Sarcoidosis following successful treatment of pemphigus vulgaris with rituximab: a rituximab-induced reaction further supporting B-cell contribution to sarcoidosis pathogenesis?

Sarcoid-Like Reaction in the Kidney Following Rituximab for Mantle Lymphoma in a 60-Year-Old Man

The sarcoid-like reaction is a rare autoinflammatory disease that can affect lymph nodes or organs but does not meet the diagnostic criteria for systemic sarcoidosis. Several drug classes have been associated with the development of a systemic sarcoid-like reaction, which defines drug-induced sarcoidosis-like reactions and can affect a single organ. Anti-CD20 antibodies (rituximab) have rarely been reported as responsible for this reaction and this adverse effect has mainly been described during the treatment of Hodgkin's lymphoma. We report a unique case of a sarcoid-like reaction complicating rituximab following the treatment of a mantle cell lymphoma and interesting only the kidney. The 60-year-old patient presented with severe acute renal failure 6 months after the end of his r-CHOP protocol and the urgent renal biopsy revealed acute interstitial nephritis rich in granulomas without caseous necrosis. After ruling out other causes of granulomatous nephritis, a sarcoid-like reaction was retained since infiltration was limited to the kidney. The temporal relationship between rituximab administration and the sarcoid-like reaction onset in our patient supported the diagnosis of a rituximab-induced sarcoidosis-like reaction. Oral corticosteroid treatment led to rapid and lasting improvement in renal function. Clinicians should be warned of this adverse effect and regular and prolonged monitoring of renal function should be recommended during the follow-up of patients after the end of treatment with rituximab.

Innate and Adaptive Immunity in Noninfectious Granulomatous Lung Disease

Sarcoidosis and chronic beryllium disease are noninfectious lung diseases that are characterized by the presence of noncaseating granulomatous inflammation. Chronic beryllium disease is caused by occupational exposure to beryllium containing particles, whereas the etiology of sarcoidosis is not known. Genetic susceptibility for both diseases is associated with particular MHC class II alleles, and CD4⁺ T cells are implicated in their pathogenesis. The innate immune system plays a critical role in the initiation of pathogenic CD4⁺ T cell responses as well as the transition to active lung disease and disease progression. In this review, we highlight recent insights into Ag recognition in chronic beryllium disease and sarcoidosis. In addition, we discuss the current understanding of the dynamic interactions between the innate and adaptive immune systems and their impact on disease pathogenesis.

The Role of Diverse Immune Cells in Sarcoidosis

Sarcoidosis is a systemic inflammatory disorder of unknown etiology characterized by tissue infiltration with macrophages and lymphocytes and associated non-caseating granuloma formation. The disease primarily affects the lungs. Patients suffering from sarcoidosis show a wide range of clinical symptoms, natural history and disease outcomes. Originally described as a Th1-driven disease, sarcoidosis involves a complex interplay among diverse immune cells. This review highlights recent advances in the pathogenesis of sarcoidosis, with emphasis on the role of different immune cells. Accumulative evidence suggests Th17 cells, IFN-γ-producing Th17 cells or Th17.1 cells, and regulatory T (Treg) cells play a critical role. However, their specific actions, whether protective or pathogenic, remain to be clarified. Macrophages are also involved in granuloma formation, and M2 polarization may be predictive of fibrosis. Previously neglected cells including B cells, dendritic cells (DCs), natural killer (NK) cells and natural killer T (NKT) cells were studied more recently for their contribution to sarcoid granuloma formation. Despite these advances, the pathogenesis remains incompletely understood, indicating an urgent need for further research to reveal the distinct immunological events in this process, with hope to open up new therapeutic avenues and if possible, to develop preventive measures.

Association of spondyloarthritis and sarcoidosis: A retrospective observational population-based matched cohort study

OBJECTIVES

To investigate the association between spondyloarthritis (SpA) and sarcoidosis.

