Systemic lupus erythematosus associated with ANCA-associated vasculitis: an overlapping syndrome?

Overlapping systemic lupus erythematosus, seropositive erosive rheumatoid arthritis, and ANCA-associated vasculitis: A case report and literature review

The overlap of rheumatoid arthritis and systemic lupus erythematosus is well described, with a syndrome known as 'rhupus'. ANCA-associated vasculitis, however, is uncommonly associated with other autoimmune conditions. Here, we present a case of lupus, rheumatoid arthritis, and ANCA-associated vasculitis, with significant time elapsed between presentations, resulting in an accumulation of the three diagnoses over the course of 35 years. The patient was diagnosed with lupus at age 45, presenting with inflammatory polyarthritis, thrombocytopenia, leukopenia, positive ANA, positive anti-DNA, and hypocomplementemia. She was maintained on hydroxychloroquine therapy with minimal disease activity. Approximately 20 years later, she had a flare of polyarthritis with bilateral wrist erosive arthropathy and a positive rheumatoid factor, diagnosed as rheumatoid arthritis. Anti-TNFα therapy was initiated, and she was stable for a further 10 years. At age 79, she developed ANCA-associated vasculitis AAV with pulmonary and renal manifestations, treated with rituximab induction therapy and steroids. She recovered and her MPO-ANCA titre normalised. One year later, off the anti-TNFα, she again experienced an acute kidney injury with a repeat rise in MPO-ANCA. She was re-induced and maintained on steroids and rituximab. This novel case highlights the range of possible overlap syndromes, as well as how multiple autoimmune diagnoses can evolve over decades in previously stable disease. There is growing work around polyautoimmunity with ANCA-associated vasculitis and other systemic autoimmune diseases, which has potential to identify common aetiologies and pathogenesis. Knowledge of these overlap syndromes can help to recognise and manage these conditions in a timely manner.

Systemic lupus erythematosus and antineutrocytic cytoplasmic antibody-associated vasculitis overlap syndrome presenting mainly with alveolar hemorrhage: A case report and literature review

RATIONALE

Systemic lupus erythematosus (SLE) and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are 2 different diseases that can manifest in the same person, which are known as SLE/AAV overlap syndrome. This overlap syndrome is difficult to diagnose, a high rate of missed diagnosis and misdiagnosis, and a poor prognosis.

PATIENT CONCERNS

A 52-year-old woman was diagnosed with SLE in 2019. She was readmitted to our hospital in October 2021 because of abdominal pain and melasma for 10 days.

DIAGNOSES

She had positive anti-dsDNA, decreased complement C3 and C4, fever, polyarthralgia, and hemolytic anemia. She was diagnosed as microscopic polyangiitis according to the American College of Rheumatology 2022 AAV classification criteria (she had 4 items: no nasal lesions, eosinophils < 1 × 109, negative c/PR3-ANCA antibodies, and positive p-ANCA antibodies. The score was 6 points).

INTERVENTIONS

The patient was treated with methylprednisolone 200 mg and cyclophosphamide 0.2 g immunosuppressive therapy.

OUTCOMES

After 2 months of follow-up, the patient's symptoms, including abdominal pain, melena, hematuria, and hemoptysis, resolved completely. And she underwent a reexamination of chest computed tomography and the results showed the previous exudation had been absorbed.

LESSONS

AAV should be considered in lupus patients with the above symptoms, especially the progressive decrease of hemoglobin. Relevant examinations are needed to confirm the diagnosis. Early diagnosis and accurate treatment of SLE/AAV overlap syndrome are beneficial to patients' better prognosis and control the treatment cost.

Rare case of exostosin 1/exostosin 2-related membranous lupus nephritis concomitant with dual ANCA- and anti-GBM antibody-associated crescentic glomerulonephritis effectively diagnosed by mass spectrometry: a case report

BACKGROUND

Recent developments in mass spectrometry (MS) have revealed target antigens for membranous nephropathy (MN), including phospholipase A2 receptor and exostosin 1/exostosin 2 (EXT1/2). EXT1/2 are known antigens of autoimmune disease-related MN, especially membranous lupus nephritis. We describe the case of an elderly man who developed nephrotic syndrome followed by progressive renal dysfunction.

CASE PRESENTATION

A 78-year-old man presented with rapidly progressive renal dysfunction with proteinuria and hematuria. Three years previously, he had developed leg edema but did not receive any treatment. Laboratory tests showed elevated anti-nuclear antibody (Ab), anti-dsDNA Ab titer, and hypocomplementemia, indicating systemic lupus erythematous. Myeloperoxidase anti-neutrophil cytoplasmic Ab (ANCA) and anti-glomerular basement membrane (GBM) Ab were also detected. The renal pathologic findings were compatible with crescentic glomerulonephritis (GN), whereas non-crescentic glomeruli exhibited MN without remarkable endocapillary or mesangial proliferative change. Immunofluorescence microscopy revealed glomerular IgG, C3, and C1q deposition. All IgG subclasses were positive in glomeruli. Anti-PLA2R Ab in serum was negative. MS analysis was performed to detect the antigens of MN, and EXT1/2 was detected in glomeruli. Therefore, we reached a diagnosis of membranous lupus nephritis concurrent with both ANCA-associated vasculitis and anti-GBM-GN. The simultaneous occurrence of these three diseases is extremely rare.

