Myeloperoxidase-antineutrophil cytoplasmic antibody-associated vasculitis with headache and kidney involvement at presentation and with arthralgia at relapse:A case report

BACKGROUND Patients with proteinase 3-antineutrophil cytoplasmic antibody associated vasculitis(AAV)experience different manifestations at the initial onset and relapse.However,such cases of different initial and relapse manifestations have not been reported in myeloperoxidase(MPO)-AAV patients.CASE SUMMARY A 52-year-old woman was admitted to our hospital because of headache.Laboratory findings indicated nephrotic range proteinuria and microscopic hematuria,serum creatinine of 243μmol/L,anti-MPO antibody titer of>400 RU/mL,and positive perinuclearantineutrophil cytoplasmic antibody.Renal biopsy showed pauci-immune crescentic glomerulonephritis.The cerebrospinal fluid examination and brain magnetic resonance imaging did not show any abnormality.Therefore,MPO-AAV was diagnosed.Corticosteroids,plasmapheresis,and cyclophosphamide as induction therapy and mycophenolate mofetil(MMF)as maintenance therapy were administered.The patient’s headache disappeared;serum creatinine returned to normal;complete remission of microscopic hematuria and proteinuria was observed.Anti-MPO antibody titer reached normal limits after immunosuppressive treatment.Twenty-five months after stopping the immunosuppressive treatment,the patient relapsed with arthralgia,without neurological or renal involvement.The patient’s arthralgia improved after treatment with prednisone and MMF.CONCLUSION We have reported a rare case of MPO-AAV who initially presented with headache and kidney involvement.However,relapse presented with only arthralgia,which was completely different from the initial manifestations.This case suggests that AAV relapse should be highly suspected in MPO-AAV patients after remission,when clinical manifestations at relapse are different from those at onset.Prednisone and MMF may provide a good choice for refractory arthralgia during relapse in MPO-AAV patients.

Significance of antineutrophil cytoplasmic antibody in adult patients with Henoch-Schnlein purpura presenting mainly with gastrointestinal symptoms

AIM： To test the clinical significance of antineutrophil cytoplasmic antibody （ANCA） in evaluation of adult Henoch-Schonlein purpura （HSP） patients presenting mainly with abdominal symptoms. METHODS： Twenty-eight consecutive HSP patients who presented predominantly with abdominal symptoms were enrolled in this study. Control subjects included 27 ageand sex-matched patients with peptic ulcer disease, colon cancer, acute gastroenteritis, irritable bowel syndrome and colonic polyps. ANCA was measured by indirect immunofluorescence （IIF） in all patients, and follow-up ELISA was performed in patients with positive IIF tests. RESULTS： ANCA was detected in 9 HSP patients by IIF （2 were positive for c-ANCA and 7 were positive for p-ANCA）. No ANCA was found in the control group. The sensitivity and specificity of a positive ANCA test （either c- or p-ANCA） were 32.1% and 100% respectively. Only one out of the 9 patients with positive ANCA by IIF had positive ANCA by ELISA and the antigen was myeloperoxidase （MPO）. The patients positive for ANCA had higher HSP clinical scores, and were more likely to have renal function impairment. Patients with late purpura development were also associated with more severe clinical manifestations. CONCLUSION： A positive ANCA test is associated with more severe symptoms in HSP. After inflammatory bowel disease is excluded, a positive ANCA test provides a clue to the diagnosis of HSP presenting predominantly with abdominal symptoms.

A subset of ulcerative colitis with positive proteinase-3 antineutrophil cytoplasmic antibody

A small subset of patients with active ulcerative colitis is non-responsive to major known non-biological therapies. We reported 5 patients with positive serum proteinase-3 antineutrophil cytoplasmic antibody (PR3-ANCA) and tried to (1) identify the common clinical features of these patients; (2) investigate the efficacy of a novel therapy using a Chinese medicine compound; and (3) attract more gastroenterologists to be engaged in further study of this subset of patients. The common manifestations of disease in these 5 patients included recurrent bloody diarrhea and inflammatory lesions involving the entire colorectal mucosa. Initial treatment with intravenous methylprednisolone successfully induced remission. Four of these 5 patients were steroid-dependence, and immunosuppressants, such as azathioprine and cyclophosphamide, were in effective. In 3 patients, only the particular Chinese medicine compound could induce and maintain remission. One patient underwent colectomy. No vascular inflammatory lesions were found by histopathological examination. Although more cases are needed for confirmation, our study indicates thatulcerative colitis with positive PR3-ANCA may belong to a subtype of refractory ulcerative colitis. The particular Chinese medicine compound used in our study is by far the most effective in the management of these patients, with additional advantages of having no noticeable side-effects and less financial burden.

