Diagnosis Of Microscopic Polyangiitis Research Articles

Role of bronchoscopy for respiratory involvement in granulomatosis with polyangiitis and microscopic polyangiitis.

This study describes data from bronchoscopy performed at the diagnosis of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). We conducted a retrospective study between 2004 and 2019 in patients aged >18 years with a diagnosis of microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA) who underwent bronchoscopy at onset of the disease. We collected bronchoalveolar lavage (BAL) and histological findings obtained during bronchoscopy. 274 patients with AAV were identified. Among 92 bronchoscopies, 62 were performed at diagnosis, and 58 procedures were finally analysed. Cough was more frequent in patients with MPA than GPA (p=0.02). The presence of endobronchial lesions (24.1%) was found to be significantly associated with GPA (p<0.0001) and proteinase 3-ANCA (p=0.01). The most frequent endobronchial lesions were inflammation and hyperaemia of the bronchial mucosa (50%), followed by stenoses (28%), ulcerations (21%) and mass-like granulomatosis (7%). The diagnostic yield of bronchial biopsies was useful for visible lesions (66.6% versus 0%; p=0.006). On BAL, diffuse alveolar haemorrhage (DAH) was detected in 31 (53.4%) patients and was more frequent in MPA patients (70.4% versus 38.7%; p=0.016). In 16.1% of DAH cases, BAL confirmed the diagnosis despite the absence of clinical or biological arguments. The incidence of microbial infections on BAL (38%) was similar between MPA and GPA (p=0.54). Bronchoscopy is an informative procedure at the onset of AAV disease in patients with respiratory manifestations. Endobronchial lesions are more frequently found in GPA and should be biopsied. BAL can be used to confirm DAH or diagnose superadded infection.

Pulmonary involvement in antineutrophil cytoplasmic antibody-associated vasculitides: A single center experience from Turkey.

Pulmonary involvement is an important cause of mortality and morbidity in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). In this study, we aimed to evaluate the type and frequency of pulmonary involvement and investigate the potential relationship between thorax computed tomography (CT) signs and other systemic clinical findings in AAV. A total of 63 patients over the age of 18 and diagnosed with AAV were included in this study. Thoracic CT imaging findings and clinical features of the patients at the time of diagnosis were retrospectively evaluated. The frequency and distribution of detected pathological findings on imaging according to disease types, in addition to the relationship of these findings with other systemic findings and disease severity, were analyzed. Of 63 patients, 50 (79.4%) had pulmonary symptoms at the time of presentation. Most frequently observed pulmonary finding of thorax CT was nodular opacity. Consolidation, cavitary nodules, bronchiectasis, emphysema and fibrotic sequelae change were more common in the patients with diagnosis of granulomatosis with polyangiitis. Honeycomb, atelectasis, interstitial pneumonia, pulmonary venous congestion and pleural effusion were more common in the patients with diagnosis of microscopic polyangiitis. Ground-glass appearance, central airway disease, peribronchovascular nodules, pericardial effusion and lymphatic adenomegaly (>10 mm) were more common in the patients with diagnosis of eosinophilic granulomatosis with polyangiitis. Interstitial lung disease, pulmonary hemorrhage and severe lung involvement were found significantly increased in patients with myeloperoxidase antibody (MPO)-ANCA positivity (P < 0.05). Lung involvement was detected in almost all of the patients with AAV. Both interstitial lung disease and severe lung involvement were more frequently found in patients with MPO-ANCA positivity compared to other patients. Pulmonary examination by an imaging technique in all patients with AAV may be useful to determine the vasculitis subtype and to determine the extent of the disease. Pulmonary involvement is quite common in AAV. Every patient with suspected AAV should be examined with imaging for lung involvement, even in the absence of respiratory symptoms. Severe pulmonary involvement is associated with the presence of severe disease and MPO-ANCA positivity.