CONCLUSIONS

This is the first report of EXT1/2-related membranous lupus nephritis concurrent with ANCA-associated vasculitis and anti-GBM-GN. This case demonstrates the usefulness of MS in diagnosing complicated cases of MN.

Subarachnoid Hemorrhage in Autoimmune Vasculitis: A Rare Presentation of Systemic Lupus Erythematosus-Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis Overlap Syndrome

Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) and systemic lupus erythematosus (SLE), though they share similar clinical characteristics, are distinguishable based on specific characteristics. The concomitant presentation of SLE and AAV as overlap syndrome is rare and makes the diagnosis challenging. Here, we describe a rare case of SLE and AAV overlaps presenting with hemorrhagic stroke as initial presentation, which has been reported only once before. The presence of several positive autoantibodies made the diagnosis challenging, but a kidney biopsy provided the definitive diagnosis and aided in initiating immunosuppressive therapy. The patient did not respond to standard initial surgical measures to lower elevated intracranial pressure and showed significant improvement to immunosuppressive therapy proving the temporal relationship. The authors of this case study aim to highlight the importance of considering SLE-AAV overlap in patients presenting with features similar to those described in the case report and intervening early, as delays in diagnosis can be fatal.

A Prospective Follow-Up Study on the Disease Course and Predictors of Poor Outcomes in a Random Population-Based Cohort of Newly Diagnosed Lupus Patients

Background and objective

Systemic lupus erythematosus (SLE) is one of the most devastating systemic autoimmune connective tissue diseases. There is a paucity of prospective data on Pakistani SLE patients, and in this prospective study, we aimed to investigate the disease course, clinical outcomes, and the predictors of poor outcomes in a random population-based cohort of newly diagnosed SLE patients (diagnosed within the last one year).

Methods

This was a prospective observational study carried out in the rheumatology department of the Fatima Memorial Hospital, Lahore. Lupus patients are regularly reviewed in our dedicated lupus clinic every one to three months. For the purpose of this study, a focus group of newly diagnosed patients (diagnosed within the last one year) attending our lupus clinic was identified and prospectively followed up for 12 months. A wide range of demographical and clinical parameters was recorded. The association of clinical variables with the progressive disease was determined using univariate and multivariate logistic regressions.

Results

Prospective data of 89 newly diagnosed SLE patients regularly attending our dedicated lupus clinic were reviewed. During the study period, (January 2021 through January 2022), these patients had multiple visits overall - median: five, minimum: three, and maximum: nine visits [interquartile range (IQR) 4-7]. All 89 patients had completed one year of follow-up. Of note, 46% of the cohort was noted to have an ongoing active disease during the majority of visits in the study period. On multiple logistic regression analysis, there was a significant association between ongoing active disease ("progressors") and low education status [odds ratio (OR): 2.81, 95% confidence interval (CI): 1.01-7.76, p=0.046], stress at home (OR: 5.8, 95% CI: 2.13-15.8, p=0.001), and hematologic manifestations (OR: 3.0, 95% CI: 1.08-8.32, p=0.03).

Conclusions

Almost half of our cohort of lupus patients demonstrated active disease manifestations throughout the one-year prospective follow-up, and these were found to be associated with low education status, stress at home, and hematological manifestations.

Systemic lupus erythematosus/ANCA-associated vasculitis overlap: An explanation for atypical lupus manifestation

The coexistence of systemic lupus erythematosus (SLE) and ANCA-associated vasculitis (AAV) as an overlapping syndrome is not common. Here, we report a case of a 33-year-old woman, with recent SLE diagnosis due to skin, kidney, articular, and immunologic compromise, in whom a chest CT scan showed bilateral nodules, consolidations, and tree-in-bud pattern; thoracoscopic lung biopsy revealed diffuse non-caseating granulomas, without other features of sarcoid, organizing pneumonia, or hypersensitivity pneumonitis with high positive p-ANCA titers. Overlap between SLE and AAV was a possible explanation for lupus granulomatous pneumonitis, and for this reason, a multidisciplinary meeting was held to evaluate complex patients with interstitial lung diseases patients.

Gene polymorphisms in ULK1 and PIK3CA are associated with the risk of microscopic polyangiitis in the Guangxi Zhuang Autonomous Region in China

Background

Microscopic polyangiitis (MPA) is a systemic autoimmune disease characterized by inflammation of small- and medium-sized blood vessels. Autophagy-related protein polymorphisms are involved in autoimmune disease. The aim of this study was to evaluate the effects of single-nucleotide polymorphisms (SNPs) in the ULK1 and PIK3CA genes on the risk of MPA.

Method

A total of 208 patients with MPA and 211 controls in the Guangxi Zhuang Autonomous Region were recruited and analyzed. The SNPs selected were detected by polymerase chain reaction and high-throughput sequencing. The differences in allele and genotype frequency, various genetic models, and stratification analyses were evaluated, haplotype evaluation was performed after linkage disequilibrium analysis, and the interaction between gene alleles was analyzed.