METHODS

An observational retrospective population-based matched cohort study was conducted. Using data from the Spanish Minimum Basic Data Set. All the admissions of patients with SpA reported between 1999 and 2015 were analysed and a control group matched by age, sex and year of admission was selected. Crude and age- and sex-adjusted incidence rates for sarcoidosis were calculated. Generalized linear models were used for trend analysis and unconditional logistic regression models for calculating crude and adjusted odds ratios (ORs) to assess the association between sarcoidosis and SpA.

RESULTS

The study database contained data on 214,280 hospitalisations: 107,140 admissions of patients with SpA and 107,140 of patients without SpA. Overall, 220 of the admissions were of patients with sarcoidosis: 133 (0.12%) in the SpA group and 87 (0.08%) in the non-SpA group (P<0.05). The incidence rates of sarcoidosis were 2.68 and 1.64 per 100,000 per year in the SpA and non-SpA groups, respectively. The trend was similar in the two cohorts. Regarding potential associations between SpA and sarcoidosis, the crude and adjusted ORs were 1.52 (95% CI: 1.16-2.01) and 1.50 (95% CI: 1.14-1.97) overall in patients with SpA, with adjusted ORs of 1.42 (95% CI: 1.03-1.94) and 1.81 (95% CI: 1.29-2.55) in patients with ankylosing spondylitis and psoriatic arthritis, respectively.

CONCLUSIONS

There is a relationship that is not due to chance between sarcoidosis and SpA and specifically that sarcoidosis is significantly associated with ankylosing spondylitis and psoriatic arthritis.

Rituximab for the Treatment of Refractory Cardiac Sarcoidosis-A Single Center Experience

OBJECTIVE

To examine the effect of anti-B cell therapy (rituximab) on cardiac inflammation and function in corticosteroid-refractory cardiac sarcoidosis.

BACKGROUND

Cardiac sarcoidosis (CS) is a rare cause of cardiomyopathy characterized by granulomatous inflammation involving the myocardium. While typically responsive to corticosteroid treatment, there is a critical need for identifying effective steroid-sparing agents for disease control. Despite growing evidence on the role of B-cells in the pathogenesis of sarcoidosis, there is limited data on the efficacy of anti-B cell therapy, specifically rituximab, for controlling CS.

METHODS

We reviewed the clinical experience at a tertiary care referral center of all patients with CS who received rituximab after failing to improve with initial immunosuppression therapy, which included corticosteroids. Fluorodeoxyglucose positron emission tomography (FDG-PET/CT) images before and after rituximab treatment were evaluated. All images were interpreted by 2 experienced nuclear medicine trained physicians.

RESULTS

We identified seven patients, (5 men, 2 women; mean age at diagnosis, 49.0±7.9 years) with active cardiac sarcoidosis who were treated with rituximab. The median length of follow-up was 5.1 years. All individuals, but 1, had received prior steroid-sparing agents in addition to corticosteroids. Rituximab was administered either as 1000 mg IV x 1 or x 2 doses, separated by 2 weeks. Repeat dosing, if appropriate, was considered after 6 months. All tolerated the infusions well.Inflammation as assessed by maximum SUV on cardiac FDG PET/CT uptake significantly decreased in 6 of 7 patients (median 6.0 to 4.5, Wilcoxon signed rank z: -1.8593, W: 3), whereas left ventricular ejection fraction improved or stabilized in 4 patients but decreased in 3. Mean left ventricular ejection fraction (LVEF) was 40.1% and 43.3% before and after treatment respectively (p=0.28). Three patients reported improved physical capacity, and 5 patients showed improved arrhythmic burden on Holter monitoring or ICD interrogation. One patient subsequently developed fungal catheter-associated infection and sepsis requiring discontinuation.

CONCLUSIONS

Rituximab was well tolerated and appeared to decrease inflammation, as assessed by cardiac FDG PET/CT scan, in all but 1 patient with active CS. These data suggest that rituximab may be a promising therapeutic option for CS, which deserves further study.

