Diagnosis and classification of polyarteritis nodosa

[Hughes-Stovin syndrome: a life-threatening manifestation of Behçet's syndrome]

Hughes-Stovin syndrome (HSS) is a systemic inflammatory condition of unknown origin that is considered to be part of the Behçet's syndrome (BS) spectrum. Recurrent venous thrombosis and superficial thrombophlebitis in combination with bilateral pulmonary artery aneurysms (PAA) represent the hallmark of HSS. The diagnostic evaluation includes computed tomography pulmonary angiography to detect signs of pulmonary vasculitis. The management of HSS is based on the European Alliance of Associations for Rheumatology (EULAR) recommendations for BS and mainly comprises immunosuppressive therapy with glucocorticoids and cyclophosphamide. In addition to drug therapy, PAA should be evaluated for interventional treatment. Spontaneous PAA rupture due to fragile vessel architecture can occur even in cases of remission and/or PAA regression.

Mitochondrial extracellular vesicles, autoimmunity and myocarditis

For many decades viral infections have been suspected as 'triggers' of autoimmune disease, but mechanisms for how this could occur have been difficult to establish. Recent studies have shown that viral infections that are commonly associated with viral myocarditis and other autoimmune diseases such as coxsackievirus B3 (CVB3) and SARS-CoV-2 target mitochondria and are released from cells in mitochondrial vesicles that are able to activate the innate immune response. Studies have shown that Toll-like receptor (TLR)4 and the inflammasome pathway are activated by mitochondrial components. Autoreactivity against cardiac myosin and heart-specific immune responses that occur after infection with viruses where the heart is not the primary site of infection (e.g., CVB3, SARS-CoV-2) may occur because the heart has the highest density of mitochondria in the body. Evidence exists for autoantibodies against mitochondrial antigens in patients with myocarditis and dilated cardiomyopathy. Defects in tolerance mechanisms like autoimmune regulator gene (AIRE) may further increase the likelihood of autoreactivity against mitochondrial antigens leading to autoimmune disease. The focus of this review is to summarize current literature regarding the role of viral infection in the production of extracellular vesicles containing mitochondria and virus and the development of myocarditis.

Overview of Vasculitides in Adults

Vasculitis is characterized by the inflammation of blood vessels. Vasculitides refers to the different forms of vasculitis, often classified according to the size of the blood vessel that is involved. Vasculitis may occur as a primary process or secondary to many systemic diseases. This topic provides an overview of the clinical features, diagnosis, and classification of the different forms of vasculitides.

Re-emphasising the importance of catheter-based angiography to differentiate polyarteritis nodosa from cutaneous arteritis: Two case reports

Polyarteritis nodosa (PAN) is a systemic necrotising vasculitis with a poor prognosis, characterised by inflammation and necrosis of medium-sized arteries. PAN patients can present with a wide range of systemic manifestations, whereas cutaneous arteritis (CA) is a restricted manifestation to skin of the disease with a more favourable prognosis. Thus, differentiation between PAN and CA is crucial. Here, we present two cases that were initially diagnosed as CA due to the limited presence of systemic symptoms, but were finally diagnosed as PAN through catheter-based angiography. Although contrast-enhanced computed tomography and computed tomographic angiography are increasingly used to diagnose PAN, neither case had any abnormal findings on these examinations. Our cases therefore underscore that catheter-based angiography is critical for differentiation between PAN and CA, even in cases with limited systemic symptoms.

Polyarteritis nodosa in a patient with chronic hepatitis B following COVID-19 vaccination: a case report

Different types of vasculitis have been reported after various vaccine administrations. Recently, the coronavirus disease 2019 (COVID-19) vaccine was one of the most common vaccine-induced vasculitis. Herein, we describe a 56-year-old male patient with chronic hepatitis B who presented with abdominal pain for 2 days, which was associated with vomiting and bloody diarrhea. He had a history of petechial rash for 25 days, multiple joint pain and lower limb weakness after the second dose of the COVID-19 vaccine. A skin biopsy showed medium-sized vessel vasculitis. Polyarteritis nodosa (PAN) was diagnosed depending on the American College of Rheumatology criteria. He was treated with steroids, plasmapheresis and antiviral medication with a good prognosis. In patients with a past medical history of chronic hepatitis B, the covid vaccine may be associated with an increased risk of developing a PAN, so clinicians should suspect the occurrence of this disease after COVID-19 vaccination.

Exploring Cardiovascular Manifestations in Vasculitides: An In-Depth Review

Systemic vasculitides encompass a cluster of autoimmune diseases that affect blood vessels, and are characterized by immune-mediated injury to either small- or large-sized blood vessels. Individuals afflicted with systemic vasculitides experience notable morbidity and mortality attributable to cardiovascular manifestations. Noteworthy among these are ischemic heart disease, venous thromboembolism, aortic involvement, valvular irregularities, myocarditis, and pericarditis. This narrative review investigated and evaluated the prevalent cardiovascular disturbances commonly associated with different types of vasculitides. This review also discusses the mechanisms that underlie these manifestations. It also provides a thorough explanation of the many diagnostic techniques essential for detecting the disease at its occult stage. It is essential for healthcare professionals to have knowledge of the cardiovascular complications caused by vasculitides, as this enables them to promptly recognize these symptoms and employ suitable diagnostic techniques early on. By doing so, timely detection can be ensured, which will subsequently aid in initiating appropriate treatment strategies that are vital for decreasing morbidity and mortality in patients with systemic vasculitides.

