Perinuclear anti-neutrophil cytoplasmic antibodies (p-anca) in chronic ulcerative colitis: Experience in a Mexican institution

AIM： To assess the prevalence and clinical value of p-ANCA in a sample of Mexican ulcerative colitis （UC） patients. METHODS： In a prospective, IRB-approved protocol, p-ANCA was determined in 80 patients with UC （mean age, 32 ± 12.9 years）. The severity and extension of disease were determined by clinical methods, searching a statistical association with p-ANCA status. RESULTS： p-ANCA were detected in 41 （51%） patients. Severity of disease was the only clinical variable statistically associated with their presence （P 〈 0.0001; OR = 9; CI 95% = 3.2-24.7）. CONCLUSION： The prevalence of p-ANCA was similar to that reported in other countries. Their presence was associated to UC severity, but offered no more information than the obtained by clinical methods.

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.

Update on Anti-Saccharomyces cerevisiae antibodies, anti-nuclear associated anti-neutrophil antibodies and antibodies to exocrine pancreas detected by indirect immunofluorescence as biomarkers in chronic inflammatory bowel diseases: Results of a multicent

AIM： Anti-Saccharomyces anti-nuclear associated cerevisiae antibodies （ASCA）, anti-neutrophil antibodies （NANA） and antibodies to exocrine pancreas （PAB）, are serological tools for discriminating Crohn＇s disease （CrD） and ulcerative colitis （UC）. Like CrD, coeliac disease （COD） is an inflammatory bowel disease （IBD） associated with （auto） antibodies. Performing a multicenter study we primarily aimed to determine the performance of ASCA, NANA and PAB tests for IBD diagnosis in children and adults, and secondarily to evaluate the prevalence of these markers in CoD. METHODS： Sera of 109 patients with CrD, 78 with UC, 45 with CoD and 50 healthy blood donors were retrospectively included. ASCA, NANA and PAB were detected by indirect immunofluorescence （IIF）. RESULTS： ASCA＋/NANA- profile displayed a positive predictive value of 94.2% for CrD. Detection of ASCA was correlated with a more severe clinical profile of CrD and treatment of the disease did not influence their serum levels. ASCA positivity was found in 37.9% of active CoD.PAB were found in 36.7% CrD and 13.3% CoD patients and were not correlated with clinical features of CrD, except with an early onset of the disease. Fifteen CrD patients were ASCA negative and PAB positive. CONCLUSION： ASCA and PAB detected by IIF are specific markers for CrD although their presence does not rule out a possible active CoD. The combination of ASCA, NANA and PAB tests improves the sensitivity of immunological markers for CrD. Repeating ASCA, NANA, and PAB testing during the course of CrD has no clinical value.

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.

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

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.

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.

Autoimmune liver disease-related autoantibodies in patients with biliary atresia

AIM To investigate the prevalence and clinical significance of autoimmune liver disease(ALD)-related autoantibodies in patients with biliary atresia(BA).METHODS Sera of 124 BA patients and 140 age-matched non-BA controls were assayed for detection of the following autoantibodies: ALD profile and specific anti-nuclear antibodies(ANAs), by line-blot assay; ANA and antineutrophil cytoplasmic antibody(ANCA), by indirect immunofluorescence assay; specific ANCAs and antiM2-3 E, by enzyme linked immunosorbent assay. Associations of these autoantibodies with the clinical features of BA(i.e., cytomegalovirus infection, degree of liver fibrosis, and short-term prognosis of Kasai procedure) were evaluated by Spearman's correlation coefficient.RESULTS The overall positive rate of serum autoantibodies in preoperative BA patients was 56.5%. ALD profile assay showed that the positive reaction to primary biliary cholangitis-related autoantibodies in BA patients was higher than that to autoimmune hepatitis-related autoantibodies. Among these autoantibodies, anti-BPO was detected more frequently in the BA patients than in the controls(14.8% vs 2.2%, P < 0.05). Accordingly, 32(25.8%) of the 124 BA patients also showed a high positive reaction for anti-M2-3 E. By comparison, the controls had a remarkably lower frequency of anti-M2-3 E(P < 0.05), with 6/92(8.6%) of patients with other liver diseases and 2/48(4.2%) of healthy controls. The prevalence of ANA in BA patients was 11.3%, which was higher than that in disease controls(3.3%, P < 0.05), but the reactivity to specific ANAs was only 8.2%. The prevalence of ANCAs(ANCA or specific ANCAs) in BA patients was also remarkably higher than that in the healthy controls(37.9% vs 6.3%, P < 0.05), but showed no difference from that in patients with other cholestasis. ANCA positivity was closely associated with the occurrence of postoperative cholangitis(r = 0.61, P < 0.05), whereas none of the autoantibodies showed a correlation to cytomegalovirus infection or the stages of liver fibrosis.CONCLUSION High prevalence of autoantibodies in the BA developmental process strongly reveals the autoimmunemediated pathogenesis. Serological ANCA positivity may be a useful predictive biomarker of postoperative cholangitis.