69-Year-Old Man With Nasal Congestion and Pre-Syncope

69-Year-Old Man With Nasal Congestion and Pre-Syncope

Proteinuria Indicates Decreased Normal Glomeruli in ANCA-Associated Glomerulonephritis Independent of Systemic Disease Activity

Background: Renal involvement is a common and severe complication of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), potentially resulting in a pauci-immune necrotizing and crescentic ANCA glomerulonephritis (GN) with acute kidney injury (AKI), end-stage renal disease (ESRD) or death. There is recent evidence that the degree of proteinuria at diagnosis is associated with long-term renal outcome in ANCA GN. Therefore, we here aimed to systematically describe the association between proteinuria and clinicopathological characteristics in 53 renal biopsies with ANCA GN and corresponding urinary samples at admission. Methods: A total number of 53 urinary samples at admission and corresponding renal biopsies with confirmed renal involvement of AAV were retrospectively included from 2015 to 2021 in a single-center study. Results: Proteinuria correlated with myeloperoxidase (MPO) subtype, diagnosis of microscopic polyangiitis (MPA) and severe deterioration of kidney function. Proteinuria was most prominent in sclerotic class ANCA GN and ANCA renal risk score (ARRS) high risk attributed to nonselective proteinuria, including both glomerular and tubular proteinuria. Finally, there was no association between proteinuria and systemic disease activity, suggesting that proteinuria reflected specific renal involvement in AAV rather that systemic disease activity. Conclusions: In conclusion, proteinuria correlated with distinct clinicopathological characteristics in ANCA GN, mostly attributed to a reduced fraction of normal glomeruli. Furthermore, proteinuria in ANCA GN reflected specific renal involvement in AAV rather than systemic disease activity. Therefore, urinary findings could further improve our understanding of mechanisms promoting kidney injury and progression of ANCA GN.

Incidence of Tuberculosis in Systemic Necrotizing Vasculitides: A Population-Based Study From an Intermediate-Burden Country.

Objective: Tuberculosis (TB) has a significant impact on public health; however, its incidence in patients with systemic necrotizing vasculitides (SNV) remains unknown. Therefore, we evaluated the incidence of TB in patients with SNV using a nationwide claims database.Methods: The Health Insurance and Review Agency database was used to identify patients diagnosed with SNV between 2010 and 2018. The standardized incidence ratio (SIR) was calculated to compared the risk of TB between patients and the general population, based on the 2016 annual national TB report. The incidence of TB after SNV diagnosis was compared by estimating age- and sex- adjusted incidence rate ratio (IRR). A time-dependent Cox regression analysis was performed to estimate factors associated with TB.Results: Among the included 2,660 patients, 51 (1.9%) developed TB during the follow-up period. The risk of TB was significantly higher in patients with SNV [SIR 6.09, 95% confidence interval (CI) 4.53–8.00], both in men (SIR 5.95) and women (SIR 6.26), than in the general population; this increased risk was consistent in all disease subtypes, except eosinophilic granulomatosis with polyangiitis. Additionally, the incidence of TB was the highest in patients with SNV within the first 3 months after diagnosis (adjusted IRR: 8.90 compared to TB ≥ 12 months). In Cox regression analysis, the diagnosis of microscopic polyangiitis [hazard ratio (HR) 3.22, 95% CI 1.04–9.99], granulomatosis with polyangiitis (HR 4.63, 95% CI 1.53–14.02), and polyarteritis nodosa (HR 3.51, 95% CI 1.13–10.88) were independent factors associated with TB.Conclusion: Even when considering the high incidence of TB in the geographic region, the risk of TB increased in patients with SNV, with a difference based on disease subtypes. Moreover, taking into account of the high incidence of TB in SNV, vigilant monitoring for TB is required especially during the early disease period.

