Interferon-induced sarcoidosis

The immunopathogenesis of sarcoidosis

Sarcoidosis is a granulomatous multiorgan disease, thought to result from exposure to yet unidentified antigens in genetically susceptible individuals. The exaggerated inflammatory response that leads to granuloma formation is highly complex and involves the innate and adaptive immune system. Consecutive immunological studies using advanced technology have increased our understanding of aberrantly activated immune cells, mediators and pathways that influence the formation, maintenance and resolution of granulomas. Over the years, it has become increasingly clear that disease immunopathogenesis can only be understood if the clinical heterogeneity of sarcoidosis is taken into consideration, along with the distribution of immune cells in peripheral blood and involved organs. Most studies offer an immunological snapshot during disease course, while the cellular composition of both the circulation and tissue microenvironment may change over time. Despite these challenges, novel insights on the role of the immune system are continuously published, thus bringing the field forward. This review highlights current knowledge on the innate and adaptive immune responses involved in sarcoidosis pathogenesis, as well as the pathways involved in non-resolving disease and fibrosis development. Additionally, we describe proposed immunological mechanisms responsible for drug-induced sarcoid like reactions. Although many aspects of disease immunopathogenesis remain to be unraveled, the identification of crucial immune reactions in sarcoidosis may help identify new treatment targets. We therefore also discuss potential therapies and future strategies based on the latest immunological findings.

Increased serum interferon activity in sarcoidosis compared to that in tuberculosis: Implication for diagnosis?

Objectives

In this study, we measured serum interferon (IFN) levels and activity in patients with sarcoidosis and tuberculosis (TB) with and without uveitis. We aimed to understand the role of IFN in the pathophysiology of both conditions and explore its potential as a discriminating marker for these clinically similar diseases.

Methods

Sera from an Indonesian TB and a Dutch sarcoidosis cohort were used in the analysis. IFNα2 and IFNγ concentrations were measured using Simoa® and Luminex assays, respectively. Serum IFN activity was assessed by incubating THP-1 cells with patient serum and measuring IFN-stimulated gene transcription using qPCR. Anti-IFNα2 and IFNγ autoantibodies were detected via Luminex assay and tested for neutralizing capacity using a flow cytometry-based signal transducer and activator of transcription (STAT) 1 phosphorylation inhibition assay.

Results

IFNα2 was detected in 74 % and 64 % of patients with sarcoidosis and pulmonary TB, respectively, while IFNγ was found in 78 % and 23 % of patients with sarcoidosis and TB, respectively. For uveitis cases specifically, IFNα2 was detected in 85 % of sarcoid uveitis (SU) and 33 % of tubercular uveitis (TBU) cases. Similarly, IFNγ was detected in 69 % of SU and 17 % of TBU cases. IFNγ serum concentrations were higher in sarcoidosis than that in TB patients (p < 0.0001). Focusing on patients with uveitis, SU showed increased IFNα2 (p = 0.004) and IFNγ (p < 0.002) serum concentrations compared to that in TBU. Notably, TBU displayed significantly reduced IFNα2 concentrations compared to that in healthy controls (p = 0.006). These results align with the increased interferon stimulated gene (ISG) transcriptional upregulation observed in THP-1 cells stimulated with serum from patients with sarcoidosis. Elevated levels of non-neutralizing anti-IFN autoantibodies were observed in patients with TB; however, these levels were similar to those observed in geographically matched healthy Indonesian controls.

Conclusion

Our results suggest decreased serum levels and activity of type I and II IFN in TB compared to those in sarcoidosis. This is indicative of distinct pathophysiological processes in these highly clinically similar diseases. We propose that the assessment of serum IFN levels and IFN activity has the potential to distinguish between sarcoidosis/SU and TB/TBU.

Acute Fibrinous Anterior Uveitis in a Patient Treated With Topical Interferon-α2b for Ocular Surface Squamous Neoplasia With Uveitis Susceptibility

PURPOSE

To report a case of fibrinous acute anterior uveitis associated with topical interferon-α2b (IFN-α2b) treatment for ocular surface squamous neoplasia in a patient with HLA-B27 uveitis predisposition.

METHODS

Case report.

RESULTS

We present the case of a 57-year-old man who received topical IFN-α2b as adjuvant therapy for a previously surgically removed ocular surface squamous neoplasia with affected surgical margins. Two weeks after topical IFN-α2b initiation, the patient was diagnosed with fibrinous acute anterior uveitis. Complementary tests to rule out other causes of uveitis resulted to be negative, except for HLA-B27, which tested positive. Response to treatment with topical corticosteroids and cyclopentolate was favorable. As IFN-α2b is considered an immune enhancer and has been widely associated with autoimmune side effects, topical therapy with IFN-α2b was temporally ceased until intraocular inflammation resolved. Topical IFN-α2b was resumed, and during follow-up, no signs of uveitis were detected. The main hypothesis is that IFN-α2b acts as a trigger for intraocular inflammation in individuals with uveitis predisposition.