Results

A statistically significant difference was detected in the genotypic distribution of two SNPs between the two groups: ULK1rs4964879 (p = 0.019) and PIK3CArs1607237 (p = 0.002). The results of the genetic models revealed that ULK1rs4964879 and rs9481 were statistically significantly associated with an increased risk of MPA, whereas PIK3CArs1607237 was associated with a reduced risk. The association between SNPs and MPA risk was affected by age, sex, and ethnicity. The ULK1 haplotype (G-T-A-C-G-A) and PIK3CA haplotype (T-G) were associated with a reduced risk of MPA, while the PIK3CA haplotype (C-G) was associated with an increased risk.

Conclusion

In this study, polymorphisms in the autophagy-related genes ULK1 and PIK3CA and their association with MPA were examined. The results showed that the polymorphisms in ULK1 (rs4964879 and rs9481) and PIK3CA (rs1607237) were significantly associated with MPA risk in the Guangxi population. However, the molecular mechanisms are still unclear; basic science research and studies with larger samples are needed to confirm our conclusions and explore the underlying mechanisms.

A Case of Systemic Lupus Erythematosus and Antineutrophil Cytoplasmic Antibodies-Associated Vasculitis Overlap Syndrome

An overlap of systemic lupus erythematosus (SLE) and antineutrophil cytoplasmic antibodies- (ANCA-) associated vasculitis (AAV) is extremely rare: approximately 40 cases have been reported to date. A literature review indicates that they are more common in women in their forties, and simultaneous onset has been reported in 69% of cases. In addition, both lupus nephritis and ANCA-associated glomerulonephritis were observed on renal biopsy. This report presents the case of a 35-year-old woman with an 8-month history of polyarthralgia who was admitted to our hospital. She was diagnosed with SLE due to typical clinical presentation of the disease: polyarthritis, lymphocytopenia, hypocomplementemia, presence of antinuclear and anti-dsDNA antibodies, and proteinuria. However, purpura were scattered, and the titer of antimyeloperoxidase-antineutrophil cytoplasmic antibodies (MPO-ANCA) was high. A skin biopsy revealed leukocytoclastic vasculitis that involved poor immune complex deposition. A renal biopsy showed necrotizing glomerulonephritis with cellular and fibrocellular crescent formation that involved deposition of IgM and C3c only in the mesangial area and the peripheral capillaries. Additionally, no electron-dense deposits were observed under electron microscopy. These pathological findings were consistent with AAV rather than with SLE. Therefore, we finally diagnosed the patient with both SLE and microscopic polyangiitis. After treatment with methylprednisolone and intravenous cyclophosphamide pulse therapies, renal function improved and MPO-ANCA levels decreased. In cases of suspected overlap between SLE and AAV, appropriate diagnosis and treatment are important.

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 antibody-associated 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 biopsy-proven 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, hypocom-plementemia, 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 cyclo-phosphamide, 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.

Anca-positive vasculitis with full-house nephropathy, an unusual association: a case report and review of literature

Rapidly progressive glomerulonephritis is a medical emergency, with mortality around 20%. It is characterized by crescent glomerulonephritis and progressive loss of kidney function, hematuria, and proteinuria. Its classification is given by immunofluorescence detection of antibodies against glomerular basement membrane (Anti-MBG), immunocomplexes, or pauci-immune pattern. Its etiology should be based on clinical findings, immunological profile, age, sex, and histopathological characteristics. We present a case of a 27-year-old woman with symptoms consistent with rapidly progressive glomerulonephritis and biopsy findings of a full-house kidney nephropathy, with an early fatal outcome. An association of low incidence, as it is a case with a full-house pattern, and an autoimmune profile for negative systemic lupus erythematosus makes this a rare case. ANCA-associated vasculitis with full-house kidney disease was diagnosed, an unusual condition with up to 3% presentation and few reports in the literature, highlighting the importance of its reporting and contribution to the literature.

A Case of Systemic Lupus Erythematosus/Antineutrophil Cytoplasmic Antibody-Associated Vasculitis Overlap Syndrome with Dissociated Pathological and Immunological Findings

Systemic lupus erythematosus/antineutrophil cytoplasmic antibody-associated vasculitis overlap syndrome (SLE/AAV OS) describes a pathological condition that presents with overlapping features of two diseases. There have been few reports of SLE/AAV OS and none from Japan. We present the case of a 59-year-old woman admitted with chief complaints of fever and decreased renal function. SLE was suspected due to the identification of four items from the diagnostic criteria of the American College of Rheumatology, including positivity for anti-ds-DNA and antinuclear antibodies. However, pathological findings from the kidney biopsy suggested pauci-immune crescentic glomerulonephritis. She was also diagnosed with AAV according to the Chapel Hill Consensus Conference (CHCC) 2012 definitions and the classification algorithm of AAV. SLE/AAV OS was suspected, we started immunosuppressant therapy, and subsequently her renal function improved. In previous reports, initial immunological and pathological findings generally concur. In cases where clinical and pathological features appear to conflict, as in the present case, a treatment strategy decision should be based on pathological and immunological findings to improve the prognosis of OS.