Ustekinumab-induced Sarcoidosis in a Patient with Psoriatic Arthritis

BACKGROUND

Psoriatic Arthritis (PsA) is a chronic inflammatory disease that may affect different joints. Sarcoidosis is a Th-1 cell-related chronic granulomatous disease characterized by non-caseating granuloma formation. The coexistence of both the diseases is a rare entity. Ustekinumab, an IL12 / 23 inhibitor, has shown efficacy and safety in the treatment of PsA.

OBJECTIVE

This study presents a case with ustekinumab-induced sarcoidosis in a patient with PsA.

CASE REPORT

A 52 years old female patient with complaints of pain and swelling of the wrists, MCP, PIP and DIP joints and skin lesions was referred to our Rheumatology clinic. On her medical history, she had been under follow up for 5 years with the diagnosis of psoriasis and one year ago, she started to receive ustekinumab prescribed by a dermatologist. On physical examination, she had psoriasis skin lesions and arthritis of both wrists, MCP, PIP, DIP joints. Bilateral hilar lymphadenopathies were detected in the chest X-ray and thorax computed tomography. In laboratory tests, acute phase reactants and serum angiotensin-converting enzyme levels were high. Endobronchial ultrasonography biopsy was performed and non-caseating granuloma consistent with sarcoidosis was reported. Ustekinumab was discontinued, methotrexate and low-dose corticosteroid were started. The patient was clinically stable in the 6th month of the treatment and the findings were regressed.

CONCLUSION

Sarcoidosis development appears to be a new paradoxical effect of ustekinumab therapy, being another biological agent.

Biologic and advanced immunomodulating therapeutic options for sarcoidosis: a clinical update

Introduction: Sarcoidosis is a multi-organ disease with a wide range of clinical manifestations and outcomes. A quarter of sarcoidosis patients require long-term treatment for chronic disease. In this group, corticosteroids and cytotoxic agents be insufficient to control diseaseAreas covered: Several biologic agents have been studied for treatment of chronic pulmonary and extra-pulmonary disease. A review of the available literature was performed searching PubMed and an expert opinion regarding specific therapy was developed.Expert opinion: These agents have the potential of treating patients who have progressive disease. Many of these agents have different mechanisms of action, response rates, and toxicity profiles.

Clinical and biological activity of rituximab in the treatment of pemphigus

B-cells are major effector cells in autoimmunity since they differentiate into plasmocytes that produce pathogenic auto-antibody such as anti-desmoglein antibodies in pemphigus patients. Major advances were obtained using whole B-cell depleting therapies including anti-CD20 antibodies in refractory pemphigus patients that lead to rituximab approval in pemphigus patients in EU and USA. This review summarizes the data supporting the efficacy of rituximab in pemphigus and provides an overview of the reported immunological changes underlying its therapeutic action. Short and long-term remission in pemphigus is explained by the removal of autoreactive B-cells involved in the production of pathogenic IgG auto-antibodies and by enhancement of the appearance of regulatory B-cells that could maintain long term immune tolerance.

Key Players and Biomarkers of the Adaptive Immune System in the Pathogenesis of Sarcoidosis

Sarcoidosis is a systemic inflammatory disease characterized by development of granulomas in the affected organs. Sarcoidosis is often a diagnosis of exclusion, and traditionally used tests for sarcoidosis demonstrate low sensitivity and specificity. We propose that accuracy of diagnosis can be improved if biomarkers of altered lymphocyte populations and levels of signaling molecules involved in disease pathogenesis are measured for patterns suggestive of sarcoidosis. These distinctive biomarkers can also be used to determine disease progression, predict prognosis, and make treatment decisions. Many subsets of T lymphocytes, including CD8⁺ T-cells and regulatory T-cells, have been shown to be dysfunctional in sarcoidosis, and the predominant CD4⁺ T helper cell subset in granulomas appears to be a strong indicator of disease phenotype and outcome. Studies of altered B cell populations, B cell signaling molecules, and immune complexes in sarcoidosis patients reveal promising biomarkers as well as possible explanations of disease etiology. Furthermore, examined biomarkers raise questions about new treatment methods and sarcoidosis antigens.