CONCLUSIONS

Topical IFN-α2b could trigger intraocular inflammation in patients with uveitis susceptibility. It may be reasonable to use IFN-α2b cautiously in patients with a known history of uveitis or uveitis predisposition.

Propionibacterium acnes-associated Sarcoidosis Possibly Initially Triggered by Interferon-alpha Therapy

A 46-year-old woman with uveitis was referred to our respiratory diseases department in July 2018. Her medical history included transient bilateral hilar mediastinal lymphadenopathy (BHL) and multiple pulmonary nodules in May 2013 during pegylated interferon-alpha and ribavirin treatment for chronic hepatitis C infection. Five years post-treatment, chest X-ray revealed BHL and nodular recurrence. A biopsy of the subcutaneous buttock nodules revealed scattered non-caseating epithelioid granulomas with positive PAB immunohistochemical staining. This seem to be the first report of Propionibacterium acnes-associated sarcoidosis possibly initially triggered by interferon-alpha therapy. Understanding the mechanisms underlying interferon-triggered P. acnes-associated sarcoidosis may clarify the sarcoidosis immunopathogenesis.

Hepatic involvement in sarcoidosis

Sarcoidosis is a multisystem granulomatous disease of unknown etiology. Liver is frequently involved in the pathological process. Wide range of clinical manifestations can be seen: from asymptomatic lesion with normal liver function tests to cirrhosis with portal hypertension. Biopsy plays the key role in diagnosis of the hepatic sarcoidosis. It is essential for morphological diagnosis to exclude other causes of granulomatous liver disease, most often - primary biliary cholangitis. Nowadays there are no standard treatment protocols for patients with hepatic sarcoidosis.

Biologics for the treatment of noninfectious uveitis: current concepts and emerging therapeutics

PURPOSE OF REVIEW

There is mounting evidence supporting the use of biologic therapeutics for the management of noninfectious uveitis (NIU). This review highlights: biologics with documented efficacy in NIU; agents with ongoing evaluation for efficacy in uveitis; and therapeutics for which investigation for efficacy in NIU is warranted.

RECENT FINDINGS

The tumor necrosis factor-alpha (TNF-α) inhibitor adalimumab has recently gained approval by the Food and Drug Administration for the treatment of noninfectious intermediate, posterior, and panuveitis. There is mounting evidence supporting the use of tocilizumab and rituximab in NIU. There is developing interest in evaluating the interleukin (IL)-23 inhibitors for efficacy in NIU.

SUMMARY

The TNF-α inhibitors adalimumab and infliximab have the greatest body of data supporting their use in NIU. These agents are considered second-line therapy for most forms of NIU but may be considered first-line therapy for uveitis associated with Behçet's disease and juvenile idiopathic arthritis. The B-cell inhibitor rituximab and the IL-6 inhibitor tocilizumab also have documented efficacy in NIU. Tocilizumab and interferon therapy may be particularly efficacious in the management of uveitic macular edema. The IL-23 inhibitors and janus kinase inhibitors are agents whose efficacy in NIU will likely be determined in the near future.

Sarcoidosis-Like Reactions Induced by Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) are a newly developed component of cancer care that expands the treatment possibilities for patients. Their use has been associated with several immune-related adverse events, including ICI-induced sarcoidosis-like reactions. This article reviews the data concerning ICI-induced sarcoidosis-like reactions currently available in the medical literature. These reactions have been reported in three classes of ICIs: anti-cytotoxic T-lymphocyte associated protein 4 antibodies, programmed death 1 inhibitors and programmed death ligand 1 inhibitors. These reactions are indistinguishable from sarcoidosis with a similar histology, pattern of organ involvement, and pattern of clinical manifestations. The most common locations to observe granulomatous inflammation from these reactions is in intrathoracic locations (the lung and/or mediastinal lymph nodes) and the skin. The median time between initiation of an ICI and the development of a sarcoidosis-like reaction averaged 14 weeks. Clinicians have opted to use corticosteroids and/or discontinue the ICI, or take no action when these reactions have developed. Regardless of whether the clinician performed an intervention or not, these reactions have uniformly improved or resolved after ICI-treatment, which provides additional temporal evidence supporting the presence of a sarcoidosis-like reaction as opposed to sarcoidosis. There is even evidence that the development of an ICI-induced sarcoidosis-like reaction suggests that the ICI is effective as an anti-tumor agent and should be continued. As is the case for sarcoidosis, sarcoidosis-like reactions do not mandate antisarcoidosis therapy, especially if the condition is asymptomatic. When treatment of sarcoidosis-like reaction is required, it may be prudent to continue ICI therapy and add antisarcoidosis therapy because standard antisarcoidosis regimens seem to be effective. Further research into the mechanisms involved in the development of ICI-induced sarcoidosis-like reactions may give insights into the immunopathogenesis of sarcoidosis.