Systemic Lupus Erythematosus (SLE) with Acute Nephritis, Antineutrophil Cytoplasmic Antibody- (ANCA-) Associated Vasculitis, and Thrombotic Thrombocytopenic Purpura (TTP): A Rare Case Report with Literature Review

Thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disorder that requires urgent identification and treatment. The association of TTP with systemic lupus erythematosus (SLE) and vasculitis has been reported, however, never simultaneously. A 33-year-old woman with a history of SLE presented with acute abdominal pain, fever, arthralgias, and skin rash. She had acute severe hypertension, diffuse abdominal tenderness, and petechial rash. Diagnostic work-up revealed active urine sediment with proteinuria and hematuria and elevated creatinine, anemia, and thrombocytopenia. She was diagnosed with acute lupus nephritis and early microangiopathic hemolytic anemia in the setting of hypertensive urgency and started on intravenous methylprednisolone 500 mg once a day. Within 48 hours, she developed shock with multiorgan dysfunction and succumbed to her illness. Laboratory tests later showed ADAMTS13 activity less than 10% consistent with TTP and p-antineutrophil cytoplasmic antibody (ANCA) positivity. Autopsy revealed small-vessel vasculitis of the visceral organs. Kidney biopsy demonstrated diffuse proliferative glomerulonephritis. This case illustrates the occurrence of SLE nephritis, p-ANCA vasculitis, and severe TTP with rapidly fatal course, and the importance of having a low threshold for initiating plasma exchange therapy. Here, we discuss the case and provide a literature review on cases of TTP with SLE and vasculitis.

Association of NCF1 polymorphism with systemic lupus erythematosus and systemic sclerosis but not with ANCA-associated vasculitis in a Japanese population

Genome-wide association studies of systemic lupus erythematosus (SLE) in Chinese and Korean populations demonstrated strong association of single nucleotide polymorphisms (SNPs) located in the GTF2I-NCF1 region, rs73366469 (GTF2I), rs117026326 (GTF2I), rs80346167(GTF2IRD1) and rs201802880 (NCF1). This region has also been associated with susceptibility to Sjögren syndrome and rheumatoid arthritis; however, association studies with systemic sclerosis (SSc) and ANCA-associated vasculitis (AAV) have not been reported. Here we made an attempt to confirm their associations with SLE in the Japanese population, to find the primarily associated SNP, and to investigate whether these SNPs are also associated with susceptibility to SSc and AAV. By genotyping these four SNPs on 842 SLE, 467 SSc, 477 AAV patients and 934 healthy controls, striking association was confirmed in Japanese SLE. In addition, these SNPs were significantly associated with susceptibility to SSc, but not with AAV. Conditional logistic regression analysis revealed that the association of NCF1 rs201802880, a missense SNP encoding p.Arg90His, can account for the association of other SNPs by linkage disequilibrium. These results suggested that GTF2I-NCF1 region is associated with susceptibility to multiple autoimmune rheumatic diseases but not with AAV, and the primarily associated variant may be the missense SNP in NCF1.

Differences in clinico-pathological characteristics and outcomes between proteinase 3-ANCA positivity and myeloperoxidase-ANCA positivity in lupus nephritis

BACKGROUND

Owing to the low prevalence of anti-neutrophil cytoplasmic antibodies (ANCA) in lupus nephritis (LN), there is no study about the differences between proteinase 3 (PR3)-ANCA positivity and myeloperoxidase (MPO)-ANCA positivity in LN until now.

METHODS

Here we perform a retrospective study to determine whether there are differences in clinic-pathological characteristics and renal outcomes between PR3-ANCA-positive LN patients and MPO-ANCA-positive LN patients.

RESULTS

A total of 26 (27.4%) PR3-ANCA-positive LN patients and 69 (72.6%) MPO-ANCA-positive LN patients (p < 0.001) were eligible for this study. Compared with PR3-ANCA-positive LN patients, MPO-ANCA-positive LN patients had significantly higher levels of serum creatinine (109.6 µmol/l vs. 74.3 µmol/l, p = 0.02), lower titers of antinuclear antibodies (ANA) (128 vs. 256, p = 0.01), and higher serum concentrations of C3 and C4 (0.54 g/l vs. 0.36 g/l, p = 0.002; 0.12 g/l vs. 0.06 g/l, p < 0.001; respectively). Furthermore, the MPO-ANCA-positive group had higher scores for chronicity index (p = 0.007), including interstitial fibrosis (p = 0.001) and tubular atrophy (p = 0.03) on biopsy specimens. The renal survival rates for MPO-ANCA-positive LN patients were 94.1% at 1 year, 83.2% at 5 years and 79.6% at 10 years; these values were worse when compared with those of the PR3-ANCA-positive group, which were 100%, 100% and 100%, respectively.

CONCLUSION

MPO-ANCA-positive LN patients had more severely impaired baseline renal function and less active lupus serology. More severely chronic pathological changes, including interstitial fibrosis and tubular atrophy on renal specimens, occurred in MPO-ANCA-positive LN patients. We found that MPO-ANCA-positive LN patients had worse renal outcomes.

Systemic Lupus Erythematosus (SLE) and Antineutrophil Cytoplasmic Antibody-Associated Vasculitis (AAV) Overlap Syndrome: Case Report and Review of the Literature

We report here the first case of systemic lupus erythematosus (SLE) and antineutrophil cytoplasmic antibody-associated vasculitis overlap syndrome (SLE/AAV) who had granulomatous polyangiitis (GPA) as the initial presentation. SLE/AAV overlap syndrome is an uncommon entity recently described in the literature. Prior reported patients with SLE/AAV overlap syndrome presented with SLE and microscopic polyangiitis (MPA). Our patient initially presented with granulomatous gastric ulcer and later developed respiratory failure. She was diagnosed with GPA. While on maintenance treatment with azathioprine 150 mg/day, she developed hematuria and proteinuria which turned out to be from class V lupus nephritis instead of relapse of vasculitis. Currently, the patient is doing well after treatment with rituximab. Although rare, this entity should be recognized and need to be treated appropriately.