DIFFUSE ALVEOLAR HEMORRHAGE AS A CONSEQUENCE OF MICROSCOPIC POLYANGIITIS DUE TO COVID-19

SESSION TITLE: Fellows' COVID-19 SESSION TYPE: Fellow Case Reports PRESENTED ON: October 18-21, 2020 INTRODUCTION: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a small vessel vasculitis of which microscopic polyangiitis (MPA) is a subset. They are known to cause life threatening renal failure and/or pulmonary hemorrhage. Viruses are a known trigger of vasculitis, including MPA. (1) We present a case of MPA caused by COVID-19 presenting as diffuse alveolar hemorrhage (DAH) CASE PRESENTATION: 55 year old female with a past medical history of hemorrhagic stroke, hypertension & asthma who presented with respiratory distress & severe hypoxemia. At the time of intubation, a moderate amount of blood was suctioned from her endotracheal tube. She was profoundly hypoxemic & required 100% FiO2 and PEEP 18 cmH2O. A SARS CoV2 PCR test was positive. Other admission laboratory values were significant for a creatinine of 4.9 mg/dL (baseline: 0.8mg/dL), hemoglobin of 8 g/dL (baseline: 11.8g/dL), ferritin 569 ng/mL, D-dimer 3.18 ug/mL, CRP 62.8 mg/L, ESR 118 mm/hr. Chest X-ray showed dense bilateral airspace opacities. A CT scan showed extensive bilateral consolidations with air bronchograms that were not typical for a COVID-19 pneumonia (Image 1) except in the apices where these dense consolidations had a peripheral pattern. She was admitted to the medical ICU where she continued to have bleeding into her endotracheal tubing. Bronchoscopy showed blood in the airways diffusely with no focality to the bleeding. A bronchoalveolar lavage was performed of two separate lobes, and was notable for progressively bloody aliquots consistent with DAH. Because of concern for a pulmonary-renal syndrome, rheumatologic testing was performed. She was empirically treated with high dose intravenous steroids and plasmapheresis. Unfortunately, profound hypoxia persisted and family elected to withdraw life-sustaining therapies. Two days after her death, serologies revealed a mildly positive ANA and a strongly positive anti-MPO ANCA, suggesting the diagnosis of MPA. DISCUSSION: While the primary signs and symptoms of COVID-19 are fever, cough, and dyspnea, other reported manifesations include kawasaki-like disease in children (2) and cutaneous manifestations such as livedo reticularis (3). We believe that in our case the patient’s infection with COVID-19 & its subsequent increased inflammatory state led to her developing MPA vasculitis with subsequent pulmonary-renal syndrome complicated by diffuse alveolar hemorrhage, rapidly progressive renal failure and ultimately death. Her clinical and serologic picture were consistent with a diagnosis of microscopic polyangiitis. It is unclear whether our patient had a smoldering vasculitis that was triggered by the hyper-inflammatory nature of COVID-19 or whether this virus caused a vasculitis de novo. CONCLUSIONS: With vasculitis potentially being one of COVID-19's presenting symptoms, prompt diagnosis and intervention is essential in improving outcomes. Reference #1: Yates M, Watts R. ANCA-associated vasculitis. Clin Med (Lond). 2017;17(1):60-64. doi:10.7861/clinmedicine.17-1-60 Reference #2: Viner RM, Whittaker E. Kawasaki-like disease: emerging complication during the COVID-19 pandemic [published online ahead of print, 2020 May 13]. Lancet. 2020;10.1016/S0140-6736(20)31129-6. doi:10.1016/S0140-6736(20)31129-6 Reference #3: Sachdeva M, Gianotti R, Shah M, et al. Cutaneous manifestations of COVID-19: Report of three cases and a review of literature [published online ahead of print, 2020 Apr 29]. J Dermatol Sci. 2020;S0923-1811(20)30149-3. doi:10.1016/j.jdermsci.2020.04.011 DISCLOSURES: no disclosure on file for Christopher Damiano; No relevant relationships by Elie Fares, source=Web Response no disclosure on file for Catherine Kuntz; No relevant relationships by Kriti Pathak, source=Web Response

Microscopic polyangiitis secondary to Mycobacterium abscessus in a patient with bronchiectasis: a case report