Drug-Induced Sarcoidosis-Like Reactions

A drug-induced sarcoidosis-like reaction (DISR) is a systemic granulomatous reaction that is indistinguishable from sarcoidosis and occurs in a temporal relationship with initiation of an offending drug. DISRs typically improve or resolve after withdrawal of the offending drug. Four common categories of drugs that have been associated with the development of a DISR are immune checkpoint inhibitors, highly active antiretroviral therapy, interferons, and tumor necrosis factor-α antagonists. Similar to sarcoidosis, DISRs do not necessarily require treatment because they may cause no significant symptoms, quality of life impairment, or organ dysfunction. When treatment of a DISR is required, standard antisarcoidosis regimens seem to be effective. Because a DISR tends to improve or resolve when the offending drug is discontinued, this is another effective treatment for a DISR. However, the offending drug need not be discontinued if it is useful, and antigranulomatous therapy can be added. In some situations, the development of a DISR may suggest a beneficial effect of the inducing drug. Understanding the mechanisms leading to DISRs may yield important insights into the immunopathogenesis of sarcoidosis.

A review and update on orphan drugs for the treatment of noninfectious uveitis

Introduction

Uveitis, a leading cause of preventable blindness around the world, is a critically underserved disease in regard to the medications approved for use. Multiple immunomodulatory therapy (IMT) drugs are appropriate for uveitis therapy but are still off-label. These IMT agents, including antimetabolites, calcineurin inhibitors, alkylating agents, and biologic agents, have been designated as “orphan drugs” and are widely used for systemic autoimmune diseases or organ transplantation.

Area covered

The purpose of this paper is to comprehensively review and summarize the approved orphan drugs and biologics that are being used to treat systemic diseases and to discuss drugs that have not yet received approval as an “orphan drug for treating uveitis” by the US Food and Drug Administration (FDA).

Our perspective

IMT, as a steroid-sparing agent for uveitis patients, has shown promising clinical results. Refractory and recurrent uveitis requires combination IMT agents. IMT is continued for a period of 2 years while the patient is in remission before considering tapering medication. Our current goals include developing further assessments regarding the efficacy, optimal dose, and safety in efforts to achieve FDA approval for “on-label” use of current IMT agents and biologics more quickly and to facilitate insurance coverage and expand access to the products for this orphan disease.

Cutaneous Granulomas Associated With Interferon Therapy

Treatment with interferon (IFN) could be associated with variable cutaneous adverse reactions. The aim of this study was to describe the clinicopathological spectrum of cutaneous granulomas associated with IFN therapy and identify the causal relation between IFN therapy and granulomatous reactions. The study included 18 patients (16 males and 2 females) with an average age of 48 years. Clinically, most of the lesions were solitary (83.3%) and located on the face (44.4%) and/or trunk (38.9%). The lesions were commonly presented as nodules (33.3%) or plaques (27.8%) with a common size of 5-10 cm. Granulomatous reactions were localized to the injection site in 4 cases, distributed on other body areas (remote granuloma) in 11 cases, and associated with lung involvement (systemic granuloma) in 3 cases. Histologically, injection site granuloma showed suppurative reaction in 75% and sarcoidal reaction in 25%. Remote granuloma showed tuberculoid reaction in 27.3%, interstitial in 27.3%, and sarcoidal in 45.4%. Systemic granuloma showed sarcoidal reaction in all cases. After withdrawal of IFN, only 3 lesions showed spontaneous complete clearance, whereas most of the lesions (83.3%) showed only partial improvement. Our results suggested that IFN is not a causal agent of all associated cutaneous granulomas but it mostly provokes the appearance of granulomatous reactions in susceptible individuals. Findings that prove this concept include the formation of granuloma in body sites away from the injection site, the heterogeneous pattern of granuloma both clinically and histologically, and incomplete clearance of most of the lesions after withdrawal of IFN.

Progress in the understanding and utilization of biologic response modifiers in the treatment of uveitis

Uveitis is the third most common cause of blindness in developed countries. Considering the systemic and local complications of long-term corticosteroid therapy and the intolerance due to side effects and ineffectiveness of conventional chemotherapy, use of biologic response modifiers is a reasonable alternative in the treatment of non-infectious uveitis and persistent uveitic macular edema. The majority of the evidence presented here comes from open uncontrolled analyses. Based on these studies, tumor necrosis factor alpha inhibitors, especially infliximab and adalimumab, have been shown to be effective in the treatment of non-infectious uveitis in numerous studies. More research is necessary, particularly multi-center randomized clinical trials, to address the choice of biologic response modifier agent and the length of treatment as we employ biologic response modifiers in different types of uveitis and persistent uveitic macular edema.

Worsening of pulmonary sarcoidosis

PURPOSE OF REVIEW

Despite the frequent occurrence of worsening pulmonary symptoms in pulmonary sarcoidosis patients, there is little available information concerning this topic.

RECENT FINDINGS

In this review, we outline the various causes for these symptoms. We propose to partition the various causes for these symptoms into specific categories.

SUMMARY

We believe that these categories will provide the clinician a framework to evaluate pulmonary sarcoidosis patients with such symptoms in a rigorous way that may be useful in optimizing their care.