Intraperitoneal hemorrhage secondary to ruptured omental artery aneurysm associated with polyarteritis nodosa: a case report

BACKGROUND

Polyarteritis nodsa (PAN) is a rare disease characterized by acute focal inflammatory damage to small and medium arteries. PAN complicated by ruptured aneurysm is an infrequent presentation with the most affected arteries being the renal and mesenteric arteries.

CASE PRESENTATION

A 76-year-old female presented with a low-grade fever, generalized body aches, and abdominal pain. Investigation revealed intraperitoneal bleeding secondary to a ruptured and actively bleeding right omental artery aneurysm. Clinical manifestation, angiography and histology were consistent with PAN. Laparotomy was performed for stabilization and resection of the bleeding aneurysm followed by post operative steroids and cyclophosphamide. Patient was discharged in a stable condition. We reviewed seven cases found in the literature of omental artery aneurysm and rupture. Four cases were proceeded with laparotomy and aneurysm resection while three cases were proceeded with a less invasive approach of arterial embolization.

CONCLUSIONS

Omental artery aneurysm is a rare occurrence with even fewer reported cases associated with PAN. Of the seven reported cases, all patients were treated with a surgical intervention. In addition, PAN patients should be treated post-operatively with a course of steroids and cyclophosphamide.

Eosinophilic granulomatosis with polyangiitis - Advances in pathogenesis, diagnosis, and treatment

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare disease characterized by eosinophil-rich granulomatous inflammation and necrotizing vasculitis, pre-dominantly affecting small-to-medium-sized vessels. It is categorized as a primary antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) but also shares features of hypereosinophilic syndrome (HES); therefore, both vessel inflammation and eosinophilic infiltration are suggested to cause organ damage. This dual nature of the disease causes variable clinical presentation. As a result, careful differentiation from mimicking conditions is needed, especially from HES, given the overlapping clinical, radiologic, and histologic features, and biomarker profile. EGPA also remains a diagnostic challenge, in part because of asthma, which may pre-dominate for years, and often requires chronic corticosteroids (CS), which can mask other disease features. The pathogenesis is still not fully understood, however, the interaction between eosinophils and lymphocytes B and T seems to play an important role. Furthermore, the role of ANCA is not clear, and only up to 40% of patients are ANCA-positive. Moreover, two ANCA-dependent clinically and genetically distinct subgroups have been identified. However, a gold standard test for establishing a diagnosis is not available. In practice, the disease is mainly diagnosed based on the clinical symptoms and results of non-invasive tests. The unmet needs include uniform diagnostic criteria and biomarkers to help distinguish EGPA from HESs. Despite its rarity, notable progress has been made in understanding the disease and in its management. A better understanding of the pathophysiology has provided new insights into the pathogenesis and therapeutic targets, which are reflected in novel biological agents. However, there remains an ongoing reliance on corticosteroid therapy. Therefore, there is a significant need for more effective and better-tolerated steroid-sparing treatment schemes.

Characteristics of ANCA-associated vasculitis with aneurysms: Case series and review of the literature

INTRODUCTION

ANCA-associated vasculitis (AAV) is an exceptional cause of small and large vascular aneurysms. Here, we present the phenotypic characteristics of patients with AAV associated with the presence of aneurysms.

METHODS

We conducted a retrospective multicenter study and a systematic review of the literature. Only AAV patients with positive ANCA results and > 1 aneurysm(s) were enrolled. Patients were recruited through a call of observations among the French Vasculitis Study Group (FVSG) and the French Internal Medicine Network. Patients with aneurysm rupture were compared to those without.

RESULTS

We enrolled 51 patients in the cohort, including 31 (67%) with granulomatosis with polyangiitis. The median Birmingham Vasculitis Activity Score was 18 [6-41]. A total of 92 aneurysms were noted, 74% of which involved medium-sized arteries, particularly the renal artery. During a follow-up of 24 [6-56] months, 22 (43%) patients experienced aneurysmal rupture, 91% of which involved medium-sized vessels. Patients with aneurysmal rupture showed significantly more pulmonary infiltrates and higher creatinine levels at baseline than patients without rupture. Initial treatments did not differ between the two groups. Ten (20%) patients died during the follow-up, including three from an aneurysmal rupture.

CONCLUSION

Aneurysms were more frequently observed in GPA patients and predominantly affected medium-sized vessels, especially the renal arteries. The risk of rupture was high and occurred in >40% of patients. Because of their increased mortality, further studies are required to better manage this subset of patients.

Leg muscle involvement in polyarteritis nodosa (limited form)-A rare case report

Polyarteritis nodosa is a necrotizing arteritis involving small and medium vessels. Polyarteritis nodosa can have variable presentations depending upon the organ involved. It can either present as a diffuse disease or a limited form confined to a particular organ. Isolated muscular involvement in this disease is rare, which may present as myalgia, nonspecific fever, weight loss or even as claudication. The imaging pattern on ultrasound and MRI can help diagnose this condition in the background of clinical history and muscle biopsy is confirmatory. We present a case of 15 years old boy who presented with fever, weight loss, myalgia in leg region. MRI and ultrasound examination showed perivascular inflammation in calf muscles with a characteristic "cotton wool" pattern of enhancement on contrast study.

Positron Emission Tomography Imaging in Vasculitis

Systemic vasculitides comprise a group of autoimmune diseases affecting blood vessels. [18F]-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) plays an important role in the diagnosis and therapeutic monitoring of vasculitides affecting large-sized and medium-sized vessels. FDG-PET/CT also provides complementary information to other vascular imaging tools. The resolution and sensitivity of newer generation scanners continues to increase, hereby improving the ability of FDG-PET/CT to accurately assess the full disease extent in patients with vasculitis. Novel tracers targeting specific immune cells will allow for more detailed detection of vascular infiltrates.

