The linkage between Churg-Strauss syndrome and leukotriene receptor antagonists: fact or fiction?

Kidney Failure in Pauci-immune Crescentic Glomerulonephritis: Rationale for Immunosuppression to Improve Kidney Outcome

PURPOSE OF REVIEW

Pauci-immune crescentic glomerulonephritis is the hallmark finding in ANCA-associated vasculitis (AAV) when the kidneys are affected. The rationale for immunosuppression in AAV is based on the underlying autoimmune nature of the disease. Overall remission rates, kidney outcomes, and the burden of disease have greatly improved since the discovery of various immunosuppressive therapies, but relapses remain common, and a significant proportion of patients continue to progress to end-stage kidney disease. Here, we review the role of immunosuppressive therapies for the treatment of pauci-immune crescentic glomerulonephritis.

RECENT FINDINGS

Besides the recognized role of B and T cells in the pathogenies of AAV, the focus on the contribution of inflammatory cytokines, neutrophil extracellular traps (NETs), and the complement system allowed the discovery of new therapies. Specifically, the C5a receptor blocker (avacopan) has been approved as a glucocorticoid-sparing agent. Additionally, based on observational data, more clinicians are now using combination therapies during the induction phase. There is also an evolving understanding of the role of plasma exchange in removing ANCA antibodies. Furthermore, the recent development of risk score systems provides physicians with valuable prognostic information that can influence decisions on immunosuppression, although future validation from larger cohorts is needed. The over-activation of various immune pathways plays a significant role in the pathogenesis of pauci-immune crescentic glomerulonephritis in AAV. Immunosuppression is, therefore, an important strategy to halt disease progression and improve overall outcomes. Relapse prevention while minimizing adverse events of immunosuppression is a major long-term goal in AAV management.

When inflammation is not just inflammation-A review of systemic diseases of the nose and sinuses part 2: Granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis

BACKGROUND

Chronic rhinosinusitis is a very common condition. Granulomatosis with polyangiitis (GPA) and eosinophilic granulomatosis with polyangiitis (eGPA) are systemic diseases which can contribute to the development of chronic rhinosinusitis in select patients.

OBJECTIVE

Characterize the presenting features, diagnostic criteria, workup, and management of granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis as they are encountered in otolaryngology clinics.

METHODS

Full length manuscripts published 2000 or later were reviewed. A separate search was conducted for each disease. Pertinent clinical features related to sinonasal manifestations of GPA and eGPA were collected and reported in this review.

RESULTS

467 references were discovered during literature review process. In total, 42 references for GPA and 35 references for eGPA were included in this review.

CONCLUSION

GPA and eGPA are vasculitis syndromes which commonly present in the context of multisystem disease. For GPA, pulmonary and renal disease are common; for eGPA a history of asthma is nearly ubiquitous. Sinonasal disease is a very common feature for both disease processes and may precede the development of systemic symptoms in many patients. Clinical work up and diagnosis is complex and generally requires multidisciplinary care. Treatment primarily consists of immunosuppressive agents, and a number of steroids, steroid sparing agents, and biologics have been shown to be effective. The role of sinus surgery includes tissue biopsy for diagnosis, functional surgery for symptom management in select cases, and reconstruction of cosmetic and functional defects.

Is Leukotriene Receptor Antagonist the Direct Cause of Churg-Strauss Syndrome in Asthmatic Patients?

One of the main reasons for continuous, persistent asthma is when there is a change in the structure of the airways and the Lung parenchyma. These persistent changes bring a much worse prognosis to asthmatic conditions and predispose the situation to severe asthmatic syndromes such as Churg-Strauss syndrome (CSS). CSS is an inflammation of systemic blood vessels and is a rare disorder that can be suspected in long-standing asthmatic patients. Leukotriene antagonists receptor antagonists (LTRA) have been used to treat asthma along with tapering steroids. But after the introduction of LTRA therapy in these patients suggests a causal relation between LTRA initiation and the development of CSS, or it is an unmasking of CSS as the dose of steroid tapers down with LTRA therapy. This review highlights the relationship between leukotriene antagonists and the pathogenesis of CSS. It summarizes the current literature regarding the development of CSS with the initiation of LTRA therapy on asthmatic patients. The literature on this topic was reviewed using different research/article searches, manual library searches, conference abstracts, and internet searches.

