Clinical study of renal impairment in patients with propylthiouracil-induced small-vessel vasculitis and patients with primary ANCA-associated small-vessel vasculitis

Case report: Propylthiouracil-induced serious side effect: Perinuclear antineutrophil cytoplasmic antibody-associated vasculitis or IgA vasculitis?

INTRODUCTION

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare disease characterized by the inflammation and destruction of small blood vessels and circulating ANCAs. Drugs such as antithyroid drugs (ATDs), especially propylthiouracil (PTU), have been used for the production of ANCAs and cause the development of drug-induced AAV. The pathogenesis of this disease is unclear but could be related to the physiological processes affecting the degradation of neutrophil extracellular traps (NETs). At present, PTU is widely used in patients with Graves' disease (GD) who are preparing for pregnancy and whose condition has not been controlled. Once drug-induced AAV has occurred with important organ damage, considering NETs have a significant role in the immune system, whether the cessation of drugs could stop the progression of organ damage is unclear, and a consensus regarding standard treatment has not been established.

PATIENT CONCERNS

In this case report, a female patient who planned pregnancy was hospitalized with multiple joint pain, impaired renal function, and hematuria. Immunofluorescence of the renal biopsy demonstrated spherical and diffuse mesangial distribution of IgA (3+). Autoimmune serology demonstrated positivity for autoantibodies against p-ANCA and an anti-MPO titer 74.72 RU/mL.

DIAGNOSIS

She was diagnosed with PTU-induced p-ANCA-associated and IgA-associated vasculitis (IgAV).

INTERVENTIONS

The patient accepted low doses of glucocorticoid, immunosuppressive therapy and RAI treatment.

OUTCOMES

Both her kidney function and thyroid function remained were on the mend.

CONCLUSION

The authors believe that this type of patient needs to fully consider their pregnancy preparation needs, suspend pregnancy when a small chance of GD remission is indicated, and avoid the use of drugs with reproductive toxicity and other serious adverse events. The multidisciplinary combination therapy of low-dose glucocorticoids and immunosuppressants combined with iodine radiotherapy is one reasonable scheme. At the same time, it is necessary to eliminate the organ damage caused by other reasons. This report provides a clinical treatment basis for patients with drug-induced vasculitis manifestations who cannot receive an accurate diagnosis.

Late Onset of Rivaroxaban-Associated Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis

Although anti-thyroid drugs (ATDs) are the most common cause of drug-associated anti-neutrophil cytoplasmic antibody (ANCA) vasculitis (AAV), many other classes of drugs can lead to drug-associated AAV. We present a unique case of rivaroxaban-associated AAV. A 76-year-old female with a past medical history of atrial fibrillation on rivaroxaban presented with fatigue, bilateral lower extremity purpura, and hemoptysis to an outside hospital. Investigations revealed a positive cytoplasmic-ANCA (c-ANCA) titer of 1:320 and a positive anti-myeloperoxidase (anti-MPO), and negative perinuclear-ANCA (p-ANCA) and anti-proteinase 3 (anti-PR3). In addition, chest imaging demonstrated bilateral ground-glass opacities which raised suspicion for diffuse alveolar hemorrhage (DAH). A lung biopsy revealed acute and ongoing DAH with focally active capillaritis and characteristic pathological findings, which strongly suggested that was likely secondary to rivaroxaban. Rivaroxaban was discontinued, and the patient received pulses of intravenous glucocorticosteroids and rituximab. Her symptoms improved. She continued immunosuppressive therapy with rituximab for 2 years. She presented to our hospital for a second opinion regarding the discontinuation of rituximab, and we decided to discontinue rituximab. After discontinuation, the patient remained stable after 1.5 years of follow-up and did not have any relapses. This is a unique case of rivaroxaban-associated AAV. Clinicians should consider drug-associated AAV in all patients who present with an atypical clinical presentation and/or pathological findings of AAV. Given the broad and rapidly increasing use of novel anticoagulants, it is important to raise awareness of this potential complication. Prompt discontinuation of the drug and initiation of immunosuppressant treatment in severe cases may be lifesaving.

Neutrophil Extracellular Traps (NETs) and Vasculitis

Background: Neutrophil extracellular traps (NETs) have been implicated in host immune responses. Attempts have been made to examine how NETs affect the pathogenesis of complications such as autoimmune and vascular disorders. Aim: This study aimed to explore the relationship between NETs and vasculitis. Material and Methods: The current study entailed the searching of PsycINFO, PubMed, Web of Science, and CINAHL for articles related to the research topic. The search terms and phrases included "vasculitis," "NETs," "neutrophil extracellular traps," "NETosis," and "pathogenesis." The search was limited to articles published between 2009 and 2019. Results: Researchers have shown that NETs contribute to the pathogenesis of vasculitis through different mechanisms and processes, including renal failure and vascular damage. The protective effects of NETs have also been highlighted. Discussion: Overall, some scholars have shown the effectiveness of using DNase I and the PAD4 inhibitor Cl-amidine to treat vasculitis by restricting NET formation. However, observations have been noted in only animal experimental models. Conclusion: Neutrophil hyperactivity and its role in vasculitis are not yet fully understood. More studies aiming to determine the accurate function of NETs in vasculitis pathogenesis, particularly in humans, should be undertaken. Intensive research on NETs and vasculitis can increase the knowledge of medical practitioners and contribute to the development of new treatment methods to enhance patient outcomes in the future.