BackgroundNon-Tuberculous Mycobacterial–pulmonary disease (NTM-PD) is increasing in incidence and prevalence. Mycobacterium abscessus (M.abscessus) is a rapid growing multi-resistant NTM associated with severe NTM-PD requiring prolonged antibiotic therapy. Complications of therapy are common but reports on direct complications of active NTM-PD are rare. Vasculitis has been described as a rare complication of NTM-PD, most often in individuals with inherited immune defects. This case is the first to describe an ANCA positive vasculitide (Microscopic Polyangiitis) secondary to M.abscessus pulmonary disease.Case presentationA 70 year old female with bronchiectasis underwent a clinical decline associated with the growth of M.abscessus and was diagnosed with NTM-PD. Before treatment could be initiated she developed small joint arthralgia and a glove and stocking axonal loss sensorimotor neuropathy. Positive Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (P-ANCA) and Myeloperoxidase-ANCA (MPO-ANCA) titres led to a diagnosis of microscopic polyangiitis. Further investigation revealed reduced interferon-gamma production but no other significant immune dysfunction.Dual treatment with immunosuppressive therapy (Corticosteroids/Cyclophosphamide) for vasculitis and antimicrobial therapy for M.abscessus NTM-PD was initiated. Clinical stability was difficult to achieve with reductions in immunosuppression triggering vasculitic flares. One flare led to retinal vein occlusion with impending visual loss requiring escalation in immunosuppression to Rituximab infusions. An increase in immunosuppression led to a deterioration in NTM-PD necessitating alterations to antibiotic regimes. Adverse effects including alopecia and Achilles tendonitis have further limited antibiotic choices resulting in a strategy of pulsed intra-venous therapy to stabilise NTM-PD.ConclusionsThis is the first reported case of an ANCA positive vasculitis secondary to M.abscessus pulmonary disease. This rare but important complication had a significant impact on the patient adding to the complexity of an already significant disease and treatment burden. The potential role of reduced interferon-gamma production in this case highlights the importance of investigating immune function in those with mycobacterial infection and the intricate relationship between mycobacterial infection and immune dysfunction. Immune dysfunction caused by genetic defects or immunosuppressive therapy is a known risk factor for NTM-PD. Balancing immunosuppressive therapy with prolonged antimicrobial treatment is challenging and likely to become more common as the number of individuals being treated with biologics and immunosuppressive agents increases.

Systemic vasculitis and the lung.

The purpose of this review is to provide a critical analysis of the recent literature on this topic, with particular focus on the most relevant studies published over the last year. Many studies are published every year on the diagnosis, pathogenesis and treatment of pulmonary involvement in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). The main subjects covered by this article are the pathogenesis, diagnosis and clinical aspects of lung involvement in ANCA-associated vasculitis and non-ANCA-associated vasculitis. Lung involvement is a common feature in systemic vasculitis. The lungs are one of the most frequently involved organs in systemic vasculitis. In order to provide an update on the recent advances in the pathogenesis, clinical features and novel treatments of lung involvement in systemic vasculitis, a systematic MedLine search has been performed.Most of the data analyzed have confirmed that lung involvement seems to develop more frequently in patients with myeloperoxidase-ANCA-positive AAV, mainly in those with a diagnosis of microscopic polyangiitis (MPA), compared with patients with proteinase 3 ANCA-positive AAV. Moreover, among non-ANCA-associated vasculitis lung involvement may represent a worrying complication of the disease, mainly when associated with vascular involvement.

We Present a Case of Cardiac and Ear Involvement as Atypical Manifestations of Microscopic Polyangiitis

A 43 year old Caucasian lady was admitted with palpitations and a non-productive cough. Two months before she had symptoms of left sided otalgia, otorrhoea and progressive hearing loss. This was treated with antibiotics with grommet inserts. Apart from sensorineural deafness, there was no other neurological abnormality. Cardiovascular and respiratory examination was unremarkable. Urine analysis showed + blood and ++ protein, with no casts. Blood tests showed a CRP of 254mg/L, white cell count of 14.6x10 9 /L, haemoglobin 99g/dl, creatinine 166µmol/L (eGFR 29mL/min) and troponin 538mmol/L, with subtle T wave flattening on ECG. An unclear picture led to a CT pulmonary angiogram, where incidental large bilateral renal haematomas were found, with no evidence of pulmonary emboli. Autoimmune tests showed ANCA positive with a raised MPO titre of 134U/ml. A renal angiogram showed renal artery aneurysms. A cardiac MRI showed features of myocarditis. A diagnosis of Microscopic Polyangiitis was made. She was treated with high dose steroids and oral cyclophosphamide with good resolution. In the absence of typical cardiovascular symptoms and normal ECG, cardiac MRI is a useful imaging technique to aid diagnosis. It is important to emphasise the need for classification of vasculitis for prognostic value and treatment duration.

