Pauci-immune Glomerulonephritis Research Articles

Antineutrophil cytoplasmic antibody-associated glomerulonephritis with immunoglobulin deposition.

Antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis is commonly classified as pauci-immune glomerulonephritis; however, some cases have granular immunoglobulin deposition along the glomerular capillary. The pathogenesis of immune deposits is poorly studied. Of 66 patients diagnosed with ANCA-associated glomerulonephritis on renal biopsy, cases with immunoglobulin deposition along the glomerular capillary were identified and their clinicopathological characteristics were analyzed. We also performed myeloperoxidase (MPO) and double immunofluorescence (IF) stainings to determine the presence of immune complex antigens. Granular IgG deposition, IgG plus IgM deposition, and IgM deposition were observed in 15 (22.1%), 8 (11.2%), and 17 (25.0%) cases, respectively. In cases with granular IgG deposition, MPO-IgG double IF staining revealed co-localization of MPO and IgG. In cases with granular IgM deposition, MPO-IgM double IF staining did not co-localize. By electron microscopy, subepithelial deposition as well as intramembranous, subendothelial, and mesangial deposition was detected in the patients with IgG deposition. In addition, renal survival curves were not significantly different between the immunoglobulin deposition and non-deposition groups. Granular IgG and/or IgM deposition was observed in 60.6% of patients with ANCA-associated glomerulonephritis. In cases with IgG deposition, electron-dense deposits (EDDs) were observed at various sites in the glomerulus, and MPO and IgG immunocomplex deposition was frequently observed along the glomerular capillary. With IgM deposition, EDDs were not obvious in the glomerular basement membrane, and MPO and IgM immunocomplex was not detected. These data suggest differential mechanism between IgG deposition and IgM deposition.

Pauci-immune crescentic glomerulonephritis associated with use of trimethoprim–sulfamethoxazole

Drug-induced pauci-immune crescentic glomerulonephritis has been described with several agents, including propylthiouracil, minocycline, D-penicillamine, and hydralazine. We present the case of a 60-year-old man who presented with rapidly progressive glomerulonephritis in the setting of recent use of trimethoprim-sulfamethoxazole complicated by the development of the Stevens-Johnson syndrome, and was found to have biopsy-proven pauci-immune crescentic glomerulonephritis and undetectable anti-neutrophilic cytoplasmic antibodies. We review the existing literature on the potential association between sulfonamides and hypersensitivity polyangiitis.

Epidemiology of Glomerular Disease in Southern Arizona: Review of 10-Year Renal Biopsy Data.

Glomerulonephritis stands third in terms of the etiologies for end-stage kidney disease in the USA. The aim of this study was to look at the patterns of biopsy-proven glomerulonephritis based on data from a single center.Kidney biopsy specimens of all patients above the age of 18 years, over a 10-year period, who had diagnosis of nondiabetic glomerular disease, were selected for the study.The most common histopathological diagnosis was focal and segmental glomerulosclerosis (FSGS) (22.25%, 158/710) followed by membranous nephropathy (20.28%, 144/710) and immunoglobulin (Ig)A nephropathy (19.71%, 140/710). There was male preponderance in all histological variants except IgA nephropathy, lupus nephritis, and pauci-immune glomerulonephritis. The race distribution was uneven, and all histological variants, except minimal change disease and lupus nephritis, were more commonly seen in whites. In a separate analysis of the histological pattern in Hispanics, lupus nephritis was the most common pathology (28.70%, 62/216) followed by FSGS (18.05%, 39/216). In American Indian population, the most common pathology was IgA nephropathy (33.33%, 8/24) followed by FSGS (16.67%, 4/24).This study highlights the histopathological patterns of glomerular disease in southern Arizona. The data suggest regional and ethnic variations in glomerular disease that may point towards genetic or environmental influence in the pathogenesis of glomerular diseases.