The role of type I interferons and other cytokines in dermatomyositis

Much work has been done to unveil the mechanisms behind the pathogenesis of dermatomyositis (DM) - mainly those involving certain pathogenic cytokines, termed "pathokines" as the principal cytokines involved. Recently, it has become clear that a group of cytokines known as type I interferons (IFN-Is) play a significant role in the development of DM. We review the literature published between 1946 and 2014 using an Ovid Medline database search to provide an update on the role of IFN-Is and other cytokines in the pathogenesis of DM. We provide information about the genes and proteins induced by IFN-Is and potential mechanisms by which these downstream products relate to clinical disease activity. We also explore findings of other autoimmune phenomena that may contribute to disease onset and activity including T-helper 17 (Th17) cells and associated interleukins, as well as autoantibodies. Finally, we provide a brief update on current treatment options for DM as well as some new immunomodulatory treatment modalities in development.

Comparison of molecular signatures from multiple skin diseases identifies mechanisms of immunopathogenesis

The ability to obtain gene expression profiles from human disease specimens provides an opportunity to identify relevant gene pathways, but is limited by the absence of data sets spanning a broad range of conditions. Here, we analyzed publicly available microarray data from 16 diverse skin conditions in order to gain insight into disease pathogenesis. Unsupervised hierarchical clustering separated samples by disease and common cellular and molecular pathways. Disease specific signatures were leveraged to build a multi-disease classifier which predicted the diagnosis of publicly and prospectively collected expression profiles with 93% accuracy. In one sample, the molecular classifier differed from the initial clinical diagnosis and correctly predicted the eventual diagnosis as the clinical presentation evolved. Finally, integration of interferon (IFN) regulated gene programs with the skin database revealed a significant inverse correlation between IFN–β and IFN–γ programs across all conditions. Our study provides an integrative approach to the study of gene signatures from multiple skin conditions, elucidating mechanisms of disease pathogenesis. Additionally, these studies provide a framework for developing tools for personalized medicine towards the precise prediction, prevention, and treatment of disease on an individual level.

Interferon-alpha-induced sarcoidosis in a patient being treated for hepatitis C

PATIENT

Female, 43 FINAL DIAGNOSIS: -

SYMPTOMS

Diarrhea • generalized weakness • headache • lightheadedness • nausea • rash • short of breath • vomiting

MEDICATION

- Clinical Procedure: - Specialty: Pulmonology.

OBJECTIVE

Rare diseae.

BACKGROUND

IFN-alpha-2b in combination with ribavirin is now the standard of care for the treatment of hepatitis C. Sarcoidosis is a chronic multisystem granulomatous disorder characterized by noncaseating granulomas in the involved organs. The pathologic hallmark of sarcoidosis is the presence of noncaseating granulomas in the interstitium that typically involve the lymphatics.

CASE REPORT

A 43-year-old woman presented to our care with 2-week history of nausea, vomiting, diarrhea, shortness of breath, migraine headache, maculopapular rash, generalized weakness, and lightheadedness. She had been treated for hepatitis C with telaprevir, ribavirin, and interferon-alpha-2b for 6 months. Chest radiograph showed bilateral diffuse prominence of bronchovascular markings. CT of the chest revealed bilateral diffuse centrilobular nodules with associated intralobular septal thickening, thickening of the central peribronchovascular interstitium, nodularity of the major fissures, and mediastinal lymphadenopathy. These findings were suspicious for atypical pulmonary sarcoidosis, possibly interferon-induced. The pathology of the mediastinal lymph node biopsy revealed noncaseating granulomatous inflammation consistent with the diagnosis of pulmonary sarcoidosis. Pathology of the skin punch biopsy showed giant-cell granulomatous inflammation without necrosis. The patient was started on prednisone 40 mg daily with a steroid tapering course for 8 weeks.

CONCLUSIONS

The management of IFN-induced sarcoidosis includes the discontinuation of IFN therapy with or without the administration of systemic corticosteroids. With the increasing prevalence of HCV in the United States, it is likely that more IFN-alpha-induced sarcoidosis will be encountered by clinicians.

Update on the use of systemic biologic agents in the treatment of noninfectious uveitis

Uveitis is one of the leading causes of blindness worldwide. Noninfectious uveitis may be associated with other systemic conditions, such as human leukocyte antigen B27-related spondyloarthropathies, inflammatory bowel disease, juvenile idiopathic arthritis, Behçet’s disease, and sarcoidosis. Conventional therapy with corticosteroids and immunosuppressive agents (such as methotrexate, azathioprine, mycophenolate mofetil, and cyclosporine) may not be sufficient to control ocular inflammation or prevent non-ophthalmic complications in refractory patients. Off-label use of biologic response modifiers has been studied as primary and secondary therapeutic agents. They are very useful when conventional immunosuppressive therapy has failed or has been poorly tolerated, or to treat concomitant ophthalmic and systemic inflammation that might benefit from these medications. Biologic therapy, primarily infliximab, and adalimumab, have been shown to be rapidly effective for the treatment of various subtypes of refractory uveitis and retinal vasculitis, especially Behçet’s disease-related eye conditions and the uveitis associated with juvenile idiopathic arthritis. Other agents such as golimumab, abatacept, canakinumab, gevokizumab, tocilizumab, and alemtuzumab may have great future promise for the treatment of uveitis. It has been shown that with proper monitoring, biologic therapy can significantly improve quality of life in patients with uveitis, particularly those with concurrent systemic symptoms. However, given high cost as well as the limited long-term safety data, we do not routinely recommend biologics as first-line therapy for noninfectious uveitis in most patients. These agents should be used with caution by experienced clinicians. The present work aims to provide a broad and updated review of the current and in-development systemic biologic agents for the treatment of noninfectious uveitis.