Systemic lupus erythematosus and antineutrophilic cytoplasmic antibody-associated vasculitis overlap syndrome complicated by subarachnoid hemorrhage: case-based review

Systemic lupus erythematosus (SLE) and antineutrophil cytoplasmic antibody-associated vasculitis (AAV) overlap syndrome is an inflammatory disorder with a mixed presentation that is characterized by clinical features of both SLE and AAV. Although renal disease predominates, any organ system in the body may be affected. Neurologic manifestation in patients with SLE-AAV overlap syndrome is rare and has only been previously documented as cerebral ischemia. We report a patient with SLE-AAV overlap syndrome diagnosed based on clinical, serologic and biopsy-proven histologic findings who presented with subarachnoid hemorrhage (SAH) secondary to ruptured right anterior cerebral artery aneurysm. To the authors' knowledge, this is the first reported case of SLE-AAV overlap syndrome diagnosed in a patient with a SAH due to an intracranial aneurysm. Neurologic involvement in patients with SLE-AAV overlap syndrome is uncommon and has not been well-studied. Clinicians who encounter patients with neurologic signs that present with symptoms and a serologic profile that correspond to both SLE and AAV criteria, should consider the association between SLE-AAV overlap syndrome and a hemorrhagic stroke, specifically SAH.

Detection of anti-neutrophil cytoplasmic antibodies in dogs with immune-mediated inflammatory diseases

Anti-neutrophil cytoplasmic antibody (ANCA) is a type of autoantibody against neutrophil cytoplasm. In veterinary medicine, few studies have reported the detection of ANCA in dogs, and most of these studies were performed in dogs with inflammatory bowel disease (IBD). The aim of this study was to evaluate whether ANCA is detected in dogs with immune-mediated inflammatory diseases (IMIDs) other than IBD. Serum samples were collected before treatment initiation from 40 client-owned dogs with various diseases and 22 healthy beagle dogs; the dogs were classified into two groups: IMID group (n = 16) and control group (n = 46). ANCA was detected using the indirect fluorescent antibody test. Of the 16 dogs in the IMID group, 13 (81.3%) tested positive for ANCA. In contrast, of the 46 dogs in the control group, 13 (28.03%) tested positive for ANCA. Moreover, a significant association between ANCA positivity and IMIDs was identified in the IMID group than in the control group (P = 0.0003). In the control group, however, dogs with bacterial infection showed a relatively high rate of ANCA positivity. Therefore, ANCA positivity was observed in dogs with both IMIDs and bacterial infection. This suggested that ANCA positivity is associated with diseases accompanied by neutrophil activation and infiltration.

Complement 3 glomerulonephritis in rheumatoid arthritis: A case report and follow-up

Glomerulonephritis (GN) caused by rheumatoid arthritis may manifest as various pathological types; however, to the best of our knowledge, rheumatoid arthritis-associated complement 3 (C3)-GN has not been reported by any previous studies. C3GN is caused by dysregulation of the alternative pathway of complements, which is completely different from activation of the classic pathway of a typical autoimmune disease to cause renal damage. The present study describes a patient with a history of rheumatoid arthritis for 18 years, who presented with edema, proteinuria, hematuria, hypoproteinemia and a hypocomplementemic state. The pathological diagnosis was C3GN based on histological examination of a renal biopsy specimen. Hormone treatment on its own appeared to be effective and achieved complete clinical remission, while the follow-up of the condition remained stable.

Anti-Myeloperoxidase Antibodies Associate with Future Proliferative Lupus Nephritis

Background

The subclinical pathophysiology of proliferative lupus nephritis (PLN) has not been fully elucidated. Myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) is associated with PLN, but prediagnostic levels have not been reported.

Methods

We performed a retrospective case-control Department of Defense Serum Repository (DoDSR) study comparing MPO-ANCA levels in longitudinal prediagnostic serum samples for 23 biopsy confirmed proliferative lupus nephritis (PLN) patients to DoDSR identified age, sex, race, and age of serum matched healthy and SLE without LN disease controls. We also compared the temporal relationship of MPO-ANCA to anti-double stranded DNA antibodies (dsDNAab).

Results

A greater proportion of PLN patients had prediagnostic MPO-ANCA levels above ≥3 U/mL and ≥6 U/mL compared to SLE without LN (91% versus 43%, p < 0.001; 57% versus 5%, p < 0.001, resp.). In subgroup analysis, the MPO-ANCA threshold of ≥3 U/mL was significant at <1 year (88% versus 39%, p = 0.007) and 1-4 years (87% versus 38%, p = 0.009) prior to diagnosis. Statistically significant subclinical MPO-ANCA levels (≥3 U/mL) occurred prior to statistically significant dsDNAab ≥ 3 IU/ml (89% versus 11%, p = 0.003).

Conclusions

Subclinical MPO-ANCA levels could distinguish future PLN from SLE without LN. MPO-ANCA manifests prior to clinical disease and subclinical dsDNAab to suggest that it may contribute directly to PLN pathogenicity.