Systemic Lupus Erythematosus and Antineutrophil Cytoplasmic Antibody-Associated Vasculitis Overlap Syndrome in Patients With Biopsy-Proven Glomerulonephritis

The aim of the study was to report the clinical, biological, and pathological characteristics of patients with glomerulonephritis (GN) secondary to systemic lupus erythematosus (SLE)/antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) overlap syndrome.A nationwide survey was conducted to identify cases of SLE/AAV overlap syndrome. Data were collected from SLE and AAV French research groups. Inclusion criteria were diagnosis of both SLE and AAV according to international classification criteria and biopsy-proven GN between 1995 and 2014. Additional cases were identified through a systematic literature review. A cohort of consecutive biopsy-proven GN was used to study the prevalence of overlapping antibodies and/or overlap syndrome.The national survey identified 8 cases of SLE/AAV overlap syndrome. All patients were female; median age was 40 years. AAV occurred before SLE (n = 3), after (n = 3), or concomitantly (n = 2). Six patients had rapidly progressive GN and 3/8 had alveolar hemorrhage. All patients had antinuclear antibodies (ANA); 7/8 had p-ANCA antimyeloperoxidase (MPO) antibodies. Renal biopsies showed lupus nephritis (LN) or pauci-immune GN. Remission was obtained in 4/8 patients. A literature review identified 31 additional cases with a similarly severe presentation. In the GN cohort, ANCA positivity was found in 30% of LN, ANA positivity in 52% of pauci-immune GN, with no correlation with pathological findings. The estimated prevalence for SLE/AAV overlap syndrome was 2/101 (2%).In patients with GN, SLE/AAV overlap syndrome may occur but with a low prevalence. Most patients have an aggressive renal presentation, with usually both ANA and anti-MPO antibodies. Further studies are needed to assess shared pathogenesis and therapeutic options.

Treatment of Relapsing Pulmonary Hemorrhage in a Patient With ESRD Due to Pauci-Immune Glomerulonephritis (GN)

Treatment of Relapsing Pulmonary Hemorrhage in a Patient With ESRD Due to Pauci-Immune Glomerulonephritis (GN)

ATYPICAL PRESENTATION IN A CASE OF GRANULOMATOSIS WITH POLYANGIITIS

Granulomatosis with polyangiitis (GPA) is part of the anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitis, mostly being ANCA-c (anti proteinase 3) positive. Primarily it involves the upper respiratory tract and kidneys having an increased mortality in the absence of early diagnosis and correct treatment. The most common renal involvement is pauci-immune crescentic glomerulonephritis. We present the case of a patient with GPA with a particular onset of interstitial nephritis, possible by vasa recta vasculitis, in the absence of glomerulonephritis.

The predictive value of kidney biopsy in renal vasculitis: a multicenter cohort study

The histopathologic classification of antineutrophil cytoplasmic antibody-associated vasculitis has been demonstrated to have prognostic value in small cohorts of patients with pauci-immune extracapillary glomerulonephritis. We aimed to validate this histologic subgrouping system in a large cohort of patients with renal vasculitis from 3 Spanish centers. The additional value of several histologic parameters for predicting renal outcome was investigated. A total of 151 biopsies of patients with renal vasculitis were reviewed and classified as follows: 41% crescentic, 24% mixed, 21% focal, and 14% sclerotic. The cumulative proportions of renal survival at 5 years were 83.2%, 81.2%, 60.5%, and 50.7% for the focal, mixed, crescentic, and sclerotic categories, respectively (P < .05). In the crescentic category, patients with less than 75% of glomeruli showing crescents had better survival at 1 and 5 years compared with those having greater than or equal to 75% of crescents (77.9% and 70.6% versus 51.3% and 45.6%; P = .02). When adjusted by renal function and other histologic parameters, the percentage of extracapillary proliferation and glomerulosclerosis remained as significant predictors for renal survival (hazard ratio, 1.03; 95% confidence interval, 1.01-1.05; P = .001, and hazard ratio, 1.03; 95% confidence interval, 1.01-1.05; P = .002, respectively). In conclusion, patients with pauci-immune crescentic glomerulonephritis experienced different outcomes depending on the percentage of crescents observed, so that extensive extracapillary proliferation was associated with the poorest renal survival. These findings validate the prognostic utility of the histologic classification scheme in antineutrophil cytoplasmic antibody positive and negative patients and suggest a subdivision of crescentic category (<75% and ≥75% of crescents) based on the different survival rates observed among these subgroups.

Anti-CD20 therapy and pauci-immune crescentic glomerulonephritis.