Microscopic polyangiitis in a girl with severe anemia and no respiratory symptoms

ANCA-positive microscopic polyangiitis is a rare in children. We reported an 11-year-old girl without respiratory symptoms with sever anemia which shows signs of hemolytic anemia in test data. Chest X-ray and computed tomography scans suggested alveolar hemorrhage. The patent developed night hypoxia and moderate proteinuria. Serum MPO-antibody was highly positive and renal biopsy demonstrated segmental necrosis or crescent formation. A diagnosis of microscopic polyangiitis was made. She responded to pulsed methylprednisolon and pulsed Endoxan therapy. Microscopic polyangitiis should be considered early in the differential diagnosis of patients presenting with anemia of an unknown origin.

Acute vasculitis resulting in free flap failure: The importance of early recognition and options for management

Unusual or unexpected medical causes for free flap failure do occur but are uncommon. We present a rare case of a fibula free flap failure due to an acute vasculitis which was undiagnosed until after the flap had failed. In addition to two successful flap salvages and intravenous heparin, an epoprostenol infusion was commenced but a third salvage was not successful. The vasculitis resulted in marked blood vessel wall thickening, and cutaneous manifestations which presented as late signs. High peri-nuclear anti nuclear cytoplasmic antibody (pANCA) and myeloperoxidase (MOP) titres were subsequently found and histology from several blood vessels showed marked inflammation throughout the wall. A diagnosis of microscopic polyangiitis was made and high dose steroids were subsequently commenced. Interestingly, he had vasculitis several years previously treated with oral steroids but had been discharged from the rheumatology clinic. This rare case illustrates the potential hazards of free flap surgery in the vasculitides and discusses the warning signs and various management options to reduce the likelihood of flap failure in these patients.

Microscopic polyangiitis presenting with medullary infarct

Microscopic polyangiitis is a small vessel vasculitis which is rarely associated with ischemic stroke. Cerebrovascular disease has rarely been reported in connection with this disease. It may cause fatal hemorrhage, hemorrhagic conversion and multiple lacunar infarcts. We report here a 55-year-old woman with left medullary oblangata infarction without any symptoms of microscopic polyangiitis. During hospitalization, retinal ischemia, mononeuritis multiplex and pulmonary infiltration developed. Sural nerve biopsy was concomitant with small vessel vasculitis. Elevated CRP and sedimentation and positive P-ANCA led to confirmation of a diagnosis of microscopic polyangiitis. Our patient is a rare case of microscopic polyangiitis presenting with medullary infarction. Although the characteristics of this disease are well-known, the first symptom can be a medullary infarction, which has not been reported in literature before.

Identification of MPO-positive capillaries of the pleura by immunohistochemistry in MPO-ANCA associated vasculitis

We present a case of a middle-aged woman with myeloperoxidase anti-neutrophil cytoplasmic autoantibody (MPO-ANCA)-associated vasculitis that demonstrated immunohistochemically positive MPO capillaries of the pleura. The patient initially presented with proteinuria and microscopic hematuria at the age of 38. Acute progressive glomerulonephritis and pulmonary hemorrhage occurred 4 years later, and a high serum titer of MPO-ANCA was detected therefore a diagnosis of microscopic polyangiitis was made. Steroid-pulse therapy was performed and the pulmonary shadow improved, but the renal failure did not improve, thus, hemodialysis was initiated. Thereafter, an 18-year asymptomatic phase followed, but high serum levels of MPO-ANCA persisted during this period. Chronic pulmonary hemorrhage was discovered at the age of 60, and video-assisted thoracoscopic surgery was performed. Resected tissue revealed diffuse aloveolar hemorrhage accompanied by marked hemosiderin deposition, whereas MPO-immunopositive capillaries were identified only in the pleura. To our knowledge, this is the first report demonstrating MPO-positive capillaries in a disease other than glomerulonephritis. Judging from this unique case, MPO-positive endothelial cells may appear only during the hyperacute stage before hemorrhage, and may diminish thereafter, thus, may be associated with the trigger of microscopic polyangiitis.