Drug-induced sarcoidosis: an overview of the WHO pharmacovigilance database

BACKGROUND

There is a documented association between drug exposure and sarcoidosis-like reactions. In this study, we used the largest pharmacovigilance database to describe drug-induced sarcoidosis.

METHODS

Data were collected from the World Health Organization (WHO) pharmacovigilance database (VigiBase). We excluded steroids and vaccines from the analysis. The primary end-point was the lower end-point of the 95% credibility interval for the information component (IC₀₂₅ ).

RESULTS

A total of 127 reports had significant IC₀₂₅ values for drug-induced sarcoidosis, and 110 were included in the final analysis, accounting for 2425 adverse drug reactions. Overall, 2074 (85.5%) reactions were considered 'serious' and 86 (3.5%) were fatal. Most of the drugs that led to sarcoidosis adverse reactions were TNF-alpha antagonists, interferon or peg-interferon therapeutics, and immune checkpoint inhibitors. Other biologic drugs were less frequently associated with sarcoidosis adverse events. Cancer-targeted therapies such as BRAF or MEK inhibitors were associated with sarcoidosis reactions in 37 cases. Pulmonary hypertension drugs were also reported for drug-induced sarcoidosis. Amongst the 55 drugs considered as potential sarcoidosis inducers, 25 (45.4%) were never reported in Medline as drug-induced sarcoidosis.

CONCLUSIONS

We provide a detailed list of suspected drugs associated with drug-induced sarcoidosis that will improve the recognition of this drug-induced adverse event.

Scar sarcoidosis following rituximab therapy

Drug-induced sarcoidosis has been rarely described but it constitutes a potential side effect of immunomodulatory medications. We report a case of rituximab-induced scar sarcoidosis and review similar published cases. Although there is evidence of B-cell dysregulation in the pathogenesis of sarcoidosis, the use of rituximab for this disease needs to be carefully evaluated based on reports of worsening and de novo development of sarcoidosis after rituximab therapy.

Immune response biomarkers as indicators of sarcoidosis presence, prognosis, and possible treatment: An Immunopathogenic perspective

Sarcoidosis has been a disease of puzzling occurrence and clinical course. Multiple immunological markers have been noted to be altered within sarcoidosis, however there is variable consistency among these reports. Previous studies have shown sarcoidosis to be a primary T cell-mediated disease, yet new data concerning B cell and mycobacterial involvement have been brought to light. The possibility of a uniform biomarker to characterize sarcoidosis presence, severity and prognosis greatly increases the movement towards directed and specialized treatment for this rare disease.

Immune response patterns in non-communicable inflammatory skin diseases

Non-communicable inflammatory skin diseases (ncISD) such as psoriasis or atopic eczema are a major cause of global disease burden. Due to their impact and complexity, ncISD represent a major challenge of modern medicine. Dermatology textbooks describe more than 100 different ncISD based on clinical phenotype and histological architecture. In the last decades, this historical description was complemented by increasing molecular knowledge - and this knowledge is now being translated into specific therapeutics. Combining the enormous advances made in lymphocyte immunology and molecular genetics with clinical and histological phenotyping reveals six immune response patterns of the skin - type I immune cells cause the lichenoid pattern characterized by immune-mediated cell death of keratinocytes; type II immune cells underlie the eczematous pattern with impaired epidermal barrier, infection and eosinophils as well as the bullous pattern with loss of epithelial integrity; Th17 cells and ILC3 mediate the psoriatic pattern characterized by acanthosis, high metabolic activity and neutrophils; dysbalance of regulatory T cells causes either the fibrogenic pattern with rarefication of cells and dermal thickening or the granulomatous pattern defined by formation of granulomas. With more and more specific therapeutic agents approved, classifying ncISD also according to their immune response pattern will become highly relevant. This review defines the six immune response patterns of ncISD and highlights therapeutic strategies targeting key lymphocyte mediators.