Pauci-immune glomerulonephritis represents an important cause of crescentic glomerulonephritis, which may be renal-limited vasculitis or part of systemic vasculitis, i.e., microscopic polyangiitis, granulomatosis with polyangiitis (previously known as Wegner’s granulomatosis) and eosinophilic granulomatosis with polyangiitis (previously known as ChurgeStrauss Syndrome). While the presence of antineutrophil cytoplasmic antibody (ANCA) serves a diagnostic tool and leads to the term “ANCA-associated vasculitis,” these autoantibodies are also involved in the pathogenesis. Moreover, there are reports of a positive correlation between B cell activation status and disease activity and the central role of B cells is further supported by reports mentioning that the cyclophosphamide effect is mediated through the suppression of B-cell functions. Thus, suppression of antibody production by Bcell depleting agents to reduce ANCA levels becomes appealing. The murine-human chimeric anti-CD20 monoclonal antibody rituximab depletes B cells and suppresses the production of antibodies. Moreover, rituximab affects other B cell-mediated processes, including but not limited to antigen presentation, cytokine production, and B cell:T cell costimulation, and was associated with the expansion of

Pattern of biopsy-proven kidney disease in the elderly in a tertiary care hospital in India: a clinicopathological study.

An aging population is an important demographic issue in India. The knowledge base about kidney diseases among the elderly Indians is inadequate. We aim to delineate the clinical profile and spectrum of biopsy-proven kidney disease in elderly patients. Records of all elderly patients (≥60 years) who had undergone kidney biopsy in the nephrology department from January 2010 to December 2014 were reviewed. Their clinical details and laboratory investigations at the time of biopsy were noted. Details of kidney biopsy were recorded from their biopsy reports. In total, 1728 patients underwent kidney biopsy during this period and 124 were elderly (7.2%). Their mean age was 64.9 ± 4.9 years, and they were predominantly males (63.7%). Mean serum creatinine was 3.0 ± 2.8 mg/dl, proteinuria was 4.0 ± 2.7 g/day, and 39.5% had microscopic hematuria. The most common indications for biopsy were nephrotic syndrome (NS)--39.5% and acute kidney injury/rapidly progressive glomerulonephritis (AKI/RPGN)--24.2%. Another 8.1% patients had NS with AKI. MN (39.0%) was the chief cause of NS, and pauci-immune crescentic glomerulonephritis (GN) (28.2%) was the leading cause of AKI/RPGN. MN, pauci-immune crescentic GN and acute on chronic tubulointerstitial nephritis (A/CTIN) and acute tubular injury (ATI) were more common in the elderly, while MCD, FSGS, IgA nephropathy and lupus nephritis were more frequent in the younger patients. 68.5% of the elderly patients biopsied were diagnosed with a renal disease which was potentially amenable to specific treatment. The spectrum of biopsy-proven kidney disease in the elderly Indians seen in our tertiary care hospital varies from the younger population. Kidney biopsy provides useful information with therapeutic and prognostic implications in these patients. The percentage of elderly patients among the total biopsied population is low in India, and these patients present late with renal dysfunction. Prospective studies are needed to assess the outcome of the commonly seen kidney diseases in elderly patients.

PROBLEMS IN THE DIAGNOSIS AND TREATMENT OF ANCA-ASSOCIATED SYSTEMIC VASCULITIS: IN THE FOCUS OF ANCA-NEGATIVE PAUCI-IMMUNE GLOMERULONEPHRITIS

One of the most common causes of rapidly progressive glomerulonephritis (GN) is the so-called pauci-immune crescentic GN that is characterized by no luminescence in kidney tissue samples during immunofluorescence microscopy and by the hyperproduction of antineutrophil cytoplasmic antibodies (ANCA). At the same time, serum ANCAs are absent in a number of cases of pauci-immune GN. Based on their own experience, the authors present the clinical and morphological characteristics of patients with ANCA-negative pauci-immune GN and analyze the data available in the literature. Subjects and methods. This retrospective study included 8 patients with ANCA-negative pauci-immune GN, who were followed up at two Russian centers (the Center of Nephrology and the Center of Rheumatology) in 2011 to 2015. Results and discussion. According to our data, ANCAs are not detectable in 6% of the patients with ANCA-associated systemic vasculitis (SV) with renal involvement and/or pauci-immune GN. The mean age at onset of the disease in the ANCA-negative patients was 50±18 years (range 19 to 74 years); the male/female ratio was 1:1. Four (50%) cases were diagnosed with microscopic polyangiitis; 2 cases had granulomatosis with polyangiitis; isolated renal injury was present in other 2 patients. The Birmingham SV activity index averaged 19.6±7.9. Hematuria was observed in all cases and it was massive in 4. The mean daily urinary protein level was 3.4±2.7 g; three (38%) patients were observed to have nephrotic syndrome. The blood creatinine level averaged 704±405 μmol/l; GN was characterized by a rapidly progressive course in 6 (75%) patients; hemodialysis was needed in 5. A morphological study of the kidney determined crescents (in on an average of 52 glomeruli) in the majority of cases and glomerulosclerosis in one patient. All the patients were observed to have varying degrees of interstitial fibrosis. Three (38%) treated patients achieved remission. The mortality rates were 38%. Interestingly, the data from our group as well those obtained by the study of European cohorts were slightly different from those of the studies conducted in Asia, according to which a renal biopsy more frequently revealed glomerular crescents; the levels of protein in the urine were higher and renal survival was worse. Thus, serum ANCAs are absent in 3–39% of cases of pauci-immune crescentic GN, but the clinical and morphological picture corresponds to ANCA-associated SV. A kidney biopsy helps establish the correct diagnosis, timely use induction treatment, and improve prognosis.