Identifying risk and prognostic factors in polyarteritis nodosa patients with digital gangrene

BACKGROUND

Many patients with polyarteritis nodosa (PAN) complicated by digital gangrene have poor outcomes and related research information is limited. Our aim is to identify the associated risk and prognostic factors in PAN patients with digital gangrene.

PATIENTS AND METHODS

We conducted a retrospective study of 148 PAN patients admitted to Peking Union Medical College Hospital from Octorber 2001 to December 2018. Forty-seven (31.8%) PAN patients had digital gangrene. The average age was 40.4 ± 17.9 years.

RESULTS

The presence of digital gangrene was correlated with current smoking (P = .008, odds ratio [OR] 2.99, 95% CI, 1.33-6.73), eosinophil elevation (P = .003, OR 4.21, 95% CI, 1.62-10.91) and elevated leukocytes (P = .001, OR 4.26, 95% CI, 1.86-9.78). Thirty-two (68.1%) gangrene patients received methylprednisolone pulse therapy and all of these patients were treated with cyclophosphamide. Nine patients suffered irreversible organ injury and 2 died. Survival analysis showed higher serum C-reactive protein (CRP) was associated with poor prognosis in patients with gangrene (log-rank P = 0.042 and generalized Wilcoxon P = .020).

CONCLUSIONS

PAN patients with current smoking and eosinophil elevation were more prone to digital gangrene and a high serum CRP level predicted poor outcomes. The CRP level should be efficiently controlled to ensure a good prognosis.

Polyarteritis Nodosa Following mRNA-1273 COVID-19 Vaccination: Case Study and Review of Immunological Mechanisms

Numerous post-vaccine complications have been reported secondary to the COVID-19 vaccine. Many of these complications are believed to be due to a hyperactive immune system. A 59-year-old woman developed diffuse abdominal pain two days after receiving the mRNA-1273 COVID-19 vaccine (Moderna). A computerized tomography (CT) angiogram of the abdomen and pelvis revealed the presence of numerous vascular irregularities in the celiac axis, bilateral renal arteries, and inferior mesenteric artery consistent with polyarteritis nodosa (PAN), a medium-vessel vasculitis. The patient was managed with intravenous methylprednisolone 500 mg daily for three days and was then placed on oral methotrexate (MTX) 12.5 mg daily for immunosuppressive maintenance treatment. Until now, a limited number of cases of polyarteritis nodosa secondary to the COVID-19 vaccine have been reported. Major mechanisms of post-vaccine autoimmunity are molecular mimicry and autoantibody production. Although rare adverse events from COVID-19 vaccination are possible, there remains an immense benefit to vaccination in preventing COVID-19-related morbidity and mortality.

[Vasculitis as a cause of stroke]

The review considers the clinical picture, key aspects of the diagnosis and treatment of vasculitis that are the causes of strokes (giant cell arteritis, polyarteritis nodosa, varicella zoster virus vasculopathy, cerebrovascular pathology caused by herpes simplex virus types 1 and 2, primary CNS angiitis, adenosine deaminase-2 deficiency).

Hepatic artery pseudoaneurysms and hepatic ischaemic injury: a rare complication of polyarteritis nodosa

A woman in her 70s presented with months of intermittent fevers, severe fatigue, headaches, abdominal pain and haematuria. She developed acute onset left-sided weakness and was found to have radiographic evidence of right frontal and left parietal intraparenchymal haemorrhages with subarachnoid haemorrhage. She also had markedly elevated liver transaminases with subsequent abdominal MRI that revealed hepatic artery pseudoaneurysms (HAP) requiring embolisation. The case required a multidisciplinary approach consisting of hepatology, interventional radiology and rheumatology. Ultimately, the aetiology was attributed to polyarteritis nodosa (PAN). Through this case report, we highlight HAP as an extremely rare complication of PAN. Although it is a challenging diagnosis to make, it has a favourable response to immunosuppression with high-dose corticosteroids.

The neutrophil: A key resourceful agent in immune‐mediated vasculitis

The term "vasculitis" refers to a group of rare immune-mediated diseases characterized by the dysregulated immune system attacking blood vessels located in any organ of the body, including the skin, lungs, and kidneys. Vasculitides are classified according to the size of the vessel that is affected. Although this observation is not specific to small-, medium-, or large-vessel vasculitides, patients show a high circulating neutrophil-to-lymphocyte ratio, suggesting the direct or indirect involvement of neutrophils in these diseases. As first responders to infection or inflammation, neutrophils release cytotoxic mediators, including reactive oxygen species, proteases, and neutrophil extracellular traps. If not controlled, this dangerous arsenal can injure the vascular system, which acts as the main transport route for neutrophils, thereby amplifying the initial inflammatory stimulus and the recruitment of immune cells. This review highlights the ability of neutrophils to "set the tone" for immune cells and other cells in the vessel wall. Considering both their long-established and newly described roles, we extend their functions far beyond their direct host-damaging potential. We also review the roles of neutrophils in various types of primary vasculitis, including immune complex vasculitis, anti-neutrophil cytoplasmic antibody-associated vasculitis, polyarteritis nodosa, Kawasaki disease, giant cell arteritis, Takayasu arteritis, and Behçet's disease.

