histopathological patterns of injury including acute colitis, chronic colitis, microscopic colitis, apoptotic colopathy, and ischaemic‐type colitis. An additional consideration is the potential clinical, endoscopic and histological overlap of DIMI with gastrointestinal mucosal injury secondary to other entities such as inflammatory bowel disease (IBD). We discuss DIMI of the gastrointestinal tract with an emphasis on histological patterns that mimic IBD, histological features which may distinguish the two entities, and the diagnostic role and limitations of the pathologist.

Histologic Findings and Tissue B-Cell Depletion in Endoscopic Mucosal Biopsy Specimens of the Gastrointestinal Tract After Treatment With Rituximab

OBJECTIVES

Rituximab (RTX) is associated with variable adverse gastrointestinal (GI) events. However, the histologic correlate in affected patients is not well defined.

METHODS

Patients (n = 93) who had received RTX and undergone endoscopic biopsies were identified. CD20 and PAX5 immunostains were performed on biopsy specimens showing inflammatory pathology (group A, 36 patients) and 35 of 57 noninflammatory biopsies (group B) that were taken within 1 year from the last RTX infusion. Histologic findings were correlated with tissue B-cell depletion (CD20/PAX5-/-).

RESULTS

B cells were depleted in 12 (33%) of 36 group A biopsy specimens. After excluding biopsies taken more than 1 year from the last RTX infusion, the frequencies of tissue B-cell depletion were similar between group A (12/26; 46.2%) and group B (17/35; 48.6%) (P > .05). Also, the frequencies of inflammatory pathology were not statistically different whether B cells were depleted or not (P > .05). In group A with tissue B-cell depletion (n = 12), causality was indicated in two (17%) cases showing lymphocytic colitis pattern of injury (LCPI).

CONCLUSIONS

In RTX-treated patients, tissue B-cell depletion does not appear to be the main cause of inflammatory pathology in the GI tract. A minor subset, however, develops histologic evidence of potential RTX-induced effect, notably in the form of LCPI.

Therapeutic agents affecting the immune system and drug-induced inflammatory bowel disease (IBD): A review on etiological and pathogenetic aspects

In recent years, therapeutic agents affecting the immune system have been largely implemented in the treatment of various hematological, rheumatological and dermatological disorders. Their clinical use has offered important benefits for affected patients and has also ameliorated clinical outcome and prognosis in many cases. Nonetheless, as any treatment, the use of these drugs may be associated with side effects. One of the target organs in such cases is the gastrointestinal tract. In particular, the exacerbation or the onset of inflammatory bowel disease (IBD) in treated patients is not infrequent, although the mechanism of action of these agents may be different. In this review we will focus on the use of therapeutic agents affecting the immune system and the development or exacerbation of IBD, with a mention on the possible underlying pathogenetic mechanisms.

Lactobacillus reuteri Alleviates Gastrointestinal Toxicity of Rituximab by Regulating the Proinflammatory T Cells in vivo

Rituximab (RTX) is a widely used anticancer drug with gastrointestinal side effects, such as nausea, vomiting, and diarrhea. The reason for these side effects is still poorly understood. Previous studies have reported that the intestinal microbiota is associated with the occurrence of disease and the therapeutic effect of drugs. In this study, we observed mucosal damage, inflammatory cell infiltration and increased intestinal inflammatory factor expression in RTX-treated mice. RTX also changed the diversity of the intestinal microbiota in mice, and decreased abundance of Lactobacillus reuteri was observed in RTX-treated mice. Further experiments revealed that intragastric administration of L. reuteri in RTX-treated mice attenuated the intestinal inflammatory response induced by RTX and regulated the proportion of helper T (Th) cells. In conclusion, our data characterize the effect of the intestinal microbiota on RTX-induced intestinal inflammation, suggesting that modifying the gut microbiota may represent a positive strategy for managing adverse reactions.

Immunosuppressive drugs modes of action

The innate and adaptive immune systems work as a complex interplay between different cell types, involving cytokines and chemokines mediating extracellular and paracrine effects. At the intracellular level, the inflammatory cascade is mediated by multifaceted processes that have been better described in the last 10 years. Immunosuppressive agents available in clinical practice act at different points of those cascades at the intracellular or extracellular level. Those drugs can mediate their effects on one or more cell types finally limiting inflammation and immune responses to antigens. Every immunosuppressive agent is characterized by intrinsic toxicity and side effects that may be due to the same therapeutic pathways or to off-target secondary effect of each molecule. We will here review the mechanisms of action of the most widely used immunosuppressive agents in the field of solid organ transplantation and autoimmune disorders, describing the mechanisms underlying both the therapeutic and secondary effects.