Behçet's Disease and Anti-neutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis

Behçet's disease (BD) is a multisystem disorder of unknown etiology. Renal involvement in Behçet's disease is not frequent. Pauciimmune necrotizing and crescentic glomerulonephritis is associated with antineutrophil cytoplasmic antibodies (ANCA) which are believed to activate neutrophils and cause vasculitis, especially if there is a concurrent synergistic inflammatory process. In this case report, we describe a patient diagnosed with BD who also developed pauciimmune necrotizing and crescentic glomerulonephritis. We also compared this case with similar previous cases reported in the literature. The aim of this study is to add information regarding ANCA, pauciimmune glomerulonephritis and Behçet's disease.

Granulomatosis with Polyangiitis Presenting as Pauci-Immune Crescentic Glomerulonephritis in Pregnancy.

Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis rarely affects females of reproductive age. A 28-year-old African American woman presented at 8 weeks of gestation with intractable vomiting attributed to hyperemesis gravidarum. She was found to have acute kidney injury that was unresponsive to vigorous fluid resuscitation and urine sediment examination was suggestive of an underlying glomerulonephritis. Serum c-ANCA and PR3 were elevated and there was no peripheral eosinophilia. During her course she also developed one episode of small volume hemoptysis with right upper lobe infiltrates on CT Chest. There were no cutaneous manifestations of vasculitis or upper respiratory symptoms. Renal biopsy revealed a pauci-immune crescentic glomerulonephritis (PICGN). The diagnosis was consistent with granulomatosis with polyangiitis (GPA). Management initially comprised teratogen sparing agents; steroids, intravenous immunoglobulin; and plasma exchange. The response was suboptimal and she became dependent on daily renal replacement therapy. Ultimately the pregnancy was terminated allowing for traditional treatment approaches with dramatic effect. This is the first case of GPA presenting as PICGN in pregnancy and highlights the challenges of its management.

Clinical spectrum and outcomes of crescentic glomerulonephritis: A single center experience.

There is limited data on the etiology, clinical and histopathological spectrum and outcomes of crescentic glomerulonephritis (CrGN) in adult Indian population. This prospective study was done to evaluate the etiology, clinicohistological patterns and predictors of outcome of CrGN in South Indian population. All the patients received standard protocol based immunosuppression in addition to supportive care. Immune-complex glomerulonephritis (ICGN) was the most common etiology (n = 31; 77.5%) followed by pauci-immune glomerulonephritis (PauciGN; n = 8; 20%) and anti-glomerular basement membrane disease (n = 1; 2.5%). The most common etiology of ICGN was IgA nephropathy (n = 11; 27.5%) followed by lupus nephritis (n = 7; 17.5%) and post-infectious glomerulonephritis (PIGN) (n = 7; 17.5%). The patients with PauciGN were significantly older compared to those with ICGN (44.5 ± 15 years vs. 31.8 ± 11 years; P = 0.01). The patients with PauciGN presented with significantly higher serum creatinine (9.7 ± 4.4 vs. 6.6 ± 3.3 mg/dl; P = 0.03). The histopathologic parameters of ICGN and PauciGN were comparable except for a higher proportion of sclerosed glomeruli in ICGN. At the end of 3 months follow-up, only two patients went into complete remission (5.4%). Majority of the patients had end-stage renal failure (48.6%) and were dialysis dependent and seven patients (18.9%) expired. There was no signifi difference in the renal survival (10.9 ± 1.9 vs. 9.6 ± 3.3 months) or patient survival (17.5 ± 2.1 vs. 17.3 ± 4.3 months). The parameters associated with adverse outcomes at 3 months were hypertension (odds ratio [OR]: 0.58; confidence interval [CI]: 0.36–0.94), need for renal replacement therapy (OR: 0.19; CI: 0.04–0.9), serum creatinine at admission (P = 0.019), estimated glomerular filtration rate (P = 0.022) and percentage of fibrocellular crescents (P = 0.022).