Systemic lupus erythematosus and antineutrophil cytoplasmic antibody-associated vasculitis overlap syndrome in a 77-year-old man: A case report

BACKGROUND Systemic lupus erythematosus(SLE)and antineutrophil cytoplasmic antibodyassociated vasculitis(AAV)are classically thought to cause renal impairment and small vessel vasculitis with different pathophysiologies.Their overlap constitutes a rare rheumatologic disease.To date,only dozens of such cases with biopsyproven glomerulonephritis have been reported worldwide typically in women of childbearing age.Here,we present a unique clinical case due to its rarity and individualized treatment of a Chinese man in his eighth decade of life.CASE SUMMARY A 77-year-old man was admitted to several hospitals for shortness of breath and received nonspecific treatments over the past 3 years.As his symptoms were not completely relieved,he visited our hospital for further treatment.Laboratory examinations revealed kidney dysfunction,severe anaemia,hypocomplementemia,glomerular proteinuria,and microscopic haematuria.Antinuclear antibodies,as well as anti-dsDNA antibodies,were positive.Computed tomography of the chest showed right pleural effusion.Renal biopsy was performed,and histology suggested crescentic glomerulonephritis,pauci-immune type.After treatment with plasmapheresis,glucocorticoid,and cyclophosphamide,the disease was in remission,and the patient remained in a stable condition for over 3 years post-hospital discharge.CONCLUSION Due to its complexity and rarity,SLE and AAV overlap syndrome is easily misdiagnosed.An accurate diagnosis and treatment at the earliest stage may significantly improve the condition and reduce irreversible organ injury.

Olfactory dysfunction in antineutrophil cytoplasmic antibodyassociated vasculitides: A review of the literature

Olfactory dysfunction(OD)has been described in patients with antineutrophil cytoplasmic antibody-associated vasculitides(AAV),but the underlying mechanisms are not completely understood.The causes of altered smell function can generally be divided into conductive,sensorineural or others.To date no specific treatment is available for AAV-related OD and the efficacy of currently available options has not been explored.The aim of this review is to provide an overview of the causes that may lead to OD in patients with AAV.Current available treatments for OD and possible options in patients with AAV presenting with smell impairment are also mentioned.

The role of mycophenolate in the treatment of antineutrophil cytoplasmic antibody-associated vasculitis

Mycophenolic acid, the active metabolite for mycophenolate mofetil and mycophenolic sodium, is a strong, noncompetitive, reversible inhibitor of inosine monophosphate dehydrogenase, the key enzyme in de novo synthesis of guanosine nucleotides leading to selective inhibition of lymphocyte proliferation. Mycophenolic acid has been evaluated as induction and remission maintenance agent in the treatment of antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Since the course of disease of AAV usually requires long term immunosuppression, mycophenolate has been explored as a less toxic agent compared to cyclophosphamide and azathioprine. Mycophenolate is a potent immunosuppressive agent in the therapy of AAV, non-inferior to other available drugs with comparable side effect profile. Therefore, it could be a valuable alternative in cases of toxicity with life threatening side effects or intolerance to cyclophosphamide or azathioprine, in cases with high cumulative dose of cyclophosphamide, but also in cases with insufficient response. Several studies have shown a higher relapse rate following discontinuation of mycophenolate or in mycophenolate treated subjects that raises concerns about its usefulness in the treatment of AAV. This review describes the efficacy of mycophenolate in AAV as remission induction agent, as remission maintenance agent, and as therapeutic option in relapsing AAV disease, the relapse rate following discontinuation of mycophenolate, and the adverse events related to mycophenolate treatment.

Antineutrophil cytoplasmic antibody associated vasculitides with renal involvement: Open challenges in the remission induction therapy

Renal involvement with rapidly progressive glomeru-lonephritis is a common manifestation of antineutrophil cytoplasmic antibody(ANCA) associated vasculitides, which is characterized by end-stage renal disease and high mortality rates in untreated and/or late referral patients. The long-term renal survival has improved dramatically since the addition of cyclophosphamide(CYC) and recently of rituximab(RTX) in association with corticosteroids in the remission induction thera-peutic regimens. However, renal prognosis remains unfavorable for many patients and the mortality rate is still significantly high. In this review, we analyze the open challenges to be addressed to optimize the induction remission therapy, principally in patients with advanced kidney failure. This concern the first-line therapy(CYC or RTX) based on different parameters(estimated glomerular filtration rate at baseline, new or relapsed disease, ANCA specificity, tissue injury, safety), the role of plasma exchange and the role of new therapies. Indeed, we discuss future perspectives in induction remission therapy by reporting recent advances in new targeted therapies with particular reference to avacopan, an orally administered selective C5a receptor inhibitor.