Medium-vessel Vasculitis Presenting with Myalgia Following COVID-19 Moderna Vaccination

Coronavirus disease 2019 (COVID-19) vaccines have been delivered worldwide to prevent the spread of the disease, and almost all Japanese have received the mRNA vaccines "BNT162b2" (Pfizer-BioNTech) or "mRNA-1273" (Moderna). These vaccines have shown efficacy and safety with only minor adverse drug reactions. However, some patients develop severe adverse drug reactions, including autoimmune reactions. In addition, systemic vasculitis, mainly small-vessel vasculitis, following COVID-19 vaccination, has been reported. However, only a few investigators have reported medium-vessel vasculitis following vaccination. We herein report a case of medium-vessel vasculitis presenting with myalgia as the initial clinical manifestation following COVID-19 Moderna vaccination.

Environmental Triggers for Vasculitis

Systemic vasculitides are autoimmune diseases characterized by vascular inflammation. Most types of vasculitis are thought to result from antigen exposure in genetically susceptible individuals, suggesting a likely role for environmental triggers in these conditions. Seasonal and geographic variations in incidence provide insight into the potential role of environmental exposures in these diseases. Many data support infectious triggers in some vasculitides, whereas other studies have identified noninfectious triggers, such as airborne pollutants, silica, smoking, and heavy metals. We review the known and suspected environmental triggers in giant cell arteritis, Takayasu arteritis, polyarteritis nodosa, Kawasaki disease, and antineutrophil cytoplasmic antibody-associated vasculitis.

A comprehensive guide for managing the reproductive health of patients with vasculitis

Vasculitides and their therapies affect all areas of the reproductive life cycle. The ACR, EULAR and the Drugs and Lactation database offer guidance on the management of the reproductive health of patients with rheumatic diseases; however, these guidelines do not address patients with vasculitis specifically. This Review discusses the guidance from multiple expert panels and how these recommendations might apply to men and women with vasculitis, including the safety of contraception, use of assisted reproductive technology, preservation of fertility during cyclophosphamide therapy, disease management in pregnancy and the use of medications compatible with pregnancy and lactation. These discussions are augmented by the existing literature on vasculitis in pregnancy to enable physicians to provide comprehensive, precise and high quality care to patients with vasculitis. The contents of this Review, in conjunction with educational tools, serve to empower patients and physicians to participate in shared decision-making regarding pregnancy prevention, planning and management.

This Review discusses how best to manage the reproductive health of patients with vasculitis, including the safety of contraception, the use of assisted reproductive technology, preservation of fertility during therapy, disease management in pregnancy and the use of medications compatible with pregnancy and lactation.

Rheumatologists have the opportunity to initiate discussions with patients with vasculitis regarding family planning to make proactive decisions leading to improved pregnancy planning, management and outcomes.

Birth control options and infertility interventions for women with vasculitis depend on their risk of thrombosis, serological profile and comorbid conditions.

The majority of pregnancies in patients with vasculitis can be successful with the use of advanced family planning, medications compatible with pregnancy and lactation, and multidisciplinary collaboration among specialists.

Vasculitis exacerbations and pregnancy complications can present with similar and overlapping clinical manifestations.

Multiple expert panels provide guidelines and risk stratification regarding medication use in pregnancy and breastfeeding that can be applied to patients with vasculitis.

Differential Diagnosis of Multiple Systemic Aneurysms

Atherosclerosis and systemic hypertension are the most common pathogeneses of solitary acquired arterial aneurysms. The rare occurrence of multiple synchronous or metachronous arterial aneurysms requires considering alternative underlying causes. We present the unusual case of a male patient who sequentially developed multiple co-existing arterial aneurysms between the ages of 51 and 59. The sites of involvement included high-pressure systemic arteries and low-pressure pulmonary arteries. We discuss the broad differential diagnosis that includes heritable and non-inheritable etiologies. A keen clinical awareness of this broader array of arterial aneurysms is essential for accurate early diagnosis and proper management.

Imaging of intestinal vasculitis focusing on MR and CT enterography: a two-way street between radiologic findings and clinical data

Diagnosis of intestinal vasculitis is often challenging due to the non-specific clinical and imaging findings. Vasculitides with gastrointestinal (GI) manifestations are rare, but their diagnosis holds immense significance as late or missed recognition can result in high mortality rates. Given the resemblance of radiologic findings with some other entities, GI vasculitis is often overlooked on small bowel studies done using computed tomography/magnetic resonance enterography (CTE/MRE). Hereon, we reviewed radiologic findings of vasculitis with gastrointestinal involvement on CTE and MRE. The variety of findings on MRE/CTE depend upon the size of the involved vessels. Signs of intestinal ischemia, e.g., mural thickening, submucosal edema, mural hyperenhancement, and restricted diffusion on diffusion-weighted imaging, are common in intestinal vasculitis. Involvement of the abdominal aorta and the major visceral arteries is presented as concentric mural thickening, transmural calcification, luminal stenosis, occlusion, aneurysmal changes, and collateral vessels. Such findings can be observed particularly in large- and medium-vessel vasculitis. The presence of extra-intestinal findings, including within the liver, kidneys, or spleen in the form of focal areas of infarction or heterogeneous enhancement due to microvascular involvement, can be another radiologic clue in diagnosis of vasculitis. The link between the clinical/laboratory findings and MRE/CTE abnormalities needs to be corresponded when it comes to the diagnosis of intestinal vasculitis.