Glomerulonephritis – Do We Have Promising Role of Monoclonal Antibodies?

In present era, drugs like steroids, cytotoxic drugs and calcineurin inhibitors are the backbone to treat immune mediated glomerular diseases. Failure of these therapies often results in persistence of proteinuria, refractory illness and later chronic kidney diseases. The quests to find an answer to such diseases have resulted in the introduction of monoclonal antibodies or target specific drugs. Rituximab is the first monoclonal antibody, which was studied extensively in pauci-immune glomerulonephritis and is now approved for its role in refractory and new onset renal vasculitis. Belimumab has shown role in active systemic lupus erythematous (SLE). With increasing insight in glomerular pathophysiology, many new monoclonal antibodies are now being under trial. Their encouraging results allowed further research on target cytokines, inflammatory mediators and different lymphocyte populations. This review shall discuss monoclonal and their emerging role in glomerulonephritis.

RECURRENT ANCA-ASSOCIATED VASCULITIS AFTER KIDNEY ALLOTRANSPLANTATION

The paper describes a clinical case of recurrent microscopic polyangiitis diagnosed 10 years after kidney allotransplantation that was accompanied by the hyperproduction of antibodies to myeloperoxidase, graft damage with the morphological picture of pauci-immune extracapillary glomerulonephritis with crescents and other systemic manifestations, including interstitial lung injury complicated by hemoptysis. An effect is produced by biological anti-B-cell therapy with rituximab. The discussion involves the detailed review of the literature.

Pauci-Immune Crescentic Glomerulonephritis in Connective Tissue Disease.

Pauci-immune crescentic glomerulonephritis is commonly seen in ANCA-associated vasculitis but it is rarely seen during the course of other connective tissue diseases like lupus or Sjogren's syndrome or MCTD. We report 3 cases of pauci-immune crescentic glomerulonephritis in patients with connective tissue disease other than vasculitis. We reviewed literature and made summary of previously reported cases of this rare entity. Clinical and laboratory features of these patients varied widely, but most of patients have met criteria for lupus. In this small population of patients there is no correlation with ANCAs. Most of the patients were treated with aggressive immunosuppression and did well if they were treated early in the course of their disease. One of our patients required renal transplant, but she presented late in the course of her disease, as evidenced by chronicity on her renal biopsy. Whether these patients are overlap of vasculitis and other connective tissue diseases or to be considered as a separate entity is yet to be described. Clinicians must be aware of these presentations because initial presentation can be severe.

Eosinophilic Granulomatous Polyangitis with Renal Granulomatous Angitis and Interstitial Eosinophilic Infiltration without Lung Granuloma

Eosinophilic granulomatous with polyangiitis (EGPA) is systemic vasculitis characterized by concomitant symptoms of asthma, allergic rhinitis, and marked increase in peripheral eosinophilia. It was previously known as Churg-Strauss syndrome. EGPA incidence in Japan is very low, with only approximately 1,800 cases reported. Renal involvement occurs in approximately 20-25% of EGPA patients, and the most typical expression is pauciimmune crescentic glomerulonephritis. We herein report a case of 69-year-old Japanese woman with fever and high titer of myeloperoxidase-antineutrophil cytoplasmic antibodies (MPO-ANCA) and eosinophilia. Her renal biopsy showed massive interstitial nephritis with granulomatous vasculitis like lesion without apparent active crescent formation in glomeruli. Immediately after steroid treatment (prednisolone [PSL] 30 mg/day), she had symptomatic relief and was discharged with a reduction in MPO-ANCA.

Necrotizing and crescentic glomerulonephritis with membranous nephropathy in a patient exposed to levamisole-adulterated cocaine.

