IgA Vasculitis Developed as an Adverse Effect of Tofacitinib Taken for Rheumatoid Arthritis

Application of JAK inhibitors in paradoxical reaction through immune-related dermatoses

Biologics play a positive and effective role in the treatment of immune-related dermatoses. However, many other immune-related diseases have also manifested along with biologics treatment. Paradoxical reaction through immune-related dermatoses refer to the new onset or exacerbation of other immune-mediated dermatoses (mainly psoriasis and atopic dermatitis) after biologics treatment of inflammatory dermatoses (mainly psoriasis and atopic dermatitis), such as new atopic dermatitis (AD) in psoriasis (PsO) treatment and new PsO in AD treatment. A common genetic background and Inflammatory pathway are possible pathogenesis. Faced with paradoxical reactions, the choice of therapy needs to be directed toward therapies effective for both diseases, such as Janus kinase (JAK) inhibitors. The Janus kinase and signal transducer and activator of transcription (JAK-STAT) pathway plays an important role in the inflammatory pathway, and has been widely used in the treatment of AD and PsO in recent years. This article focuses on JAK inhibitors such as tofacitinib, baricitinib, ruxolitinib, Abrocitinib, upadacitinib, and deucravacitinib, to explore the possible application in treatment of paradoxical reactions. Common side effects, baseline risk factors and safety use of JAK inhibitors were discussed.

Role of JAK-STAT signaling pathway in pathogenesis and treatment of primary Sjögren's syndrome

ABSTRACT

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease with high prevalence and possible poor prognosis. Though the pathogenesis of pSS has not been fully elucidated, B cell hyperactivity is considered as one of the fundamental abnormalities in pSS patients. It has long been identified that Janus kinases-signal transducer and activator of transcription (JAK-STAT) signaling pathway contributes to rheumatoid arthritis and systemic lupus erythematosus. Recently, increasing numbers of studies have provided evidence that JAK-STAT pathway also has an important role in the pathogenesis of pSS via direct or indirect activation of B cells. Signal transducer and activator of transcription 1 (STAT1), STAT3, and STAT5 activated by various cytokines and ribonucleic acid contribute to pSS development, respectively or synergically. These results reveal the potential application of Janus kinase inhibitors for treatment of pSS, which may fundamentally improve the quality of life and prognosis of patients with pSS.

Cutaneous vasculitis associated with molecular tergeted therapies: systematic review of the literature

Cutaneo us vasculitis (CV) has a broad spectrum of etiologies, and drugs are one of the main culprits. With the increasing use of targeted therapies in medicine, especially in rheumatology and oncology, the number of CV cases reported due to these drugs has increased. Therefore, the recognition and treatment of CV associated with targeted agents have become more and more important. In the literature, anti-TNFs (n = 73, 59.5%), secukinumab (n = 7, 6%), rituximab (n = 5, 4%), tocilizumab (n = 1, 0.8%), ustekinumab (n = 8, 6.5%), abatacept (n = 3, 2.4%), Janus kinase inhibitors (n = 3, 2.4%), alemtuzumab (n = 3, 2.4%), and immune checkpoint inhibitors (n = 20, 16%) have been reported as responsible agents. However, our knowledge of the pathogenetic mechanisms is fairly limited, and the standardized management is yet to be established. Furthermore, though it is uncommon, this complication may pose a safety issue. In this manuscript, we reviewed the literature on CV with or without systemic involvement related to targeted agents. We also proposed the pathogenetic mechanisms of these adverse events. Thus, we aimed to make it easier for clinicians to manage similar cases by reviewing the diagnosis and treatment processes.

IgA vasculitis update: Epidemiology, pathogenesis, and biomarkers

Immunoglobulin A vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is the most common systemic vasculitis in children, characterized by diverse clinical manifestations with a wide spectrum ranging from isolated cutaneous vasculitis to systemic involvement. The incidence of IgAV is geographically and ethnically variable, with a prevalence in autumn and winter, suggesting a driving role that genetic and environmental factors play in the disease. Although IgAV has a certain degree of natural remission, it varies widely among individuals. Some patients can suffer from severe renal involvement and even progress to end-stage renal disease. Its pathogenesis is complex and has not been fully elucidated. The formation of galactose-deficient IgA1 (Gd-IgA1) and related immune complexes plays a vital role in promoting the occurrence and development of IgAV nephritis. In addition, neutrophil activation is stimulated through the binding of IgA to the Fc alpha receptor I expressed on its surface, resulting in systemic vascular inflammation and tissue damage. Starting from the epidemiological characteristics, this article will review the role of immunological factors such as Gd-IgA1, autoantibodies, circulating immune complexes, complement system, cellular immunization, and the contributions of environmental and genetic factors in the pathogenesis of IgAV, and conclude with the major biomarkers for IgAV.

Adult-Onset IgA Vasculitis Presenting as an Unusual Rash and Pancolitis

A 47-year-old female presented with complaints of abdominal pain and a history of new-onset maculopapular rash. A workup including laboratory and imaging studies, colonoscopy, and biopsy was performed that led to the diagnosis of adult-onset IgA vasculitis. The patient responded well to intravenous methylprednisolone and was followed up as an outpatient where she continued with oral methylprednisolone and azathioprine. This case is noteworthy for the unusual adult-onset presentation with primarily gastrointestinal symptoms and atypical rash pattern. Furthermore, while very effective in this patient, the use of corticosteroids is a treatment decision that has some controversy in the current literature.