A worldwide pharmacoepidemiological update of drug-associated ANCA-associated vasculitis at the time of targeted therapies

OBJECTIVE

The literature data supporting the role of a drug in the onset of drug-associated anti-neutrophil cytoplasmic antibody-associated vasculitis (DA-AAV) mainly rely on case reports or short series and implicate old treatments. The advent of new treatments may have modified the epidemiology of these adverse drug reactions (ADRs). We therefore aimed to update this list by using a pharmacovigilance-based data mining approach.

METHODS

We collected data on ADRs reported with the MedDRA preferred term "Anti-neutrophil cytoplasmic antibody positive vasculitis" up to November 2020 from the World Health Organization pharmacovigilance database (VigiBase^® ). For each retrieved drug, a case/noncase analysis was performed, and disproportionate reporting was calculated by using the information component (IC). A positive IC₀₂₅ value, which is the lower end of the 95% credibility interval, was considered significant.

RESULTS

A total of 483 deduplicated individual case safety reports of DA-AAV involving 15 drugs with an IC₀₂₅ >0 were retrieved. DA-AAV occurred in 264 (71.2%, n=371) women, the median age at onset was 62 years [45-72], and the median time to onset between the introduction of the suspected drug and DA-AAV was 9 months [1-36]. DA-AAV occurrence was considered serious in 472 (97.7%, n=481) cases and fatal in 43 (8.9%) cases. The drugs associated with the highest disproportionate reporting were hydralazine, propylthiouracil, thiamazole, sofosbuvir, minocycline, carbimazole, mirabegron, and nintedanib.

CONCLUSION

This study strengthens the previously suspected association but also identifies 3 new drugs that may cause DA-AAV. Particular attention should be given to these drugs by prescribers and in experimental studies.

Peripheral neuropathy in systemic vasculitis and other autoimmune diseases - a report of five cases emphasizing the importance of etiologic characterization

Introduction

Peripheral neuropathies may present in the context of systemic vasculitis and other autoimmune diseases. The etiologic characterization is crucial to define the treatment and prognosis in secondary vasculitis. The purpose of this study is to describe the pathway of etiologic investigation including the role of nerve biopsy.

Methods

Retrospective analysis of patients seen in the neuromuscular outpatient clinic during the last four years with peripheral neuropathy in the context of systemic vasculitis or other autoimmune diseases.

Results

We present five patients with stepwise progressive sensorimotor deficits of upper and lower limbs. All patients presented with systemic features and one of them had an established diagnosis of systemic vasculitis. They underwent an extended blood panel, including autoimmune and serologic tests. Electromyography and nerve conduction studies revealed asymmetric axonal sensorimotor polyneuropathies in four patients, and an axonal sensorimotor multiple mononeuropathy in one. Four patients underwent nerve biopsy and the other performed a skin biopsy, with findings suggestive of possible vasculitic processes. The etiologies identified included microscopic polyangiitis, HBV-related polyarteritis nodosa and two eosinophilic granulomatosis with polyangiitis. In the last patient a specific etiology could not be established.

Conclusion

This series reveals the etiologic and phenotypic diversity of peripheral neuropathies related with systemic vasculitis. The therapeutic approach and prognosis were distinct in each patient, emphasizing the importance of a prompt diagnosis and appropriate treatment.

Cerebral vasculitis

The noninfectious, inflammatory vasculitides include giant cell arteritis, Takayasu disease, Churg-Strauss angiitis, Wegener disease, polyarteritis nodosa, microscopic polyangiitis, Buerger disease, amyloid-β-related angiitis, and isolated vasculitis of the central nervous system. While these disorders are relatively uncommon, they produce a variety of neurologic diseases including muscle disease, mononeuropathy multiplex, polyneuropathy, cranial nerve palsies, visual loss, seizures, an encephalopathy, venous thrombosis, ischemic stroke, and intracranial hemorrhage. The multisystem vasculitides often have stereotypical clinical findings that reflect disease of the kidney, sinuses, lungs, skin, joints, or cardiovascular system. These disorders also usually have abnormalities found on serologic testing. Isolated vasculitis of the central nervous system is more difficult to diagnose because the clinical and brain imaging findings are relatively nonspecific. Examination of the cerebrospinal fluid will demonstrate changes consistent with an inflammatory process. Arteriography often shows areas of segmental narrowing affecting multiple intracranial vessels and brain/meningeal biopsy may be required to establish the diagnosis. Management of patients with a multisystem vasculitis or isolated vasculitis of the central nervous system is centered on the administration of immunosuppressive agents. In many cases, corticosteroids remain the mainstay of medical treatment.