Mesenteric Artery Dissection and Wall-Thickening, Case Study and General Review

Mesenteric artery dissection (D) and wall-thickening (WT) are rare vasculopathies that can lead to serious complications. This is a single center analysis of all patients evaluated for mesenteric arterial (celiac, superior (SMA) and/or inferior mesenteric (IMA)) D and/or WT from January 1, 2000, to January 31, 2020 at our hospital. Among the 101 included patients, the average age was 55.6 ± 13.6 years, mostly affecting men (62%). There were 20 celiac artery D, 8 WT, 15 D with WT, 15 SMA D, 7 WT, 8 D with WT, one IMA D, two WT, and 25 with multiple arterial involvement. Primary etiologies included segmental arterial mediolysis (SAM) (n = 17), isolated D (n = 17), localized vasculitis of the gastrointestinal tract (LVGT) (n = 16), fibromuscular dysplasia (FMD) (n = 13), extension of thoracoabdominal aortic D (n = 12), and trauma (n = 12). Most (71%) patients presented with abdominal pain. Hypertension (55%), hyperlipidemia (33%) and tobacco use (31%) were prevalent. Management included conservative (22%), medical (47%), endovascular (19%), and/or open repair (12%) with high in-hospital survival (98%) and symptom relief (73%). Our paper complements the scarce literature addressing the diagnosis and management of rare mesenteric vasculopathies. Most patients improved with conservative management, reserving endovascular or surgical interventions for symptomatic patients with more complicated presentations.

Polyarteritis nodosa presenting with posterior reversible leukoencephalopathy syndrome

A man in his 20s presented following a generalised tonic–clonic seizure on a background of a recent diagnosis of hepatitis B (HBV). During admission, he was severely hypertensive and imaging findings confirmed a diagnosis of posterior reversible leukoencephalopathy syndrome (PRES). The patient subsequently developed multiorgan involvement with an axonal sensorimotor neuropathy, vascular cutaneous lesions and multiple bilateral renal and splenic infarcts. Based on the 2012 Revised International Chapel Hill Consensus Criteria, a diagnosis of polyarteritis nodosa (PAN) with secondary PRES was made. The patient was given intravenous methylprednisolone, followed by a prolonged course of oral prednisolone, and tenofovir antiviral therapy to target HBV seroconversion. He made a good neurological recovery with resolution of imaging changes. This case highlights the importance of a low threshold for systemic screening for young patients presenting with PRES secondary to uncontrolled hypertension and the importance of viral screening, particularly for HBV.

Unusual presentation of familial Mediterranean fever with co‐existing polyarteritis nodosa and acute post‐streptococcal glomerulonephritis

Acute post‐streptococcal glomerulonephritis (APSGN) and polyarteritis nodosa (PAN) may occur simultaneously after streptococcal infection in a child who is previously healthy but carries a Mediterranean fever (MEFV) mutation. The homozygous M694V mutation in the MEFV gene may cause an augmented response to the streptococcal infection that plays a role in the development of both clinical manifestations.

Polyarteritis Nodosa with Cytomegalovirus Enteritis and Jejunoileal Perforation: Report of a Case with a Literature Review

Polyarteritis nodosa (PAN) is a rare systemic necrotizing vasculitis affecting small- to medium-sized arteries. The most common gastrointestinal manifestation of PAN is postprandial abdominal pain from mesenteric arteritis causing bowel ischemia. When transmural ischemia develops, there may be ischemic necrosis and perforation of the bowel wall, which are life-threatening. Severe, life-threatening gastrointestinal involvement is relatively rare in pediatric PAN and may require different management in adult patients. We report a pediatric PAN case in a patient who presented with acute abdominal pain and superimposed cytomegalovirus enteritis with jejunoileal perforation. The patient improved with emergency small intestinal resection followed by conventional immunosuppressive drugs of a corticosteroid and cyclophosphamide, and anti-viral drugs. Before increasing the immunosuppressive drug dosage, initial screening of infectious cytomegalovirus and comprehensive evaluation for surgical conditions are essential in pediatric PAN with severe gastrointestinal involvement. Early aggressive treatment for acute abdomen is useful in reducing morbidity and mortality in pediatric PAN.

Angiographic characteristics of vasculopathy in patients with idiopathic inflammatory myopathies and systemic sclerosis

To describe the peripheral angiographic features of vasculopathy in idiopathic inflammatory myopathies (IIM) and systemic sclerosis (SSc) in comparison to polyarteritis nodosa (PAN). Angiograms of 47 extremities (24 upper and 23 lower) of 11 patients with IIM (n = 5) and SSc (n = 6), and 12 patients with PAN who presented with critical limb ischemia were retrospectively analyzed with regards to the presence of stenosis, occlusion, aneurysms and delayed distal flow, and degree of neovascularization. Diffuse narrowing was more frequent (66.1 vs. 38.0%, p = 0.001), whereas multifocal stenosis (6.5% vs. 26.8%, p = 0.002), abrupt occlusion (11.3% vs. 29.6%, p = 0.010) and aneurysm formation (1.6% vs. 11.3%, p = 0.037) were less frequent in IIM/SSc than PAN. In distal arteries, tapered occlusion (95.5% vs. 76.0%, p = ns) and delayed flow (77.3% vs. 48.0%, p = 0.039) were more common in IIM/SSc than PAN. After 1 year, auto- or surgical amputation tended to be more frequent in IIM/SSc than PAN (36.4% vs. 16.7%, p = ns). In conclusion, diffuse narrowing, tapered occlusion and delayed distal flow on conventional angiograms tend to be more frequent in IIM/SSc than PAN. Further studies are needed to verify these findings in a larger prospective cohort.

Myocardial Infarction in a 7-Year-Old Girl with Polyarteritis Nodosa

Polyarteritis nodosa (PAN) is a rare systemic vasculitis that affects small to medium-sized arteries. It could affect any organ including the heart. However coronary artery involvements are very rare. We describe a young girl who presented following a histopathological diagnosis of PAN with acute chest pain, high serum troponin, and progressive ischemic changes in the electrocardiogram (ECG). Induction of remission of her disease was done with six-moths Cyclophosphamide infusions and pulse corticosteroids. In addition to anticoagulation and dual antithrombotic therapy, the disease remission was maintained with mycophenolate mofetil which helps in the recovery of coronary disease. Our case illustrates the serious cardiac involvement of PAN in a child that responded to intensive management.