Dynamically changing antineutrophil cytoplasmic antibodies in granulomatosis with polyangiitis:A case report

BACKGROUND Granulomatosis with polyangiitis(GPA)is one of the most prevalent forms of the antineutrophil cytoplasmic antibody(ANCA)-associated vasculitis.GPA is characterized histologically by necrotizing granulomatous inflammation in addition to vasculitis.The diagnosis of GPA depends on clinical presentation,serological evidence of a positive ANCA,and/or histological evidence of necrotizing vasculitis or granulomatous destructive parenchymal inflammation.Cytoplasmic ANCA(c-ANCA)is positive in 65%-75% of GPA patients,accompanied by proteinase 3(PR3),the main target antigen of c-ANCA,another 5% of GPA patients had negative ANCA.CASE SUMMARY The patient,a 52-year-old male,presented with unexplained nasal congestion,tinnitus,and hearing loss.After a duration of 4 months experiencing these symptoms,the patient subsequently developed fever and headache.The imaging examination revealed the presence of bilateral auricular mastoiditis and partial paranasal sinusitis,and the ANCA results were negative.The anti-infective therapy proved to be ineffective,but the patient's symptoms and fever were quickly relieved after 1 wk of treatment with methylprednisolone 40 mg once a day.However,after continuous use of methylprednisolone tablets for 3 months,the patient experienced a recurrence of fever accompanied by right-sided migraine,positive c-ANCA and PR3,and increased total protein in cerebrospinal fluid.The and cyclophosphamide 0.8 g monthly,the patient experienced alleviation of fever and headache.Additionally,the ANCA levels became negative and there has been no recurrence.CONCLUSION For GPA patients with negative ANCA,there is a potential for early missed diagnosis.The integration of histopathological results and multidisciplinary communication plays a crucial role in facilitating ANCA-negative GPA.

Risk factors for renal outcomes in children with antineutrophil cytoplasmic antibody-associated vasculitis:a nationwide retrospective study in China

Background Pediatric antineutrophil cytoplasmic antibody-associated vasculitis(AAV)is a life-threatening systemic vasculitis featured by liability to renal involvement.However,there are few studies on the risk factors and predictive models for renal outcomes of AAV in children.Methods Data from 179 AAV children in multiple centers between January 2012 and March 2020 were collected retrospectively.The risk factors and predictive model of end-stage renal disease(ESRD)in AAV were explored.Results Renal involvement was the most typical manifestation(95.5%),and the crescent was the predominant pathological lesion(84.9%).The estimated glomerular filtration rate(eGFR)was evaluated in 114 patients,of whom 59.6%developed ESRD,and the median time to ESRD was 3.20 months.The eGFR[P=0.006,odds ratio(OR)=0.955,95%confidence interval(CI)=0.924–0.987]and the percentages of global glomerulosclerosis(pGGS;P=0.018,OR=1.060,95%CI=1.010–1.112)were independent risk factors for ESRD of renal biopsy.Based on the pGGS and eGFR at renal biopsy,we developed three risk grades of ESRD and one predictive model.The Kaplan‒Meier curve indicated that renal outcomes were significantly different in different risk grades(P<0.001).Compared with serum creatinine at baseline,the predictive model had higher accuracy(0.86 versus 0.58,P<0.001)and a lower coefficient of variation(0.07 versus 0.92)in external validation.Conclusions Renal involvement is the most common manifestation of pediatric AAV in China,of which more than half deteriorates into ESRD.The predictive model based on eGFR at renal biopsy and the pGGS may be stable and accurate in speculating the risk of ESRD in AAV children.

Animal models for anti-neutrophil cytoplasmic antibody-associated vasculitis:Are current models good enough?

Antineutrophil cytoplasmic autoantibody(ANCA)-associated vasculitis(AAV)is a rare and severe systemic autoimmune disease characterized by pauci-immune necrotizing inflammation of small blood vessels.AAV involves multiple organ systems throughout the body.Our knowledge of the pathogenesis of AAV has increased considerably in recent years,involving cellular,molecular and genetic factors.Because of the controlled environment with no other confounding factors,animal models are beneficial for studying the mechanistic details of disease development and for providing novel therapeutic targets with fewer toxic side effects.However,the complexity and heterogeneity of AAV make it very difficult to establish a single animal model that can fully represent the entire clinical spectrum found in patients.The aim of this review is to overview the current status of animal models for AAV,outline the pros and cons of methods,and propose potential directions for future research.