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.

The Phenomenon of Neutrophil Extracellular Traps in Vascular Diseases

Vascular diseases constitute a global health issue due to the increasing number of cases of patients with these diseases. The pathogenesis of the majority of these diseases, including atherosclerosis and thrombosis, is complex and not yet fully understood. One of the major causes for their occurrence can be immune disorders resulting in the development of a chronic inflammation within the vessels. In recent years, studies have placed emphasis on the role of neutrophils in the development of these diseases, i.e., the discovery of neutrophil extracellular traps (NETs) demonstrated that the structures released by the cells may contribute to the enhancement of inflammatory reactions and cell damage. This article summarizes current knowledge on the role of NETs during atherosclerosis, thrombosis and small-vessel vasculitis, especially in antineutrophil cytoplasmic antibody (ANCA)-associated small-vessel vasculitis (AAV).

Drug-induced nephropathies

Drugs are associated frequently with the development of various types of acute and chronic kidney diseases. Nephrotoxicity is associated most commonly with injury in the tubulointerstitial compartment manifested as either acute tubular injury or acute interstitial nephritis. A growing number of reports has also highlighted the potential for drug-induced glomerular disease, including direct cellular injury and immune-mediated injury. Recognition of drug-induced nephropathies and rapid discontinuation of the offending agents are critical to maximizing the likelihood of renal function recovery. This review will focus on the pathology and pathogenesis of drug-induced acute interstitial nephritis and drug-induced glomerular diseases.

Antithyroid Arthritis Syndrome: A Case Report and Review of the Literature

We herein report the case of a 38-year-old Japanese woman with antithyroid arthritis syndrome who experienced severe migratory polyarthritis after the initiation of thiamazole therapy. The patient's symptoms promptly disappeared without any sequelae after the withdrawal of the drug. Antithyroid arthritis syndrome is poorly characterized, and the findings from our literature review indicate that this syndrome exhibits serological features that are distinct from those of antithyroid agent-induced vasculitis syndrome. The absence of autoantibodies, especially anti-neutrophil cytoplasmic antibodies, may help characterize and diagnose antithyroid arthritis syndrome. Furthermore, physicians' awareness of this syndrome is essential for its diagnosis in clinical practice.

Drug-induced glomerular disease: immune-mediated injury

Drug-induced autoimmune disease was initially described decades ago, with reports of vasculitis and a lupus-like syndrome in patients taking hydralazine, procainamide, and sulfadiazine. Over the years, multiple other agents have been linked to immune-mediated glomerular disease, often with associated autoantibody formation. Certain clinical and laboratory features may distinguish these entities from their idiopathic counterparts, and making this distinction is important in the diagnosis and management of these patients. Here, drug-induced, ANCA-associated vasculitis, drug-induced lupus, and drug-associated membranous nephropathy are reviewed.

Trojan horses: drug culprits associated with antineutrophil cytoplasmic autoantibody (ANCA) vasculitis

PURPOSE OF REVIEW

Antineutrophil cytoplasmic autoantibody (ANCA) vasculitis is a systemic autoimmune disease resulting in small-vessel inflammation caused by pathogenic autoantibodies directed against proteinase 3 or myeloperoxidase. Legal drug culprits have been implicated as causative agents in secondary forms of disease, and a recent burst of reports also implicate levamisole-adulterated cocaine as a culprit.

RECENT FINDINGS

Here, we briefly discuss all drug culprits associated with ANCA vasculitis and then focus on clinical, serologic, therapeutic and mechanistic aspects of four main drug culprits receiving attention of late, namely hydralazine, minocycline, propylthiouracil (PTU) and levamisole-adulterated cocaine.

SUMMARY

Hydralazine, minocycline, propylthiouracil and levamisole-adulterated cocaine use should be closely considered in any patient where ANCA vasculitis is entertained given the wide use of these drugs in the community. Furthermore, medical practitioners should test urine for the presence of cocaine in any patient with presumed ANCA vasculitis, and if positive, then urine should also be tested for levamisole. Clinical features can be severe requiring not only drug cessation and supportive care, but also immunosuppression, plasma exchange in severe cases and dialysis as needed. Clinical trial investigators should strongly consider excluding patients with drug-induced forms of disease and mechanistic inroads are greatly needed in these secondary forms of disease to help elucidate the underlying cause and pathogenesis of ANCA vasculitis.