Regulatory T Cells in Autoimmune Vasculitis

Blood vessels are indispensable for host survival and are protected from inappropriate inflammation by immune privilege. This protection is lost in patients with autoimmune vasculitides, a heterogeneous group of diseases causing damage to arteries, arterioles, and capillaries. Vasculitis leads to vascular wall destruction and/or luminal occlusion, resulting in hemorrhage and tissue ischemia. Failure in the quantity and quality of immunosuppressive regulatory T cells (Treg) has been implicated in the breakdown of the vascular immune privilege. Emerging data suggest that Treg deficiencies are disease-specific, affecting distinct pathways in distinct vasculitides. Mechanistic studies have identified faulty CD8+ Tregs in Giant Cell Arteritis (GCA), a vasculitis of the aorta and the large aortic branch vessels. Specifically, aberrant signaling through the NOTCH4 receptor expressed on CD8+ Treg cells leads to rerouting of intracellular vesicle trafficking and failure in the release of immunosuppressive exosomes, ultimately boosting inflammatory attack to medium and large arteries. In Kawasaki’s disease, a medium vessel vasculitis targeting the coronary arteries, aberrant expression of miR-155 and dysregulated STAT5 signaling have been implicated in undermining CD4+ Treg function. Explorations of mechanisms leading to insufficient immunosuppression and uncontrolled vascular inflammation hold the promise to discover novel therapeutic interventions that could potentially restore the immune privilege of blood vessels and pave the way for urgently needed innovations in vasculitis management.

A Rare Presentation of Polyarteritis Nodosa

Polyarteritis nodosa (PAN) is a rare form of necrotizing medium-vessel vasculitis. PAN has the potential for widespread organ involvement, but the skin, renal, neurologic, and musculoskeletal systems are most commonly involved. A definitive diagnosis can be made with a biopsy of an easily accessible organ such as the skin or an involved nerve or muscle. We present a case of a 66-year-old female with no significant past medical history who presented with chest and epigastric pain. She was subsequently found to have computed tomography angiography (CTA) findings consistent with PAN, including areas of arterial narrowing alternating with areas of aneurysmal dilation confined to the mesenteric arteries. A biopsy of the involved arteries was deemed unsafe and ultimately not performed. Her lab findings were remarkable for elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and unremarkable for a broad infectious disease workup. Suspicion of PAN was further strengthened by a positive response to, and eventual full recovery on, high-dose steroids alone.

Difficulties in Differentiating Hypertensive Disorders of Pregnancy With Polyarteritis Nodosa

Polyarteritis nodosa (PAN) is characterized by medium- or small-sized artery vasculitis with vessel wall inflammation and necrosis of muscular arteries, commonly presenting with fatigue, fever, weight loss, and joint pain. PAN in pregnancy is rare and is associated with worsening of vasculitis after delivery, resulting in myocardial infarction and heart failure which frequently lead to maternal death. We report a case of hypertensive disorders of pregnancy (HDP), which is difficult to differentiate from PAN. A 27-year-old multigravida was diagnosed with PAN 4 years prior after experiencing fever and lower extremity skin rash. During her PAN remission, she conceived her second pregnancy and opted to discontinue PAN medication and declined antihypertensive medications. At 22 weeks of gestation, her blood pressure was elevated to 200/100 mm Hg without proteinuria, for which she was admitted to our hospital. She was diagnosed with HDP-chronic hypertension without PAN recurrence due to the absence of PAN-specific skin or joint symptoms according to the PAN diagnostic criteria. Antihypertensive medication was administered. At 30 weeks of gestation, her blood pressure was poorly controlled and she developed proteinuria, which led to a diagnosis of superimposed preeclampsia that necessitated emergency cesarean section delivery. After delivery, her blood pressure was immediately controlled using antihypertensive medication. Our case report highlights the importance of carefully managing HPD as a serious complication of PAN.

Remission of Angiographically Confirmed Minocycline-induced Renal Polyarteritis Nodosa: A Case Report and Literature Review

A 23-year-old man presented with severe hypertension. Based on his history of minocycline treatment for over three years and clinical symptoms, such as myalgias and renovascular hypertension with multiple intrarenal aneurysms, he was diagnosed with minocycline-induced renal polyarteritis nodosa (PAN). After minocycline treatment cessation and management of the hypertension, his blood pressure, renin-aldosterone levels, and urinary protein levels gradually improved. Seven and a half years later, repeated angiography found that the aneurysms had resolved. This is the first report in English describing a case of minocycline-induced renal PAN that was reversed functionally and morphologically without steroids or immunosuppressive drugs.

Pancreaticoduodenal artery aneurysm associated with polyarteritis nodosa presenting as massive upper gastrointestinal bleeding

The pancreaticoduodenal arteries are rare sites for true aneurysm formation, but these may develop in association with occlusion of the coeliac circulation, degenerative conditions or inflammatory vascular disorders. These have a high risk of rupture regardless of size or other factors. One identified cause is polyarteritis nodosa (PAN), which is an autoimmune necrotising vascular condition that affects small-sized and medium-sized arteries. We report a case of a 40-year-old man with massive gastrointestinal tract bleeding from a ruptured pancreaticoduodenal artery aneurysm secondary to PAN. This was managed with emergent open aneurysm ligation followed by high-dose corticosteroids and cyclophosphamide pulse therapy. Only three other cases of PAN-associated pancreaticoduodenal artery aneurysms have been reported in the literature.

