Can sulfasalazine therapy induce or exacerbate Wegener's granulomatosis?

Serum ANCA as Disease Biomarkers: Clinical Implications Beyond Vasculitis

Usually associated with autoimmune diseases, anti-neutrophil cytoplasmic antibodies are also detected in other conditions, such as infections, malignancies, and after intake of certain drugs. Even if the mechanisms of production and their pathogenic role have not been fully elucidated yet, ANCA are widely recognized as a clinically alarming finding due to their association with various disorders. While ANCA target several autoantigens, proteinase-3, and myeloperoxidase are the ones proved to be most frequently related to chronic inflammation and tissue damage in murine models. Albeit these autoantibodies could be present as an isolated observation without any implications, ANCA are frequently used in clinical practice to guide the diagnosis in a suspect of small vessel vasculitis. Conditions that should prompt the clinician to test ANCA status range from various forms of lung disease to renal or peripheral nervous system impairment. ANCA positivity in the presence of an autoimmune disease, especially rheumatoid arthritis, or connective tissue diseases, is frequently correlated with more clinical complications and treatment inefficacy, even in the absence of signs of vasculitis. For this reason, it has been postulated that ANCA could represent the final expression of an immune dysregulation rather than a pathogenic event responsible for organs damage. Recently, it has also been proposed that ANCA specificity (PR3 or MPO) could possibly define ANCA-associated vasculitides better than clinical phenotype. This review aims at summarizing the latest advancements in the field of ANCA study and clinical interpretation.

A Spotlight on Drug-Induced Vasculitis

PURPOSE OF REVIEW

Drug-induced vasculitis (DIV) is a rare form of vasculitis related to the use of various drugs. DIV primarily affects small to medium size vessels, but it can potentially involve vessels of any size. Differentiating between primary systemic vasculitis and DIV can be challenging; however, it is crucial, so that the offending agent can be discontinued promptly.

RECENT FINDINGS

The clinical phenotype of DIV is protean and depends on the size of the affected vessels. It ranges from arthralgias, to an isolated cutaneous rash, to severe single or multi-organ involvement. While withdrawal of the offending drug is the most important step in management, a significant number of patients require immunosuppressive therapy for varying periods of time. DIV can affect any vascular bed size, leading to protean vasculitic syndromes. Increased awareness among general practitioners, specialty, and subspecialty physicians is crucial for early recognition, and withdrawal of drug for better outcomes.

Drug-induced anti-neutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

In recent years, an increasing number of drugs have been proved to be associated with the induction of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). This article reviews the latest research progress on drug-induced AAV.

DATA SOURCES

We conducted a comprehensive and detailed search of the PubMed database. The search terms mainly included drug-induced, ANCA, and vasculitis.

STUDY SELECTION

We summarized the original articles and reviews on drug-induced AAV in recent years. The extracted information included the definition, epidemiology, associated drugs, pathogenesis, clinical features, diagnosis, treatment, and prognosis of drug-induced AAV. We also focused on the differences between drug-induced AAV and primary vasculitis.

RESULTS

The offending drugs leading to drug-induced AAV are almost from pharmacologic categories and we need to be vigilant when using these drugs. The pathogenesis of drug-induced AAV might be multifactorial. The formation of neutrophil extracellular traps is an important mechanism for the development of drug-induced AAV. The clinical features of drug-induced AAV are similar to those of primary AAV. Understanding the difference between drug-induced AAV and primary AAV is helpful to identify drug-induced AAV. Stopping the offending drug at once after diagnosis may be sufficient for those patients with mild symptoms. Immunosuppressive therapy should only be used in patients with vital organs involvement.

CONCLUSIONS

Patients with drug-induced AAV usually have a good prognosis if they stop using the offending drug immediately. Recent advances in research on AAV are expected to help us better understand the pathogenesis of drug-induced AAV.

Genetic Associations and Environmental Exposures in the Aetiopathogenesis of Anti-Neutrophil Cytoplasmic Antibody- Associated Vasculitis: An Updated Review

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) represents a heterogeneous group of rare diseases characterised by necrotising inflammation of the small blood vessels and the presence of ANCA with specificity for proteinase-3 or myeloperoxidase. Genetic susceptibility along with malignancy, drug exposure, and environmental exposures to infectious agents and silica are involved in disease progression. To date, growing evidence has revealed that ANCA specificity defines homogeneous groups of patients more effectively than clinical diagnosis, since proteinase-3 ANCA and myeloperoxidase-ANCA are linked with different genetic backgrounds and epidemiologies. This review presents current and updated knowledge on the central aetiopathogenic role of genetic associations and environmental exposures in AAV; discusses the main mechanisms of ANCA immunogenesis; and highlights the value of ANCA specificity for future classification criteria.

Hydralazine-induced pauci-immune glomerulonephritis: intriguing case series with misleading diagnoses

Hydralazine has been used since the 1950s for the management of hypertension. Evidence for hydralazine-associated vasculitis dates to pre-ANCA (antineutrophil cytoplasmic antibodies) era. This abstract describes two cases of ANCA-positive pauci-immune glomerulonephritis (GN) in challenging scenarios where diagnosis was misconstrued. A comprehensive literature review was done to understand the pathogenesis of drug-induced pauci-immune GN. We have described key diagnostic features that are helpful in distinguishing idiopathic ANCA vasculitis from drug-induced vasculitis. Additionally, we have also described different treatments meant to provide therapy options with the least side effects.

Bilateral renal ischemia after kyphoplasty and clodronate treatment: a case report

INTRODUCTION

The most common adverse effects associated with bisphosphonates are renal toxicity, acute-phase reactions, gastrointestinal toxicity, osteonecrosis of the jaw, transitory fever and uveitis. We report a unique adverse case of vasculitis induced by clodronate.

CASE PRESENTATION

A 61-year-old Caucasian woman developed bilateral renal ischemia after kyphoplasty and clodronate treatment for lumbar vertebral fracture. Tests revealed a vasculitis due to clodronate treatment. The antithrombotic and immunosuppressive drugs allowed us to reduce the extent of the renal ischemia. In the following months the increased auto-antibodies returned to the healthy physiological range, but the chronic renal failure persisted.

CONCLUSIONS

Drug-induced vasculitis is an inflammation of blood vessels caused by the use of various pharmaceutical agents. The spectrum of drug-induced vasculitis can range from cutaneous rashes to fatal multi-organ involvement. To the best of our knowledge this is the first documented case of drug-induced vasculitis caused by clodronate in the literature. Previously, it was verified that clodronate injection could increase the pro-apoptotic action on immune cells. Further studies are necessary to clarify the role of bisphosphonates on drug-inducing vasculitis.

Propylthiouracil-induced antineutrophil cytoplasmic antibody-associated vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) refers to a group of potentially life-threatening autoimmune diseases. A recent development in this field is the recognition that certain drugs can induce AAV. Among these agents, the drug most often implicated in causing disease is the commonly used antithyroid agent propylthiouracil (PTU). This Review provides an update on PTU-induced AAV. Clinical characteristics of PTU-induced AAV are similar to that of primary AAV, but usually have a milder course and better prognosis, provided early cessation of the disease-causing drug. PTU-induced ANCAs usually react to several components of myeloid granules, which is helpful in differentiating PTU-induced AAV from primary AAV. Early cessation of PTU is crucial in the treatment of PTU-induced AAV. The duration of immunosuppressive therapy might be shorter than in primary AAV, depending on the severity of organ damage, and maintenance therapy is not always necessary.