Sjögren's syndrome manifesting as clinicopathological features of TAFRO syndrome: A case report

RATIONALE

TAFRO syndrome is a newly proposed disorder that manifests as thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. In this report, we describe the development of severe TAFRO syndrome-like systemic symptoms during the clinical course of juvenile-onset Sjögren's syndrome in a 32-year-old woman.

PATIENT CONCERNS

The patient was admitted due to dyspnea, fever, polyarthralgia, and generalized edema. She had been diagnosed with Sjögren's syndrome at the age of 14 years, based on histopathological examination of a biopsy of the minor salivary glands and the development of Raynaud's phenomenon, with no follow-up treatment required. On admission, she presented with anemia, elevated C-reactive protein levels, anasarca, and hepato-splenomegaly. A bone marrow examination revealed increased megakaryocytes with reticulin fibrosis, and the histopathology of an axillary lymph node was consistent with mixed-type Castleman disease. Eventually, she developed thrombocytopenia.

INTERVENTIONS

Her symptoms fulfilled all of the major and minor categories of the diagnostic criteria for TAFRO syndrome. However, considering her prior diagnosis, we assumed that the clinical presentation was consistent with an acute exacerbation of Sjögren's syndrome. Unlike typical cases of TAFRO syndrome, the administration of relatively low-dose prednisolone relieved her symptoms.

LESSONS

Differentiation between TAFRO syndrome and exacerbation of an autoimmune disease is clinically important, although this can be challenging. Identification of specific biomarkers for TAFRO syndrome would be clinically beneficial.

Treatment and clinicopathological characteristics of lupus nephritis with anti-neutrophil cytoplasmic antibody positivity: a case-control study

OBJECTIVE

To assess the clinical features, pathological presentations, treatments and outcomes of lupus nephritis (LN) with anti-neutrophil cytoplasmic antibody (ANCA) positivity.

DESIGN

A case-control study.

METHODS

Patients (n=49) were retrospectively included from Jinling Hospital in China if presenting with biopsy-proven ANCA-positive LN between 1985 and 2008. Clinicopathological characteristics and outcomes were analysed and compared with those of a control group (n=1279). We further compared treatment responses and outcomes of ANCA-positive LN patients based on the treatment issued.

RESULTS

The study included 40 women and 9 men (median age 33 years at biopsy): 38 with myeloperoxidase (MPO)-ANCA, 7 with proteinase 3 (PR3)-ANCA and 4 with double positivity. ANCA-positive LN patients exhibited higher haematuria, serum creatinine levels and systemic lupus erythematosus disease activity index scores. On pathological evaluation, class IV LN was predominant, accounting for 61.22% of cases. Light microscopy revealed significantly higher activity index and chronicity index scores, including cellular crescents, interstitial inflammation, tubular atrophy and interstitial fibrosis. ANCA-positive LN patients receiving mycophenolate mofetil as induction therapy had a higher remission rate and better renal outcomes than those receiving cyclophosphamide. During follow-up, end-stage renal disease developed in seven (14.29%) ANCA-positive LN patients, all of them were MPO-ANCA positive.

CONCLUSIONS

The characteristics of ANCA-positive LN were massive haematuria and advanced renal insufficiency. We observed a higher remission rate and better prognoses when using mycophenolate mofetil than when using cyclophosphamide as induction therapy.

Post-transplant immune complex nephritis in a patient with systemic lupus erythematosus associated with ANCA vasculitis

Nearly 20% of SLE corresponds to the pediatric population, and 75% of them have kidney involvement representing an important etiology of chronic kidney disease. A correlation between SLE and ANCA-associated vasculitis has been identified as an overlapping syndrome. Kidney allograft recurrence is rare in SLE when disease control is achieved and with nowadays immunosuppression treatment. Histologic transformation is unusual, especially when there are negative serologic markers and no immune complex deposition reported in native kidneys. A 17-year-old female with crescentic glomerulonephritis, p-ANCA-positive antibodies with pauci-immune pattern in kidney biopsy develops end-stage renal disease requiring hemodialysis. Deceased donor kidney transplant was performed receiving triple immunosuppression thereafter. Thirteen months later serum creatinine rises without evidence of infection, urinary obstruction, or clinical and serologic disease relapse. Allograft biopsy reports mesangial proliferation and "full-house" immunofluorescence. The role of ANCA in SLE physiopathology is controversial, and its relation with lupus nephritis is also discordant. ANCA could represent an important factor in the heterogeneity of systemic lupus erythematosus and lupus nephritis.

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.

Neutrophils in pediatric autoimmune disease

PURPOSE OF REVIEW

As first immune responders, neutrophils are essential mediators of host defense, and also contribute to chronic pathologic inflammation at the crossroads of innate and adaptive immunity. In this review, we will highlight the current understanding of the role of neutrophils in pediatric rheumatology, with a focus on juvenile idiopathic arthritis (JIA) and lupus.

RECENT FINDINGS

In inflamed tissues, neutrophils extrude neutrophil extracellular traps containing autoantigen that potentially drives lupus and rheumatoid factor-positive JIA. However, the contribution of neutrophil extracellular traps to pathogenesis remains an area of intense investigation. In JIA joints, neutrophils are activated to such an extent that associated circulating levels of S100A proteins may serve as biomarkers, correlating with disease activity, predicting response to treatment and heralding flares. Beyond the effects of 'normal' activation, neutrophils in JIA and lupus display dysregulation in gene expression, subset activation, and apoptosis.