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.

Significance of anti neutrophil cytoplasmic antibodies in patients with pauci immune crescentic glomerulonephritis

Objective To evaluate the significance of serum anti neutrophil cytoplasmic antibodies (ANCAs) and the effects of immune suppressive treatments on its activity in patients with pauci immune crescentic glomerulonephritis (PICGN) Methods Serum ANCAs and myeloperoxidase (MPO) ANCA were detected by indirect immunofluorescence and enzyme linked immuno^sorbent assay (ELISA) methods respectively, and the renal tissues infiltrating cells including CD4 +, CD8 +, CD68 + and PCNA + cells were determined by four layer peroxidase antiperoxidase (PAP) method The clinical manifestations, pathologic features and immune pathologic changes in patients with positive ANCAs were compared with that in patients with negative ANCAs The effects of immune suppressive therapy on clinic and pathologic changes as well as ANCAs activity were also investigated in ANCAs positive and ANCAs negative patients Results Both of clinic active manifestations such as the degree of hematuria, rapidly progressive renal failure and pathologic active features including segmental capillary necrosis and vasculitis were much common in patients with positive ANCAs as compared with that in patients with negative ANCAs The number of infiltrating cells in renal tissue, especially CD4 + cells, was markedly higher in ANCAs positive patients than that in ANCAs negative patients The effects of immune suppressive therapy were also much better in patients with positive ANCAs than that in patients with negative ANCAs Conclusion Serum ANCAs is not only a marker for diagnosis of systemic vasculitis, but also a sensitive predictor for evaluation of diseases' activity and treatment in patients with PICGN The good effect of immune suppressive treatments on patients with PICGN is partially associated with the degree of ANCAs activity

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.

Clinical Predictors of Outcome in Patients with Anti-neutrophil Cytoplasmic Autoantibody-related Renal Vasculitis： Experiences from a Single-center

Background： Primary anti-neutrophil cytoplasmic antibody-associated vasculitis （AAV） is a chronic autoimmune disease associated with multisystem dysfunction. Renal involvement is common and closely associated with outcome. The purpose of this study was to investigate the clinical determinants of mortality of patients with AAV-related renal injury in the first 2 years after diagnosis in a single West Chinese center. Methods： Demographic and laboratory parameters of 123 consecutive patients with AAV-related renal injury diagnosed in Renal Division and Institute ofNephrology, Sichuan Provincial People＇s Hospital between 2004 and 2012 were collected retrospectively. All patients were followed up for 2 years after diagnosis. Survivors were compared with nonsurvivors to identify the clinical baseline variables associated with mortality. Multivariate Cox regression model was used to determine the independent predictors of mortality. Results： Of the 123 patients, 46 （37.4%） died by the end of 2 years after diagnosis, with 41 （33.3%） patients dying within the first 12 months. In comparison with the survivors, Birmingham Vasculitis Activity Score （BVAS）, the incidence of pulmonary hemorrhage and digestive system （DS） involvement, serum creatinine, and erythrocyte sedimentation rate were significantly higher in nonsurvivors, whereas lymphocyte counts, hemoglobin, and complement 3 （C3） were significantly lower. Renal replacement therapy was more common in nonsurvivors. High BVAS （hazard ratio [HR] = 1.058, 95% confidence interval [CI]： 1.002-1. I17; P = 0.042）, pulmonary hemorrhage （MR = 1.970, 95% CI： 1.033-3.757; P = 0.04）, DS involvement （HR = 2.911,95% （7：1.212-6.911 ： P = 0.017）4 and serum creatinine 〉400 μmol/L （MR = 2.910, 95% CI： 1.271-6.664, P = 0.012） were independent predictors of death in patients with AAV-related renal injury. Conclusions： Patients with AAV-related renal injury have high early mortality. Those with high BVAS （particularly with pulmonary or DS involvement） and serious renal dysfunction should receive aggressive therapy and careful monitoring to reduce the occurrence of adverse events and improve prognosis.

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.

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.

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.

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.

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.