Cutaneous and pulmonary sarcoidosis following treatment of multiple sclerosis with interferon-β-1b: a case report

INTRODUCTION

Several cases of sarcoidosis following treatment with interferon-α have been reported in the literature, but those following interferon-β are very rare. We report the case of a patient with multiple sclerosis who developed pulmonary and cutaneous sarcoidosis following treatment with Betaseron® (interferon-β-1b).

CASE PRESENTATION

A 33-year-old Caucasian woman with a history of multiple sclerosis, treated with interferon-β-1b for 2.5 years developed erythema nodosum in her lower limbs, a breast abscess, and unilateral adenopathy of her left lung. A skin biopsy confirmed sarcoidosis. After the discontinuation of interferon-β-1b and treatment with indomethacin and prednisolone, she recovered.

CONCLUSIONS

Sarcoidosis is considered one of the most common multiple sclerosis imitators with involvement of the central nervous system. However, although rare, sarcoidosis can develop following treatment with interferon-β-1b and should be considered in patients with multiple sclerosis treated with beta-interferons who develop pulmonary or extra-pulmonary manifestations of sarcoidosis. Interferon-β-1b discontinuation is the first and most important step in the treatment of such cases followed by treatment with corticosteroids.

Two cases of interferon-alpha-induced sarcoidosis Koebnerized along venous drainage lines: new pathogenic insights and review of the literature of interferon-induced sarcoidosis

Sarcoidosis is a systemic granulomatous disorder of unknown origin commonly affecting the lung, the lymphoid system and the skin. We report here two cases of cutaneous sarcoidosis in two former intravenous drug users following interferon (IFN)-α and ribavirin therapy for chronic hepatitis C. Both patients developed skin sarcoidosis along venous drainage lines of both forearms, coinciding with the areas of prior drug injections. The unique distribution of the skin lesions suggests that tissue damage induced by repeated percutaneous drug injections represents a trigger for the local skin manifestation of sarcoidosis. Interestingly, skin damage was recently found to induce the local expression IFN-α, a well-known trigger of sarcoidosis in predisposed individuals. Here we review the literature on sarcoidosis elicited in the context of IFN-α therapy and propose a new link between the endogenous expression of IFN-α and the induction of disease manifestations in injured skin.

Acute pulmonary exacerbations of sarcoidosis

Exacerbations of sarcoidosis are common. In particular, exacerbations of pulmonary sarcoidosis are reported in more than one-third of patients. Despite their frequent occurrence, there is little medical evidence concerning the definition, diagnosis, and treatment of pulmonary exacerbations of sarcoidosis. In this article, we propose a definition of acute pulmonary exacerbations of sarcoidosis (APES). We review the meager medical literature concerning the risk factors, diagnosis, and treatment of this condition. Given the limited information concerning APES, we acknowledge that this article is not a definitive resource but, rather, a position paper that will encourage greater consideration of the pathogenesis, diagnostic challenges, and treatment approaches to this condition. We believe that further focus on APES will improve the quality of care of patients with pulmonary sarcoidosis.

Sarcoidosis triggered by interferon-Beta treatment of multiple sclerosis: a case report and focused literature review

OBJECTIVES

To report a rare case of sarcoidosis induced by chronic interferon-beta (a type I interferon) therapy of multiple sclerosis and to review previously reported cases.

METHODS

We describe a patient with a prior diagnosis of multiple sclerosis, who developed noncaseating granulomas in her skin and pulmonary lymph nodes, consistent with sarcoidosis, while being treated with recombinant interferon-beta. A retrospective review of the literature was performed using the PubMed database.

RESULTS

In our patient, sarcoidosis developed after 3 years of continuous recombinant interferon-beta therapy, dosed 3 times a week. The patient presented with progressive dyspnea on exertion, diffuse arthralgias, low-grade fevers, with an acute onset of rash. The diagnosis of sarcoidosis was secured by finding typical, well-formed, noncaseating granulomas on skin and endobronchial biopsies, with other possible etiologies for granulomatous conditions excluded beforehand. Following the withdrawal of recombinant interferon-beta and a course of corticosteroids combined with disease-modifying anti-rheumatic drug therapy, the patient's clinical presentation resolved. Excluding ours, only 4 additional cases of sarcoidosis developing after interferon-beta therapy have been reported, with 2 of those cases in the context of underlying multiple sclerosis.

CONCLUSIONS

Developing sarcoidosis during treatment of multiple sclerosis with recombinant interferon-beta represents an exceedingly rare and paradoxical adverse event. The occurrence of sarcoidosis with the use of this agent is perhaps due to a dysregulation in the modulatory role played by interferon-beta (and more generally type I interferon) expression in chronic inflammation.