Antineutrophil cytoplasmic antibodies crescentic allograft glomerulonephritis after sofosbuvir therapy

Antineutrophil cytoplasmic antibodies(ANCA) are well known to be associated with several types of vasculitis, including pauci-immune crescentic glomerulonephritis, a form of rapid progressive glomerular nephritis(RPGN). ANCA vasculitis has also been reported after administration of propylthiouracil, hydralazine, cocaine(adulterated with levimasole), allopurinol, penicillamine and few other drugs. All previously reported cases of drug-associated ANCA glomerulonephritis were in native kidneys. Sofosbuvir is a new and effective drug for hepatitis C virus infection. Here, we report a case of ANCA vasculitis and RPGN following sofosbuvir administration in a kidney transplant recipient. It also represents the first case of drug-associated ANCA vasculitis in a transplanted kidney. Further drug monitoring is necessary to elucidate the degree of association and possible causal effect of sofosbuvir and perinuclear ANCA vasculitis.

Differentiation of Behcet's disease from inflammatory bowel diseases:Anti-saccharomyces cerevisiae antibody and anti-neutrophilic cytoplasmic antibody

The differential diagnosis of Behcet's disease(BD) from inflammatory bowel disease(IBD) is sometimes difficult and challenging.Hereby,we suggested the utility of anti-saccharomyces cerevisiae antibody(ASCA) and anti-neutrophilic cytoplasmic antibody(p-ANCA) in the differential diagnosis of BD from IBD.

rare type of pancreatitis as the first presentation ofanti-neutrophil cytoplasmic antibody-related vasculitis

A pancreatic tumor was suspected on the abdominal ultrasound of a 72-year-old man. Abdominal computed tomography showed pancreatic enlargement as well as a diffuse, poorly enhanced area in the pancreas; endoscopic ultrasound-guided fine needle aspiration biopsy and endoscopic retrograde cholangiopancreatography failed to provide a definitive diagnosis. Based on the trend of improvement of the pancreatic enlargement, the treatment plan involved follow-up examinations. Later, he was hospitalized with an alveolar hemorrhage and rapidly progressive glomerulonephritis; he tested positive for myeloperoxidase-anti-neutrophil cytoplasmic antibody(ANCA) and was diagnosed with ANCArelated vasculitis, specifically microscopic polyangiitis. It appears that factors such as thrombus formation caused by the vasculitis in the early stages of ANCArelated vasculitis cause abnormal distribution of the pancreatic blood flow, resulting in non-uniform pancreatitis. Pancreatic lesions in ANCA-related vasculitis are very rare. Only a few cases have been reported previously. Therefore, we report our case and a review of the literature.

Anti-Neutrophil Cytoplasmic Antibody Vasculitis in Pediatric Patients: Is the Incidence Rising?

Objectives: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is an autoimmune disease usually seen in middle-aged and older adults but which is rare in children and adolescents. We sought to determine if there has been a change in the incidence of this disorder. Methods: Single-center, retrospective review. Results: Over the last 2 years, we have encountered a striking increase in the frequency of this disease in pediatric patients. All eight patients seen during this period had renal involvement and 5 patients rapidly progressed to end stage kidney disease. The prognosis was worse in younger patients, those with microscopic polyangiitis, and those with chronic kidney damage in the diagnostic renal biopsy. Conclusions: We report these observations to highlight this change in the epidemiology of ANCA-associated vasculitis and to promote earlier recognition and treatment of this severe form of glomerulonephritis.

Mechanism of Anti-β-adrenoceptor Antibody Mediated Myocardial Damage in Dilated Cardiomyopathy

Antibodies against &-adrenoceptor can be detected in serum of patients with dilated cardiomyopathy (DCM), which have 5-agonist-like activity, and induce a positive chronotropic effect on cardiac myocytes by its persistence at full strength. Effects of the antibodies against Padrenoceptor from sera of patients with DCM on myocardial cytotoxicity and cytoplasmic free Ca2+-concentration (LCa2+ji) were observed in the cultured single layer SD rat ventricular cells by using the cytotoxicity assay and fluorescent Ca2+- indicat0r fura-2/AM. The positive sera of the anti-&adrenoceptor antibodies from patients with DCM markedly enhanced myocardial [Ca2+]i. Betaloc, a 5, -receptor blocker, might inhibit the increase of the antibody-mediated myocardial [Ca2+]i, and the sera from healthy donors had no effect on myocardial [Ca2+]i,. Our results suggest that the anti-β-adrenoceptor antibody might increase myocardial [Ca2+]i, and result in myocardial damage. The antibodies might activate receptor-gating Ca2+-channel, thereby causing myocardial [Ca2+]i, rise and calcium overload. Early use of betaloc is recommended in the treatment of dilated cardiomyopathy.