Pulmonary consolidation with fever is not always pneumonia: A case of microscopic polyangiitis and review of the literature

Microscopic polyangiitis is a non-granulomatous, systematic and small-vessel vasculitis in which necrotizing glomerulonephritis is very common and pulmonary capillaritis often occurs. We report a patient with fever, fatigue and dry cough who initially had been diagnosed as having pneumonia. A thoracic CT was performed showing widespread multiple nodular lesions, some with a central air-bronchogram and thickened bronchovascular bundles and some connected to nodules. No cavitation or ground glass opacities were observed. Fibreoptic bronchoscopy was normal and the cultures from the BAL were negative. Additionally, during his stay in the hospital his hematocrit was gradually falling, while the erythrocyte sedimentation rate increased. Urinanalysis revealed proteinuria and active urinary sediment. p-ANCA was positive and renal biopsy revealed focal pauci-immune necrotic glomerulonephritis. Pulmonary–renal syndrome was suspected and renal biopsy was performed. The diagnosis of microscopic polyangiitis was established and the patient began treatment with pulse intravenous methylprednisolone and cyclophosphamide. After induction of remission, the patient received maintenance therapy. Finally, an extensive review of the literature on microscopic polyangiitis is presented.

Ocular Manifestations in Patients with Microscopic Polyangiitis

To describe ocular manifestations in patients with microscopic polyangiitis. Two patients with microscopic polyangiitis complained of ocular symptoms and underwent ophthalmologic examinations. An 83-year-old woman (Case 1) was diagnosed with microscopic polyangiitis, according to the general clinical findings and the presence of perinuclear pattern of antineutrophil cytoplasmic antibodies (P-ANCA). She had hypopyon iridocyclitis in the right eye and retinal cotton-wool spots in the left eye. The patient was treated with oral prednisolone and subconjunctival betamethasone. The hypopyon iridocyclitis and retinal cotton-wool spots responded. A 79-year-old man (Case 2) had bilateral scleritis. The diagnosis of microscopic polyangiitis was made based on general clinical findings and the presence of P-ANCA. Scleritis was reduced after corticosteroid treatment. Ophthalmologists should be aware that hypopyon iridocyclitis, cotton-wool spot, and scleritis could occur in patients with microscopic polyangiitis.

High proteinase 3-anti-neutrophil cytoplasmic antibody (ANCA) level measured by the capture enzyme-linked immunosorbent assay method is associated with decreased patient survival in ANCA-associated vasculitis with renal involvement.

Wegener granulomatosis (WG) and microscopic polyangiitis (MP), diseases associated with antineutrophil cytoplasmic antibodies (ANCA), had an extremely poor prognosis before the introduction of cyclophosphamide and corticosteroids for their treatment. However, there is still reduced patient survival, and some studies have documented severe side effects of the immunosuppressants used. This 10-yr follow-up study assessed 117 consecutive patients with WG or MP with biopsy-confirmed renal involvement. The cumulative relative patient survival was lower: 0.664 for women and 0.648 for men. The causes of death (n = 64) were in most cases registered as associated with the vasculitic disease. Analysis of possible predictive factors for patient survival by multiple Cox regression analysis revealed that a very high level of proteinase 3 (PR3)-ANCA measured by the capture ELISA method, a diagnosis of MP, and older age were factors predicting poorer patient survival. High levels of B-thrombocytes at time of diagnosis were associated with a better prognosis. For patients surviving the first year, remission-sustaining therapy with azathioprine for longer than 12 mo was associated with improved patient survival. Thirty-nine patients developed end-stage renal failure. Elevated serum creatinine at time of diagnosis and a very high level of PR3-ANCA by capture ELISA were factors predicting a higher risk for renal failure during follow-up. The epitope on PR3 assessed by capture ELISA needs to be further analyzed and explored: it seemed to implicate poorer patient and renal survival in WG or MP with renal involvement.

A Case of Microscopic Polyangiitis Presenting As Diffuse Alveolar Hemorrhage

A diffuse alveolar hemorrhage is a rare manifestation in microscopic polyangiitis. Recently we experienced a case of diffuse alveolar hemorrhage associated with microscopic polyangiitis, which was diagnosed with the typical clinical manifestations, ANCA and a renal biopsy. A 71 year old female was admitted complaining of coughing and dyspnea. A chest X-ray, HRCT and BAL revealed a diffuse alveolar hemorrhage. A diffuse alveolar hemorrhage was noted during a bronchoscopy. She also had proteinuria, microscopic hematuria and mild azotemia. The renal biopsy showed necrotic glomerulonephritis without immune complex deposits or granuloma. Under the diagnosis of microscopic polyangiitis, she was treated with steroid pulse therapy, and prednisolone with cyclophosphamide subsequently. She showed marked improvement in the clinical manifestations.