Rituximab-induced Ileocolitis in a Patient with Gastric MALToma: A Case Report and Literature Review

Rituximab (RTX) is effective for treating cancer, but reports of RTX-associated enterocolitis are limited. We herein report the case of a 65-year-old man who developed RTX-induced ileocolitis. He was diagnosed with gastric mucosa-associated lymphoid tissue lymphoma (MALToma) and treated with RTX. He complained of bloody diarrhea after RTX. Mucosal inflammation on colonoscopy indicated RTX-induced ileocolitis. He was treated with corticosteroids, and his symptoms improved. We reviewed the RTX-associated gastrointestinal adverse events and classified the features into ulcerative colitis, Crohn's disease, microscopic colitis, and ileocolitis. To our knowledge, this is the first case of a Japanese patient who developed RTX-induced ileocolitis.

Use of rituximab in adults with relapsing-remitting multiple sclerosis: a systematic literature review

Objective: Rituximab is used as an off-label treatment for relapsing-remitting multiple sclerosis (RRMS); however, the comparative efficacy and safety of rituximab versus currently licensed disease-modifying drugs (DMDs) for RRMS is unknown. A systematic literature review was conducted to evaluate the available data pertaining to efficacy and safety of rituximab in adult patients with RRMS and highly active relapsing multiple sclerosis (HA-RMS); data quality was critically assessed via risk of bias (RoB) assessment.Methods: Biomedical literature databases were searched until mid-2018 and key proceedings were searched from 2016 to 2018. Critical appraisal of non-randomized studies was conducted using the Cochrane RoB assessment tool; randomized controlled trials (RCTs) were appraised using comprehensive assessment criteria based on the NICE guidelines.Results: Thirty-eight unique studies based on 49 publications were identified: 25 RRMS studies (one RCT) and 13 HA-RMS studies (no RCTs). The evidence among patients with RRMS generally favored rituximab in comparison to placebo (relapse rate) and interferons/glatiramer acetate (relapse rate and disability progression), although much of the non-randomized data were descriptive and/or not statistically significant. In comparison to placebo, rituximab was associated with a greater risk of adverse events. Two-thirds of the non-randomized RRMS studies were associated with critical/serious RoB; the single RCT was associated with low RoB. Furthermore, all of the non-randomized HA-RMS studies were associated with critical/serious RoB.Conclusions: Available evidence of off-label rituximab use for the treatment of patients with RRMS suggests generally favorable efficacy versus placebo and interferons/glatiramer acetate; however, the poor quality of the included studies limits any robust conclusions.

Clinical Features of Rituximab-associated Gastrointestinal Toxicities

BACKGROUND

Rituximab is effective in treating several cancers. Little is known about gastrointestinal adverse events associated with rituximab. We describe the clinical, endoscopic, and histologic features of rituximab-associated colitis (RC) at a tertiary care cancer center.

METHODS

We conducted a retrospective study of cancer patients who had received rituximab and had undergone a colonoscopy between 2000 and 2018. Patients with competing etiologies for colitis were excluded.

RESULTS

Of the 13,717 patients who had received rituximab during the study period, 1660 had undergone colonoscopy. Among them, 70 (4%) had RC. Median time from rituximab treatment to RC onset was 181 days. Fifty-three patients had clinical gastrointestinal symptoms: 39 had diarrhea, 19 had abdominal pain, 11 had blood per rectum, and 5 had a concurrent fever. The median duration of symptoms was 21 days. Fifty patients (71%) received treatment for RC: immunosuppressive therapy in 12, antimicrobial agents in 21, antimotility agents in 42, and supportive care in 42. Nine patients had mucosal ulceration on endoscopy, and 52 had features of active inflammation on histology. Thirty-nine patients needed hospital admission, and 2 needed intensive care unit admission. One patient had colonic perforation that required surgical intervention. Patients who had abnormal endoscopic findings needed more frequent hospitalization (P=0.024) and more treatment for RC (P=0.001).

CONCLUSIONS

RC is usually a mild disease requiring supportive care only. Nonetheless, on rare occasions, it can be severe enough to lead to colonic perforation and intensive care unit admission. Steroids used with the chemotherapeutic regimen can hamper RC severity.

The current state of the art for biological therapies and new small molecules in inflammatory bowel disease

The emergence of biologic therapies is arguably the greatest therapeutic advance in the care of inflammatory bowel disease (IBD) to date, allowing directed treatments targeted at highly specific molecules shown to play critical roles in disease pathogenesis, with advantages in potency and selectivity. Furthermore, a large number of new biologic and small-molecule therapies in IBD targeting a variety of pathways are at various stages of development that should soon lead to a dramatic expansion in our therapeutic armamentarium. Additionally, since the initial introduction of biologics, there have been substantial advances in our understanding as to how biologics work, the practical realities of their administration, and how to enhance their efficacy and safety in the clinical setting. In this review, we will summarize the current state of the art for biological therapies in IBD, both in terms of agents available and their optimal use, as well as preview future advances in biologics and highly targeted small molecules in the IBD field.