Hypertrophic pachymeningitis in polyarteritis nodosa: a case-based review

Hypertrophic pachymeningitis (HP) is a rare neurological disorder with focal or diffuse thickening of the dura mater, which usually causes headache, cranial neuropathies, seizures, and motor or sensory impairments. The development of HP is attributed to an immune-mediated mechanism, and some autoimmune diseases have been implicated in the development of HP. Herein, we describe the case of a 73-year-old woman with persistent headache ascribable to HP, which developed approximately 3 years after a diagnosis of polyarteritis nodosa (PAN). She was treated with high-dose corticosteroid and cyclophosphamide that resulted in immediate disappearance of headache and improved radiological findings of thickened dura mater. In addition, she was subsequently administered methotrexate, ultimately resulting in maintenance of remission and regular reduction of prednisolone. In our review of published English articles, only two cases of HP in patients with PAN have been reported to date, suggesting that HP is a rare complication in PAN. However, it should be recognized that HP may develop as a neurological involvement related to PAN.

Acute Neurologic Manifestations of Systemic Immune-Mediated Diseases

Systemic autoimmune diseases can affect the peripheral and central nervous system. In this review, we outline the common inpatient consultations for patients with neurological symptoms from rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus, sarcoidosis, immunoglobulin G4-related disease, Behçet's disease, giant cell arteritis, granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis, polyarteritis nodosa, and ankylosing spondylitis. We discuss the symptoms, diagnostic strategies, and treatment options.

Therapeutic options for cutaneous polyarteritis nodosa: a systematic review

OBJECTIVE

Cutaneous polyarteritis nodosa (CPAN) is a necrotizing vasculitis of the middle-size vessels, confined to the skin. We conducted a systematic review in order to identify studies evaluating the different treatment modalities used in CPAN.

METHODS

This systematic review was conducted according to PRISMA guidelines, registered in PROSPERO: CRD42020222195. PubMed/Medline databases were searched from inception to December of 2020 using the terms: (Polyarteritis nodosa[Title/Abstract]) AND ((therapy[Title/Abstract]) OR (management[Title/Abstract]) OR (treatment[Title/Abstract]))' and 'Cutaneous arteritis [Title/Abstract]'. Articles evaluating pertaining to the management of CPAN in adults were eligible for inclusion.

RESULTS

A total of seven eligible case series with 325 unique patients were included. No study included a control population. In general, systemic corticosteroids were widely used as induction treatment. Immunosuppressive agents combined with corticosteroids were AZA, hydroxychloroquine, sulfasalazine, sulphapyridine, CYC, MTX, mycophenolate, tacrolimus, rituxima and thalidomide. Other agents utilized in the studies were dapsone, colchicine, non-steroid anti-inflammatory drugs, salicylates, warfarin and clopidogrel. In some studies, the presence of ulcerations was associated with an increased risk of relapse.

CONCLUSION

The evidence available regarding the management of patients with CPAN is limited at best. Further studies are needed in order to evaluate the effect of treatment on disease remission, relapses and mortality.

2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Polyarteritis Nodosa

OBJECTIVE

To provide evidence-based recommendations and expert guidance for the management of systemic polyarteritis nodosa (PAN).

METHODS

Twenty-one clinical questions regarding diagnostic testing, treatment, and management were developed in the population, intervention, comparator, and outcome (PICO) format for systemic, non-hepatitis B-related PAN. Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel.

RESULTS

We present 16 recommendations and 1 ungraded position statement for PAN. Most recommendations were graded as conditional due to the paucity of evidence. These recommendations support early treatment of severe PAN with cyclophosphamide and glucocorticoids, limiting toxicity through minimizing long-term exposure to both treatments, and the use of imaging and tissue biopsy for disease diagnosis. These recommendations endorse minimizing risk to the patient by using established therapy at disease onset and identify new areas where adjunctive therapy may be warranted.

CONCLUSION

These recommendations provide guidance regarding diagnostic strategies, use of pharmacologic agents, and imaging for patients with PAN.

2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Polyarteritis Nodosa

OBJECTIVE

To provide evidence-based recommendations and expert guidance for the management of systemic polyarteritis nodosa (PAN).

METHODS

Twenty-one clinical questions regarding diagnostic testing, treatment, and management were developed in the population, intervention, comparator, and outcome (PICO) format for systemic, non-hepatitis B-related PAN. Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel.

RESULTS

We present 16 recommendations and 1 ungraded position statement for PAN. Most recommendations were graded as conditional due to the paucity of evidence. These recommendations support early treatment of severe PAN with cyclophosphamide and glucocorticoids, limiting toxicity through minimizing long-term exposure to both treatments, and the use of imaging and tissue biopsy for disease diagnosis. These recommendations endorse minimizing risk to the patient by using established therapy at disease onset and identify new areas where adjunctive therapy may be warranted.

CONCLUSION

These recommendations provide guidance regarding diagnostic strategies, use of pharmacologic agents, and imaging for patients with PAN.

Localized Forms of Vasculitis

Purpose of Review

To provide an updated review on epidemiology, clinical manifestations, diagnostic assessment, treatment, and prognosis of localized vasculitis, following the 2012 Revised International Chapel Hill Consensus Conference Nomenclature on single-organ vasculitis.

Recent Findings

Localized, single-organ vasculitides encompass a group of rare conditions in which there is no evidence of concomitant systemic vasculitis. Most data on this topic derives from case reports and small case series. Although some aspects of these diseases, such as clinical manifestations and histologic findings, have already been extensively investigated, there is still a lack of robust data concerning the pathogenesis, epidemiology, and treatment.