SUMMARY

The role of neutrophils in pediatric rheumatology is an understudied area, but garnering increasing attention. Although clearly implicated in JIA and lupus, the specific contributions of neutrophils to pathogenesis and the use of neutrophil activity surrogates as biomarkers require further study. Clarification of these outstanding issues will have implications for diagnosis and treatment of pediatric rheumatologic conditions.

Lupus nephritis: When and how often to biopsy and what does it mean?

Renal disease is a frequent complication of SLE which can lead to significant illness and even death. Today, a baseline renal biopsy is highly recommended for all subjects with evidence of lupus nephritis. Biopsy allows the clinician to recognize and classify different forms of autoimmune lupus glomerulonephritis, and to detect other glomerular diseases with variable pathogenesis which are not directly related to autoimmune reactivity, such as lupus podocytopathy. Moreover, not only glomerular diseases, but other severe forms of renal involvement, such as tubulo-interstitial nephritis or thrombotic microangiopathy may be detected by biopsy in lupus patients. Thus, an accurate definition of the nature and severity of renal involvement is mandatory to assess the possible risk of progression and to establish an appropriate treatment. The indications to repeat biopsy are more controversial. Some physicians recommend protocol biopsies to recognize the possible transformation from one class to another one, or to identify silent progression of renal disease, others feel that good clinical monitoring is sufficient to assess prognosis and to make therapeutic decisions. At any rate, although any decision should always be taken by considering the clinical conditions of the patient, there are no doubts that repeat renal biopsy may represent a useful tool in difficult cases to evaluate the response to therapy, to modulate the intensity of treatment, and to predict the long-term renal outcome both in quiescent lupus and in flares of activity.

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.

"The NET Outcome": Are Neutrophil Extracellular Traps of Any Relevance to the Pathophysiology of Autoimmune Disorders in Childhood?

Neutrophil extracellular trap (NET) formation represents a form of cell death distinct from apoptosis or necrosis, by which invading pathogens are simultaneously entangled and potentially eliminated. Increased NET formation is observed in systemic lupus erythematosus (SLE), rheumatoid arthritis, antineutrophil cytoplasmic antibody-associated small vessel vasculitis, antiphospholipid antibody syndrome (APS), and psoriasis. NETs contribute to the pathogenesis of autoimmunity by exposing cryptic autoepitopes, which may facilitate the generation of autoantibodies, induce the production of interferons, and activate the complement cascade. In SLE, augmented disease activity and renal disease are associated with increased NET formation, so that NETs could serve as a marker for the monitoring of disease activity. NETs can additionally cause endothelial cell damage and death and stimulate inflammation in atheromatous plaques, adding to the accelerated atherosclerosis witnessed in autoimmune disease. Since NETs induce production of interferons, assessing the extent of NET formation might facilitate the prediction of IFN-alpha levels and identification of SLE patients with presumably better responses to anti-IFN-alpha therapies or other novel therapeutic concepts, such as N-acetyl-cysteine and inhibitors of DNase 1 and peptidylarginine deiminase 4 (PAD4), which also target NETs. In summary, the study of NETs provides a novel approach to the understanding of autoimmune disease pathogenesis in childhood and opens new vistas in the development of sensitive disease markers and targeted therapies.

Clinicopathologic Characteristics and Outcomes of Lupus Nephritis With Antineutrophil Cytoplasmic Antibody: A Retrospective Study

Few studies have analyzed the clinicopathologic characteristics and outcomes of lupus nephritis (LN) patients with antineutrophil cytoplasmic antibody (ANCA). The clinical and renal histopathologic data of 154 patients with biopsy-proven LN from 2011 to 2013 were analyzed retrospectively. The patients were followed up for a median period of 16.8 ± 9.4 months, and their outcomes were analyzed. Multivariate Cox analysis was used to evaluate the independent factors for poor outcomes. Among the 154 LN patients, 26 (16.88%) were seropositive for ANCA. The incidences of alopecia, oral ulcer, photosensitivity and skin lesion, and psychosomatic manifestations in the ANCA-positive group were significantly higher than in the ANCA-negative group (P = 0.007, 0.02, 0.02, and 0.03, respectively). Compared with the ANCA-negative group, the ANCA-positive group had significantly lower levels of complement C3 (P = 0.03). Additionally, the positive rate of antinucleosome antibodies, antihistone antibodies, antimitochondrial antibody M2, and anticardiolipin antibodies were higher significantly in the ANCA-positive patients than in the ANCA-negative patients (P = 0.001, 0.001, 0.03, 0.005, respectively). The ANCA-positive group had a notably higher chronic index than the ANCA-negative group (P = 0.01). During the follow-up, the complete remission rate in the ANCA-negative group was higher than that in the ANCA-positive group (P = 0.01). The cumulative renal survival rate in the ANCA-positive group was significantly lower than in the ANCA-negative group (log-rank = 6.59, P = 0.01). Multivariate Cox analysis revealed that the reduced estimated glomerular filtration rate (HR, 1.02; 95% confidence interval, 1.01 to 1.03; P = 0.005), NLR (HR, 1.20; 95% confidence interval, 1.02 to 1.40; P = 0.03), and ANCA (HR, 3.37; 95% confidence interval, 1.12 to 10.09; P = 0.03) were independent risk factors for patients' renal survival after adjusting for age, sex, crescent formation, and glomerulosclerosis. The study found ANCA in LN patients is not rare, and patients with ANCA present with more severe clinicopathologic injuries. Thus, ANCA is an independent risk factor for poor renal outcomes in LN patients.