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 druginduced,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 druginduced 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 druginduced 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.

Propylthiouracil induced anti-neutrophil cytoplasmic antibody-associated vasculitis with bone marrow plasmacytosis and granulocytopenia

Antithyroid drugs are molecules known as thionamides that inhibit thyroid hormone synthesis by interfering with thyroid peroxidase mediated iodination of tyrosine residues in thyroglobulin. These extensively used drugs are associated with a variety of well-known side effects such as anti-neutrophil cytoplasmic antibody （ANCA）-positive vasculitis, granulocytopenia and aplastic anemia. Recently, an atypical hematological finding -- bone marrow plasmacytosis, related to the use of methimazole -- was reported twice in English literatures, but bone marrow plasmacytosis with the use of propylthiouracil （PTU） has hardly been reported so far. Herein we present a case of a patient with Graves＇ disease who was initially investigated for plasma cell dyscrasia but finally diagnosed as PTU-induced bone marrow plasmacytosis with granulocytopenia and ANCA-associated vasculitis.

Association between follistatin-related protein 1 and the functional status of patients with anti-neutrophil cytoplasmic antibody-associated vasculitis

Background:Follistatin-like 1(FSTL1)plays both pro-inflammatory and anti-inflammatory roles in the inflammatory processes.We investigated whether serum FSTL1 could predict the current anti-neutrophil cytoplasmic antibody-associated vasculitis(AAV)-specific indices.Methods:We randomly selected 74 patients with AAV from a prospective and observational cohort of Korean patients with AAV.Clinical and laboratory data and AAV-specific indices were recorded.FSTL1 concentration was determined using the stored sera.The lowest tertile of the short-form 36-item health survey(SF-36)was defined as the current low SF-36.The cutoffs of serum FSTL1 for the current low SF-36 physical component summary(PCS)and SF-36 mental component summary(MCS)were extrapolated by the receiver operator characteristic curve.Results:The median age was 62.5 years(55.4%were women).Serum FSTL1 was significantly correlated with SF-36 PCS(r=-0.374),SF-36 MCS(r=-0.377),and C-reactive protein(CRP)(r=0.307),but not with Birmingham vasculitis activity score(BVAS).In the multivariable linear regression analyses,BVAS,CRP,and serum FSTL1 were independently associated with the current SF-36 PCS(β=-0.255,β=-0.430,andβ=-0.266,respectively)and the current SF-36 MCS(β=-0.234,β=-0.229,andβ=-0.296,respectively).Patients with serum FSTL1≥779.8 pg/mL and those with serum FSTL1≥841.6 pg/mL exhibited a significantly higher risk of having the current low SF-36 PCS and SF-36 MCS than those without(relative risk 7.583 and 6.200,respectively).Conclusion:Serum FSTL1 could predict the current functional status in AAV patients.

Analysis of clinical features and prognosis of anti-glomerular basement membrane antibody positive patients with anti-neutrophil cytoplasmic antibodies

Objective To investigate the characteristics and outcome of glomerulonephritis in patients with both antineutrophil cytoplasmic antibody and anti-glomerular basement membrane antibody.Methods The sera of 23 antiGBM glomerulonephritis patients were collected and were tested for ANCA respectively.Characteristics and outcome of patients with coexisting anti-GBM antibody

Antineutrophil cytoplasmic antibodies-associated glomerulonephritis:From bench to bedside

Antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) is a group of autoimmune disorders that pre-dominantly affects small vessels. The onset of the disease is closely associated with ANCA. Renal involvement, also known as ANCA-associated glomerulonephritis (AGN), is one of the most common manifestations of AAV. In this mini-review, we described the clinical and pathological features of AGN. We then focused on recent studies on the mechanism of acute kidney lesions, including fibrinoid necrosis and crescent formation. Following the basic aspects of kidney injury in AGN, we demonstrated the clinical importance of kidney injury in determining the outcome of patients with AGN. The prognostic value of the 2010 Histopathological Classification of AGN and validating studies were summarized. Finally, treatment and novel therapeutic strategies were introduced addressing the importance of optimizing management of this patient population.