Summary

Localized vasculitides may have a wide range of clinical features depending on the organ affected. The inflammatory process may have a multifocal/diffuse or unifocal distribution. Diagnosis is usually based on histopathology findings and exclusion of systemic vasculitis, which may frequently pose a challenge. Further research on treatment is warranted.

Systematic review of childhood-onset polyarteritis nodosa and DADA2

BACKGROUND

Diagnosis of childhood polyarteritis nodosa (PAN) has become challenging after the definition of deficiency of adenosine deaminase 2 (DADA2). We aimed to define the differential features of pediatric PAN and DADA2 patients in our center and in the literature.

METHODS

The charts of pediatric PAN and DADA2 patients followed at the Pediatric Rheumatology Unit of Hacettepe University between 2010-2020 were analyzed. A systematic literature review was conducted for articles regarding pediatric PAN or DADA2.

RESULTS

Thirty-four pediatric PAN and 18 pediatric DADA2 patients were included. The age at onset was younger, parental consanguinity, livedo reticularis, neurologic involvement (especially strokes), lymphopenia, and hypogammaglobulinemia were more frequent, while thrombocytosis and panniculitis were less frequent in DADA2 patients. The primary treatment was anti-tumor necrosis factor (anti-TNF) in DADA2. For induction treatment, all systemic PAN patients received corticosteroids, and cyclophosphamide (n=11) or mycophenolate mofetil (MMF) (n = 3). Cyclophosphamide was replaced with MMF in nine once remission was confirmed with PVAS. In the literature, 28 articles describing 613 pediatric PAN patients and 26 articles describing 207 pediatric DADA2 patients were identified. Neurologic, gastrointestinal, and cardiac involvements were more frequent in DADA2, while constitutional symptoms and testis involvement were more common in PAN.

CONCLUSION

In a child with PAN-like phenotype, DADA2 should be considered in the presence of young age at disease onset, parental consanguinity, strokes, lymphopenia, and lack of thrombocytosis during active disease. Anti-TNF treatment is indicated for vasculitic DADA2. Cyclophosphamide could be switched to MMF when remission is confirmed with PVAS in severe PAN.

Clinical presentations and long term prognosis of childhood onset polyarteritis nodosa in single centre of Korea

Childhood-onset polyarteritis nodosa (PAN) is a rare and systemic necrotising vasculitis in children affecting small- to medium-sized arteries. To date, there have been only a few reports because of its rarity. Thus, we aimed to investigate the clinical manifestations, laboratory findings, treatment, and long-term outcomes in patients with childhood-onset PAN and to evaluate the usefulness of the paediatric vasculitis activity score (PVAS). We retrospectively analysed the data of nine patients with childhood-onset PAN from March 2003 to February 2020. The median ages at symptom onset, diagnosis, and follow-up duration were 7.6 (3–17.5), 7.7 (3.5–17.6), and 7.0 (1.6–16.3) years, respectively. All patients had constitutional symptoms and skin manifestations, while five exhibited Raynaud’s phenomenon. Organ involvement was observed in one patient. The median PVAS at diagnosis was 7 (range: 2–32). Prednisolone was initially used for induction in all patients, and other drugs were added in cases refractory to prednisolone. All patients survived, but three patients with high PVAS at diagnosis experienced irreversible sequelae, including intracranial haemorrhage and digital amputation. In conclusion, early diagnosis and treatment may minimise sequelae in patients with childhood-onset PAN. This study suggests that high PVAS score at diagnosis may be associated with poor prognosis.

Immune Axonal Neuropathies Associated With Systemic Autoimmune Rheumatic Diseases

Immune axonal neuropathies are a particular group of immune-mediated neuropathies that occasionally accompany systemic autoimmune rheumatic diseases such as connective tissue dissorders and primary systemic vasculitides. Apart from vasculitis of vasa nervorum, various other mechanisms are involved in their pathogenesis, with possible therapeutic implications. Immune axonal neuropathies have highly heterogeneous clinical presentation and course, ranging from mild chronic distal sensorimotor polyneuropathy to severe subacute mononeuritis multiplex with rapid progression and constitutional symptoms such as fever, malaise, weight loss and night sweats, underpinning a vasculitic process. Sensory neuronopathy (ganglionopathy), small fiber neuropathy (sensory and/or autonomic), axonal variants of Guillain-Barré syndrome and cranial neuropathies have also been reported. In contrast to demyelinating neuropathies, immune axonal neuropathies show absent or reduced nerve amplitudes with normal latencies and conduction velocities on nerve conduction studies. Diagnosis and initiation of treatment are often delayed, leading to accumulating disability. Considering the lack of validated diagnostic criteria and evidence-based treatment protocols for immune axonal neuropathies, this review offers a comprehensive perspective on etiopathogenesis, clinical and paraclinical findings as well as therapy guidance for assisting the clinician in approaching these patients. High quality clinical research is required in order to provide indications and follow up rules for treatment in immune axonal neuropathies related to systemic autoimmune rheumatic diseases.

Systemic vasculitides and the role of multitechnique imaging in the diagnosis

Vasculitis, a systemic disease characterised by inflammation of the blood vessels, remains challenging to diagnose and manage. Vessel size has been the basis for classifying systemic vasculitides. Imaging plays a vital role in diagnosing this challenging disease. This review article aims (a) to summarise up-to-date literature in this field, as well as include classification updates and (b) to review available imaging techniques, recent advances, and emphasis on imaging findings to diagnose large vessel vasculitides.