Update on optimal use of omalizumab in management of asthma

Omalizumab is a humanized monoclonal anti-IgE antibody recently approved for the treatment of severe allergic asthma. This drug inhibits allergic responses by binding to serum IgE, thus preventing interaction with cellular IgE receptors. Omalizumab is also capable of downregulating the expression of high affinity IgE receptors on inflammatory cells, as well as the numbers of eosinophils in both blood and induced sputum. The clinical effects of omalizumab include improvements in respiratory symptoms and quality of life, paralleled by a reduction of asthma exacerbations, emergency room visits, and use of systemic corticosteroids and rescue bronchodilators. Omalizumab is relatively well-tolerated, and only rarely induces anaphylactic reactions. Therefore, this drug represents a valid option as add-on therapy for patients with severe persistent allergic asthma inadequately controlled by high doses of standard inhaled treatments.

Churg-Strauss syndrome with severe granulomatous angiitis and crescentic glomerulonephritis, which developed during therapy with a leukotriene receptor antagonist

A 77-year-old Japanese female developed Churg-Strauss syndrome (CSS), showing fever and numbness in bilateral hands. She was being treated for bronchial asthma with combination inhalant of corticosteroid with beta(2)-agonist, and an oral leukotriene receptor antagonist (LTRA), montelukast, for 15 months. She presented fever up to 38°C with microscopic hematuria and proteinuria, serum creatinine level of 0.7 mg/dl, and C-reactive protein of 11 mg/dl. After referral to our hospital, eosinophilia and high myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA) level were observed together with hematuria and proteinuria; renal biopsy examination was performed to clarify the disorder. Renal biopsy specimens showed necrotizing crescent formation, severe granulomatous angiitis in an interlobular artery, and interstitial eosinophilic infiltration. It was noted that nearly intact glomeruli were infiltrated with eosinophils. After treatment with oral prednisolone at initial dose of 40 mg (1 mg/kg body weight), urinary findings rapidly became normal with mild elevation of serum creatinine to 1.5 mg/dl and trace level of serum C-reactive protein in 1 month. Because she was previously treated with montelukast without oral corticosteroid, linkage between CSS and LTRA was highly suspected.

Churg-Strauss angiitis

Churg-Strauss angiitis or syndrome (CSA) is defined as an eosinophil-rich and granulomatous inflammation involving the respiratory tract, and necrotising vasculitis affecting small- to medium-sized vessels, and is associated with asthma and eosinophilia. It is usually classified among the so-called anti-neutrophil antibody (ANCA)-associated systemic vasculitides (AASVs) because of its clinical and pathological features that overlap with those of the other AASVs. However, two recent studies on large cohorts of patients have found that ANCAs, usually P-ANCAs/MPO-ANCAs, were present in only 38% of patients. Moreover, the ANCA status was shown to segregate with clinical phenotype. ANCA-positive patients were significantly more likely to have disease manifestations associated with small-vessel vasculitis, including necrotising glomerulonephritis, mononeuritis and purpura, whereas ANCA-negative cases were significantly more likely to have cardiac and lung involvement. Vasculitis was documented less frequently in histological specimens from ANCA-negative patients in comparison with ANCA-positive ones. These findings have led to postulate the predominance of distinct pathogenetic mechanisms in the two subsets of patients: an ANCA-mediated process in ANCA-positive patients and tissue infiltration by eosinophils with subsequent release of toxic product in ANCA-negative cases. Preliminary results suggest that ANCA-positive and ANCA-negative patients also might have a different genetic background. Corticosteroids remain the cornerstone of the initial treatment of CSA. The addition of cyclophosphamide is indicated in treatment of patients with poor-prognosis factors or in patients without poor-prognosis factors but those that are prone to relapses. The length of the maintenance therapy remains to be established. However, the vast majority of patients require long-term corticosteroids treatment to control asthma.

Omalizumab in the treatment of severe asthma: efficacy and current problems

Omalizumab is a humanized monoclonal anti-IgE antibody recently approved for the treatment of severe allergic asthma. This drug inhibits allergic responses by binding to serum IgE, thus preventing their interactions with cellular IgE receptors. Omalizumab is also capable of downregulating the expression of high-affinity IgE receptors on inflammatory cells, as well as the numbers of eosinophils in both blood and induced sputum. The clinical effects of omalizumab include relevant improvements in respiratory symptoms and quality of life, paralleled by a marked reduction of asthma exacerbations, emergency room visits, and use of systemic corticosteroids and rescue bronchodilators. Omalizumab is relatively well tolerated, and only rarely induces anaphylactic reactions. Therefore, this drug represents a valid option as add-on therapy for patients with severe persistent allergic asthma, inadequately controlled by high doses of standard inhaled treatments.