Complete remission of tip lesion variant focal segmental glomerulosclerosis (FSGS) with the Janus Kinase (JAK) inhibitor tofacitinib

A 67-year-old woman with transverse myelitis and seizure disorder secondary to suspected central nervous system (CNS) systemic lupus erythematosus (SLE) and seropositive rheumatoid arthritis had two episodes of severe nephrotic syndrome 15 years apart. She underwent a renal biopsy in both episodes, showing tip lesion variant focal segmental glomerulosclerosis (FSGS). The patient responded both times to prednisone treatment, achieving a complete remission within 2 months in the first episode and remission 4 months in the second episode. A year after her second episode, the patient had a third episode of severe nephrotic syndrome. She achieved an equally rapid complete remission in 3 months without steroid treatment, as she was concomitantly treated with the Janus Kinase (JAK) inhibitor tofacitinib for a flare of rheumatoid arthritis. This case report suggests that JAK inhibitors may have therapeutic use in FSGS, which is supported by experimental data in the medical literature.

Tofacitinib-Induced Antineutrophil Cytoplasmic Antibodies (ANCA)-Associated Vasculitis With Crescentic Glomerulonephritis

Antineutrophil cytoplasmic antibodies (ANCA) vasculitis is common after the age of 50 years but it can occur at any age. There is a slight male preponderance and it is more common in Whites than Blacks but the black race confers a worse prognosis. The clinical features of ANCA vasculitis vary considerably. The manifestation of the disease depends on the organs affected, the chronicity of the disease, and how quiescent it is. Non-specific symptoms of malaise, fatigue, fever, and weight loss are common. Crescentic glomerulonephritis with focal necrosis is usually the pathology underlying renal disease. Manifestations of renal disease include hematuria and proteinuria which may progress to renal failure.

We present a case of a 75-year-old female who presented with acute worsening of renal function and nephrotic-range proteinuria with positive testing for p-ANCA after the recent commencement of treatment with tofacitinib. This prompted a suspicion of ANCA-vasculitis. The patient was started on pulse dose steroids and rituximab after kidney biopsy confirmation of ANCA-vasculitis with crescentic glomerulonephritis.

Biologics and Targeted Synthetic Drugs Can Induce Immune-Mediated Glomerular Disorders in Patients with Rheumatic Diseases: An Updated Systematic Literature Review

Objective

Our objective was to update the understanding of the development of paradoxical immune-mediated glomerular disorders (IGDs) in patients with rheumatic diseases treated with biologics and targeted synthetic drugs (ts-drugs).

Methods

A systematic literature review was performed by searching PubMed for articles published between 1 January 2014 and 1 January 2020 reporting on the development of IGD in adult patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis or systemic lupus erythematosus (SLE) who were receiving biologics or ts-drugs. IGDs were classified on the basis of clinical, laboratory and histopathological data as (1) glomerulonephritis associated with systemic vasculitis (GNSV), (2) isolated autoimmune renal disorder (IARD) or (3) glomerulonephritis in SLE and in lupus-like syndrome (GNLS). The World Health Organization-Uppsala Monitoring Centre (WHO-UMC) system for standardized case causality assessment was applied to evaluate the causal relationship between IGD and specific drugs. The classification was based on a six-category scale, where the “certain” and “probable” categories were deemed clinically relevant relationships.

Results

The literature search retrieved 875 articles. Of these, 16 articles reported IGD data, for a total of 25 cases. According to the WHO-UMC assessment, the strength of the causal relationship between IGDs and investigated drugs was higher for anti-tumor necrosis factor-α agents (a clinically relevant relationship was found in four of six cases), abatacept (one of two cases), tocilizumab (two cases), ustekinumab (one case) and tofacitinib (one case) than for rituximab (nine cases), belimumab (three cases) or secukinumab (one case), which showed a weak causal relationship with these paradoxical events. No cases associated with apremilast or baricitinib were found. The retrieved cases were classified as 11 GNLS, seven IARD and seven GNSV.

Conclusions

Biologics and ts-drugs can cause IGDs. These events are rare, and the causative effect of a specific drug is hard to establish. When a patient is suspected of having an IGD, the drug should be discontinued, and treatment for the new-onset renal disorder should be promptly started.

JAK/STAT pathway in pathology of rheumatoid arthritis (Review)

Rheumatoid arthritis (RA) is classified as an inflammatory, chronic autoimmune and disabling disease based on the intricate interplay between environmental and genetic factors. With a prevalence ranging from 0.3 to 1%, RA is the most prevalent inflammatory joint disease observed in adults. Disruption of immune tolerance becomes evident when abnormal stimulation of the innate and adaptive immune system occurs. This cascade of events causes persistent joint inflammation, proliferative synovitis and, ultimately, damage of the underlying cartilage as well as the subchondral bone, leading to permanent joint destruction, deformity and subsequent loss of function. With cytokines being the key to a multitude of biological processes, including inflammation, hematopoiesis and overall immune response, one must inevitably look at the main pathways through which a significant number of those molecules exert their function. Janus kinase/signal transducers and activators of transcription (JAK/STATs) represent one such pathway and, recently, JAK inhibitors (JAKinibs) have shown promise in the treatment of several inflammatory diseases, including RA. This narrative review focuses on the intricate signaling pathways involved as well as on the clinical aspects and safety profiles of JAKinibs approved for the treatment of RA.