Levamisole is an antihelminthic agent widely used as an adulterant of illicit cocaine recently implicated as a cause of antineutrophil cytoplasmic antibody (ANCA)–associated microscopic polyangiitis in cocaine abusers. An isolated case of membranous nephropathy (MN) associated with levamisole exposure has also been reported. We report the first case, to our knowledge, of a patient with both microscopic polyangiitis manifest as a pauci-immune necrotizing and crescentic glomerulonephritis and concurrent MN in the setting of chronic cocaine abuse and presumed levamisole exposure, raising the hypothesis that levamisole was the causative agent in the development of this rare dual glomerulopathy.

Spotlight on rituximab in the treatment of antineutrophil cytoplasmic antibody-associated vasculitis: current perspectives

A 54-year-old patient presented to his general practitioner because of strong muscle pain in both thighs. Inflammatory parameters (CRP 16.3 mg/dL) and white blood cells (15 g/L) were elevated. The patient reported a weight loss of 10 kg in 4 weeks. There was no fever or any other specific symptoms. Urine dipstick examination and computed tomography of the chest were unremarkable. Because of increasing symptoms, the patient was referred to our department. Magnetic resonance tomography showed diffuse inflammatory changes of the muscles of both thighs. Neurological examination and electrophysiology revealed axonal sensorimotor neuropathy and ground-glass opacities of both lungs had occurred. Serum creatinine increased to 229 μmol/L within a few days, with proteinuria of 3.3 g/g creatinine. Kidney biopsy showed diffuse pauci-immune proliferative glomerulonephritis. Proteinase 3-specific antineutrophil cytoplasmic antibodies were markedly increased. Birmingham Vasculitis Activity Score was 35. Within 2 days, serum creatinine further increased to 495 μmol/L. Plasma exchange, high-dose glucocorticosteroids, and hemodialysis were started. The patient received cyclophosphamide 1 g twice and rituximab 375 mg/m2 four times according to the RITUXVAS protocol. Despite ongoing therapy, hemodialysis could not be withdrawn and had to be continued over 3 weeks until diuresis normalized. Glucocorticosteroids were tapered to 20 mg after 2 months, and serum creatinine was 133 μmol/L. However, nephritic urinary sediment reappeared. Another dose of 1 g cyclophosphamide was given, and glucocorticosteroids were raised for another 4 weeks. After 6 months, the daily prednisolone dose was able to be tapered to 5 mg. Serum creatinine was 124 μmol/L, proteinuria further decreased to 382 mg/g creatinine, and the Birmingham Vasculitis Activity Score was 0. Maintenance therapy with rituximab 375 mg/m2 every 6 months was started. At the last visit after 8 months, the patient was still in remission, with only minor persistent dysesthesia of the left foot and a persistent serum creatinine of 133 μmol/L.

A historical study of American patients with anti-neutrophil cytoplasmic antibody negative pauci-immune glomerulonephritis.

Anti-neutrophil cytoplasmic antibodies (ANCA) play an important role in the pathogenesis of ANCA-associated vasculitis. The lack of ANCA antibodies may indicate a variation in clinical presentation and outcomes of this disease. We identified 74 adult patients between 1995 and 2009 with the diagnosis of pauci-immune glomerulonephritis. Demographics, histological features, and treatment outcomes were compared between ANCA-positive and ANCA-negative patients. These factors were correlated with renal function at presentation and follow-up. Of the 74 patients, 57 were ANCA-positive, and 17 were ANCA-negative. Demographics and mean Birmingham Vasculitis Activity Score were similar between ANCA-negative and ANCA-positive patients at presentation. Renal function was significantly worse at presentation in the ANCA-negative patients (eGFR 16.59 vs. 31.89ml/min/1.73m(2), p = 0.03). Patients in the ANCA-negative group had a significantly higher interstitial fibrosis score compared to the ANCA-positive group (2.1 vs.1.6, p = 0.04). The median time to remission was shorter in the ANCA-negative patients (51 vs. 78days, p = 0.01). Long-term renal function and 1-year patient and renal survival were similar between ANCA-negative and ANCA-positive patients. Baseline eGFR, percentage of normal glomeruli, glomerular sclerosis, and tubulointerstitial scarring predicted eGFR at 1year in both groups similarly. This is the first historical review of American patients with pauci-immune glomerulonephritis, comparing patients with ANCA-negative and ANCA-positive serology. Although ANCA-negative patients present with lower eGFR and more interstitial fibrosis, 1-year and long-term outcomes in both groups are similar.