Interferon-induced sarcoidosis

Sarcoidosis is a rare side effect of interferon therapy that has been reported over the last years. We present the case of a 43-year-old man presenting with systemic sarcoidosis during treatment with pegylated interferon and ribavirin. Skin lesions, which were found to be associated with asymptomatic bilateral hilar lymph nodes and pulmonary nodules, were the sole clinical manifestation of the disease. Stopping therapy resulted in clinical and radiological improvement.

Development of sarcoidosis following completion of treatment for hepatitis C with pegylated interferon-{alpha}2a and ribavirin: a case report and literature review

Sarcoidosis is a chronic inflammatory multisystem disease of unknown etiology. We report on a woman, aged 57 years, presenting with typical sarcoidosis occurring two months after completion of a six-month course of interferon-α and ribavirin for chronic hepatitis C virus infection. The current observation is interesting with regard to the time elapsed between the occurrence of symptoms and antiviral treatment withdrawal, and spontaneous recovery after ten months of follow-up. Pathophysiological mechanisms involved in the development of antiviral therapy-induced sarcoidosis are discussed.

The expression of STAT-1 and phosphorylated STAT-1 in conjunctival granulomas

PURPOSE

Sarcoidosis is a granulomatous inflammatory disease whose cause is unknown. Based on gene expression profiles of peripheral blood and on immunostaining of lymph nodes from sarcoidosis patients, the authors recently implicated the transcription factor STAT-1 in the pathogenesis. They explored the potential contribution of STAT-1 in an ocular manifestation of this disease.

METHODS

Conjunctival biopsies from 4 subjects with known sarcoidosis and from 8 subjects with conjunctival granulomas presumed from causes other than sarcoidosis were immunostained for STAT1.

RESULTS

STAT-1 was readily detectable in all biopsies from patients with sarcoidosis and in 3 controls. The activated form of STAT-1, phosphorylated STAT-1, was also more frequently detected in tissue from subjects with sarcoidosis relative to controls.

CONCLUSIONS

The activities of STAT-1 in regulating the inflammatory response suggest that it contributes to the conjunctival granulomas characteristic of sarcoidosis, but its expression is not specific for either sarcoidosis or all granulomatous conjunctival disease.

Diagnosis and management of interstitial pneumonitis associated with interferon therapy for chronic hepatitis C

Interstitial pneumonitis (IP) is an uncommon pulmonary complication associated with interferon (IFN) therapy for chronic hepatitis C virus (HCV) infection. Pneumonitis can occur at any stage of HCV treatment, ranging from 2 to 48 wk, usually in the first 12 wk. Its most common symptoms are dyspnoea, dry cough, fever, fatigue, arthralgia or myalgia, and anorexia, which are reversible in most cases after cessation of IFN therapy with a mean subsequent recovery time of 7.5 wk. Bronchoalveolar lavage in combination with chest high resolution computed tomography has a high diagnostic value. Prompt discontinuation of medication is the cornerstone, and corticosteroid therapy may not be essential for patients with mild-moderate pulmonary functional impairment. The severity of pulmonary injury is associated with the rapid development of IP. We suggest that methylprednisolone pulse therapy followed by low dose prednisolone for a short term is necessary to minimize the risk of fatal pulmonary damage if signs of significant pulmonary toxicity occur in earlier stage. Clinicians should be aware of the potential pulmonary complication related to the drug, so that an early and opportune diagnosis can be made.

Cutaneous sarcoidosis: updates in the pathogenesis

Sarcoidosis is a multiorgan granulomatous disease in which the skin is one of the frequently involved target organs. Cutaneous involvement occurs in a third of patients with sarcoidosis and has protean manifestations. More than a century has passed since the initial description of sarcoidosis, but its cause continues to be an enigma. Recent studies have introduced several new insights into the pathogenesis of this disease. The aim of this literature review was to provide a comprehensive overview on the current updates in the pathogenesis of sarcoidosis. This review has revealed that several genetic polymorphisms are associated with an increased risk of developing sarcoidosis, suggesting that genetic susceptibility to sarcoidosis is probably polygenic. Environmental factors may also modify the susceptibility to sarcoidosis. Evidence favouring an infectious aetiology has been accumulating, but the results of studies are conflicting. The current concept is that the pathogenesis of sarcoidosis involves a T-helper-1-mediated immune response to environmental antigens in a genetically susceptible host. The studies carried out on sarcoidosis have largely focused on the pulmonary aspects and have been mainly conducted by respiratory physicians. In contrast, research conducted on the cutaneous aspects of sarcoidosis is comparatively limited. Although tremendous advances have been made, there is a significant gap between the vast knowledge accumulated on sarcoidosis in recent years and the understanding of this disease.