Pauci-Immune Necrotizing and Crescentic Glomerulonephritis with Membranous Lupus Nephritis, Fifteen Years after Initial Diagnosis of Secondary Membranous Nephropathy

Renal involvement in systemic lupus erythematosus (SLE) is usually immune complex mediated and may have multiple different presentations. Pauci-immune necrotizing and crescentic glomerulonephritis (NCGN) refers to extensive glomerular inflammation with few or no immune deposits that may result in rapid decline in renal function. We report a case of a 79-year-old Hispanic male with a history of secondary membranous nephropathy (diagnosed by renal biopsy 15 years previously) who was admitted with acute kidney injury and active urinary sediment. P-ANCA titers and anti-myeloperoxidase antibodies were positive. The renal biopsy was diagnostic for NCGN superimposed on a secondary membranous nephropathy. A previous diagnosis of SLE based on American College of Rheumatology criteria was discovered via Veteran's Administration records review after the completion of treatment for pauci-immune NCGN. ANCAs are detected in 20–31% of patients with SLE. There may be an association between SLE and ANCA seropositivity. In patients with lupus nephritis and biopsy findings of necrotizing and crescentic glomerulonephritis, without significant immune complex deposition, ANCA testing should be performed. In patients with secondary membranous nephropathy SLE should be excluded.

Diffuse alveolar hemorrhage emerging one week after starting high-dose corticosteroid therapy for granulomatosis with polyangiitis (GPA) with systemic lupus erythematosus (SLE)

A 69-year-old man was diagnosed with granulomatosis with polyangiitis (GPA) based on the presence of skin granuloma, refractory otitis media, renal insufficiency and myeloperoxidase-antineutrophil cytoplasmic antibody positivity and slight lung opacity. He was treated with high-dose corticosteroid therapy. Despite the initial improvement of his renal function and a decrease in his C-reactive protein level, he suffered from an alveolar hemorrhage one week after the start of corticosteroid therapy. An anti-dsDNA antibody test was positive and the patient had hypocomplementemia. Elements of both GPA and systemic lupus erythematosus were thought to have affected his clinical course.

Pathogenesis of antineutrophil cytoplasmic autoantibody-mediated disease

Antineutrophil cytoplasmic autoantibodies (ANCAs) are the probable cause of a distinct form of vasculitis that can be accompanied by necrotizing granulomatosis. Clinical and experimental evidence supports a pathogenesis that is driven by ANCA-induced activation of neutrophils and monocytes, producing destructive necrotizing vascular and extravascular inflammation. Pathogenic ANCAs can originate from precursor natural autoantibodies. Pathogenic transformation might be initiated by commensal or pathogenic microbes, legal or illegal drugs, exogenous or endogenous autoantigen complementary peptides, or dysregulated autoantigen expression. The ANCA autoimmune response is facilitated by insufficient T-cell and B-cell regulation. A putative pathogenic mechanism for vascular inflammation begins with ANCA-induced activation of primed neutrophils and monocytes leading to activation of the alternative complement pathway, which sets in motion an inflammatory amplification loop in the vessel wall that attracts and activates neutrophils with resultant respiratory burst, degranulation, extrusion of neutrophil extracellular traps, apoptosis and necrosis. The pathogenesis of extravascular granulomatosis is less clear, but a feasible scenario proposes that a prodromal infectious or allergic condition positions primed neutrophils in extravascular tissue in which they can be activated by ANCAs in interstitial fluid to produce extravascular necrotizing injury that would initiate an innate granulomatous inflammatory response to wall off the necrotic debris.

Clinical significance of detection of anti-neutrophil cytoplasmic antibodies in patients with autoimmune hepatitis

AIM: To explore the significance of detection of anti-myeloperoxidase antibody (ANCAs) in the diagnosis of autoimmune hepatitis (AIH).

METHODS: In total, 48 AIH patients, 190 non-AIH patients and 50 healthy volunteers were included in this retrospective study. Enzyme-linked immunosorbent assay (ELISA) was used to detect anti-RP3, anti -MPO and ALA, while indirect immunofluorescence (IIF) was employed to detect ANCAs.

RESULTS: The positive rates of ANCA, p-ANCA, x-ANCA and ALA in the AIH group had significant differences compared with the non-AIH group (except for PSC). The positive rate of anti-MPO was significantly higher in the AIH group than in the non-AIH group (P < 0.01). Of all specimens in the AIH group, only 1 was positive for c-ANCA and PR3 simultaneously. There was a good correlation between anti-MPO and ANCA, between anti-MPO and p-ANCA, and between ALA and x-ANCA in the AIH group. The kappa values of anti-MPO and ANCA as well as anti-MPO and p-ANCA were 0.819 and 0.875, respectively, showing excellent agreement.

CONCLUSION: Combined detection of ANCAs is helpful for the diagnosis of AIH and AIH subtypes.