Type I IFNs and their role in the development of autoimmune diseases

BACKGROUND

Since their initial use in the 1980s, IFNs have become an essential component of the therapy for many diseases such as hepatitis and multiple sclerosis. Although they have been extremely useful in conditions that pose therapeutic challenges, complications associated with their use have been widely reported including emerging reports of several autoimmune diseases. Many of these reports have shed light on the pathogenesis of autoimmune disorders and helped to highlight not only the critical role of type I IFNs in defense against viral infections but also the pivotal role they occupy in the interface between innate and adaptive immunity. Many patients with autoimmune disease have increased responsiveness to type I IFNs (alpha/beta), and therapy with these cytokines has induced or unmasked autoimmune disease in many additional patients.

OBJECTIVE

The objective of this paper is to discuss the role of type I IFNs in autoimmunity.

METHODS

The literature regarding type I IFNs and autoimmunity was reviewed using the Medline database from 1950 to 2009. Search terms included 'interferon alpha' and 'autoimmune disease' and 'interferon beta' and 'autoimmune disease'. Case reports, case series, reviews and prospective studies were included in the analysis.

RESULTS/CONCLUSIONS

In the literature a variety of autoimmune disorders have reportedly been induced by the use of type I IFNs, being used, although these are primarily in the form of case reports and case series. Nevertheless, there is a growing body of molecular evidence to support the clinical association. The role of IFNs in the induction of autoimmunity is complex with interplay of many genetic and environmental factors that influence the balance between normal and aberrant immune responsiveness, ultimately leading to the observed clinical manifestations.

Hypothesis: sarcoidosis is a STAT1-mediated disease

Immunologic pathways involved in sarcoidosis pathogenesis are largely unknown. We hypothesized that patients with sarcoidosis have characteristic mRNA profiles. Microarray analysis of gene expression was done on peripheral blood (12 patients, 12 controls), lung (6 patients, 6 controls) and lymph node (8 patients, 5 controls). Comparing peripheral blood from patients with sarcoidosis to controls, 872 transcripts were upregulated and 1039 were downregulated at >1.5-fold change and a significant q value. Several transcripts associated with interferon and STAT1 were upregulated. Lung and lymph node analyses also showed dramatic increases in STAT1 and STAT1-regulated chemokines. Granulomas in lymph nodes of patients with sarcoidosis expressed abundant STAT1 and phosphorylated STAT1. STAT1 might play an important role in sarcoidosis. This novel hypothesis unites seemingly disparate observations with regard to sarcoidosis including implication of a casual role for interferons, a suspected infectious trigger, T(H)1 predominating lymphocytes in bronchoalveolar lavage, and the association with hypercalcemia.

Dendritic cells in the pathogenesis of sarcoidosis

Sarcoidosis is a noncaseating granulomatous disease, likely of autoimmune etiology, that causes inflammation and tissue damage in multiple organs, most commonly the lung, but also skin, and lymph nodes. Reduced dendritic cell (DC) function in sarcoidosis peripheral blood compared with peripheral blood from control subjects suggests that blunted end organ cellular immunity may contribute to sarcoidosis pathogenesis. Successful treatment of sarcoidosis with tumor necrosis factor (TNF) inhibitors, which modulate DC maturation and migration, has also been reported. Together, these observations suggest that DCs may be important mediators of sarcoidosis immunology. This review focuses on the phenotype and function of DCs in the lung, skin, blood, and lymph node of patients with sarcoidosis. We conclude that DCs in end organs are phenotypically and functionally immature (anergic), while DCs in the lymph node are mature and polarize pathogenic Th1 T cells. The success of TNF inhibitors is thus likely secondary to inhibition of DC-mediated Th1 polarization in the lymph node.

Interferon-alpha-associated presumed ocular sarcoidosis

BACKGROUND

Interferon alpha, used in the treatment of different viral, autoimmune and malignant diseases, is known to induce a variety of side effects. Recently, induction of sarcoidosis during interferon therapy has been reported. We analyzed patients for uveitis, possibly induced by interferon alpha.

METHODS

We report on three patients who had developed typical signs of ocular sarcoidosis under treatment with interferon alpha for chronic hepatitis C virus infection. In two patients, conventional interferon alpha was used and in another one, pegylated interferon alpha-2b. All patients additionally received ribavirin.

RESULTS

In all three cases, panuveitis was diagnosed. The mean duration of interferon treatment before development of uveitis was 10 months. Clinically, all patients demonstrated granulomatous panuveitis with choroidal granulomas of various sizes. In one case, the uveitis developed together with renal failure, fever and malaise. In this patient, an elevated ACE level was detected. In another patient, the diagnosis of sarcoid induced uveitis was confirmed by positive chest CT scan. The intraocular inflammation was managed with a reduction of the interferon dosage. The therapy with ribavirin was not changed. All patients received topical steroids. Systemic steroids were applied only in the case with systemic disease manifestations.

CONCLUSIONS

Uveitis can be a sign of sarcoidosis induced by interferon alpha. Further studies are required to support the observation that with early diagnosis the prognosis of uveitis seems to be good.

Drug-induced arthritic and connective tissue disorders

OBJECTIVES

All pharmacologic agents have the potential for both benefit and toxicity. Among the more interesting and important adverse consequences of drug therapy are a range of joint and connective tissue complaints that may mimic or reproduce primary rheumatologic diseases. In this article, we review the literature on commonly used drugs reported to induce arthritis and/or connective tissue-based diseases. We assess the strength of the reported associations, discuss diagnostic features and treatment implications, and consider possible mechanisms for drug-induced genesis of rheumatic conditions.

METHODS

We reviewed the Medline database from 1987 to 2006 to identify drug-induced arthritic and connective-tissue disease syndromes, utilizing 48 search terms. A qualitative review was performed after the articles were abstracted and the relevant information was organized.

RESULTS

Three hundred fifty-seven articles of possible relevance were identified. Two hundred eleven publications were included in the final analysis (case series and reports, clinical trials, and reviews). Many drugs were identified as mimicking existing rheumatic conditions, including both well-established small molecules (eg, sulfasalazine) and recently introduced biologic agents (eg, antitumor necrosis factor agents). The most commonly reported drug-induced rheumatic conditions were lupus-like syndromes. Arthritis and vasculitis were also often reported.

CONCLUSIONS

Drug-induced rheumatic syndromes are manifold and offer the clinician an opportunity to define an illness that may remit with discontinuation of the offending agent. Early diagnosis and withdrawal of the drug may prevent unnecessary morbidity and disability.

Development of hepatic granulomas in patients receiving pegylated interferon therapy for recurrent hepatitis C virus post liver transplantation

Infrequently, hepatitis C (HCV) appears to be the cause of hepatic granulomas. Interferon therapy for HCV has been increasingly associated with the development of sarcoidosis.

AIMS

We sought to determine the incidence of hepatic granulomas in patients with recurrent HCV post liver transplantation (LT).

METHODS

Between 1994 and 2005, 820 patients were transplanted for HCV at our institution. The pathology database was searched for patients having recurrent HCV and granulomas. At Mount Sinai Medical Center, protocol biopsies have been performed for the last 2 years in patients receiving pegylated interferon-alpha2b and ribavirin (PEG) for recurrent HCV. Review of slides from explanted livers, pre- and post-perfusion biopsies, and all allograft biopsies were evaluated. Lipogranulomas were excluded because of their frequent association with steatosis.

RESULTS

A total of 10,225 liver biopsies were performed on HCV patients, and 25 (0.24%) showed non-caseating epithelioid granulomas. Hepatic granulomas were detected in 14 post-LT HCV patients; 9 patients received PEG. Typically, only 1 lobular granuloma was found. None of these patients had granulomas in the native liver or in any biopsy before interferon therapy; 6/9 patients had undetectable HCV-RNA levels, and 4 had sustained viral response. No other cause for granuloma formation was identified in the 6 patients.

CONCLUSIONS

Hepatic granulomas are infrequently found in HCV liver biopsies and rarely found in post-LT biopsies with recurrent HCV. When present, they occur more commonly in patients receiving and virologically responding to PEG therapy. The presence of granulomas in patients with HCV being treated with PEG may not warrant an extensive etiologic work-up for granulomatous hepatitis unless otherwise clinically indicated.

Safety and tolerability of sequential pegylated IFN-alpha2a and tenofovir for hepatitis B infection in HIV(+) individuals

Chronic hepatitis B virus infections are a major cause of morbidity and mortality in HIV co-infected patients. The standard of care for treating HCV co-infection has been guided by major clinical trials, but the treatment of HBV co-infection has not been as thoroughly studied and the standard of care remains largely untested. The single pill formulation of tenofovir with emtricitabine has become a standard treatment approach in HBV co-infected patients. WU114 was a phase 1 clinical trial that examined the safety and tolerability of sequential treatment of HBV with pegylated interferon-alpha2a plus delayed-initiation tenofovir in HIV co-infected individuals. We postulated that initial HBV viral load reduction with pegylated interferon prior to initiation of nucleoside/nucleotide therapy would increase seroconversion events and durability of HBV virologic suppression. No severe pegylated IFN-alpha2a drug toxicities were seen in either the monotherapy or delayed tenofovir arms. Sequential pegylated interferon and tenofovir-based therapy was tolerable and should be compared with dual nucleoside/nucleotide suppression to determine relative frequencies of seroconversion and durability of HBV suppression in co-infected patients.

Syndromes and complications of interferon therapy

PURPOSE OF REVIEW

Interferons are used to treat a variety of medical conditions. They are integral players in immunity and a number of immune-mediated complications can arise during interferon therapy. We have reviewed the occurrence of these complications, and the mechanisms behind them.

RECENT FINDINGS

Case reports and follow-up studies of large cohorts of patients on interferon therapy have confirmed that immune-mediated complications are uncommon but can occur in a number of different organ systems. IFNalpha production is induced by specific autoantibody-nuclear antigen immune complexes, and has a key role in the development and maintenance of autoimmunity in systemic lupus erythematosus.

SUMMARY

Interferon therapy can precipitate immune-mediated abnormalities de novo or can exacerbate an existing autoimmune tendency. This is manifest in the rise in titre of existing antibodies and in the development of clinical disease in patients with preexisting antibodies. Type I interferons have a key role in the development of systemic lupus erythematosus.