Positive ANCA Research Articles

Vasculitis associated with VEXAS syndrome.

To define the prevalence, distribution, and characteristics of patients with VEXAS who have confirmed vasculitis. Patients with VEXAS syndrome, verified by positive UBA1 mutation, were included. Chart review was performed to identify. characteristics and outcomes. Vasculitis diagnosis was based on either histopathology showing vascular inflammation or non-invasive angiography findings. Summary statistics were calculated. Eighty-nine patients met inclusion criteria. All were male with a median age of onset of 66.9 years (IQR 60.1, 72.7). Median (IQR) follow up was 3.8(2.2-5.5) years during which 21 patients (23.6%) had evidence of vasculitis. Vasculitis subtypes included small vessel vasculitis (19.1%), cutaneous medium vessel vasculitis (2.2%), and large vessel vasculitis (2.2%). No patient had more than one vessel size involved. Histopathology in small vessel vasculitis patients was consistent with cutaneous leukocytoclastic vasculitis in the majority, though one patient had leukocytoclastic peritubular capillaritis on renal biopsy. Cranial symptoms (headache, vision changes, or jaw pain) were noted in 18.0%. Two additional patients not experiencing cranial symptoms exhibited large vessel involvement with confirmed carotid thickening on non-invasive angiography; one of these had a positive temporal artery biopsy. VEXAS syndrome manifests as a variable vessel vasculitis in a quarter of patients, with cutaneous small and medium vessel involvement being particularly common. Some patients may have positive ANCA serologies or even renal vasculitis leading to misdiagnosis. Cranial symptoms are common and may mimic giant cell arteritis, though documented large vessel inflammation is rare.

B-074 Comparative Evaluation of Clinical Utility between Indirect Immunofluorescence and Immunoassay Methods for Antineutrophil Cytopalsmic Antibody Detection

Abstract Background ANCA testing is essential for the diagnosis of vasculitis, commonly using indirect immunofluorescence(IIF) and immunoassay(IA) methods. Recent guidelines recommend IA as the primary test for suspected GPA and MPA, but actual practice varies among physicians. Here, we retrospectively analyzed ANCA test results, focusing on new cases of ANCA-associated vasculitis, and compared the utility of IIF and IA to guide appropriate test selection. Methods From January 2022 to July 2023, 24 new cases of ANCA-associated vasculitis were diagnosed. We checked whether ANCA testing was performed and the results, and compared the turnaround time(TAT) and costs. IIF ANCA tests were performed on a computer-based automated instrument(Helios), and IA ANCA tests were performed on automated instruments(Alegria, Phadia 250) with MPO antigen and PR3 antigen tested simultaneously in a bundled prescription. Results Among the 24 cases, there were 6 GPA, 7 MPA, 7 EGPA, and 4 ANCA-associated GN, with varying diagnostic sensitivities. GPA and EGPA had different ANCA positivity rates than previously reported, suggesting potential ethnic variations in ANCA expression and positivity rates. The test sequence and results, summarized in Table 1, showed 21 out of 22 cases had identical concordance between methods, with an excellent concordance rate (kappa value=0.83). TAT for IIF was 3,452 minutes, and for IA was 1,491 minutes for the whole period, but IA TAT increased to 2,748 minutes after implementing a days-of-the-week testing system. Test costs, with a relative value score of 118.99 for IIF and 156.05 for IA, indicated IA cost approximately 2.6 times higher, considering the bundled prescription of both antigens for IA ANCA testing. Conclusions Evaluating the utility of both methods for ANCA detection, our study highlights high inter-method agreement in ANCA-associated vasculitis. Considering overall cost and turnaround time, IIF ANCA testing remains effective as a screening test, demonstrating standalone effectiveness.

Fatal outcome in isolated Pauci-immune pulmonary capillaritis: A case report.

Isolated Pauci-immune pulmonary capillaritis (IPIPC) is a rare form of small vessel vasculitis that affects only the lungs, causing inflammation of pulmonary capillaries and potentially leading to severe outcomes like alveolar haemorrhage. A 23-year-old woman with a prior diagnosis of rheumatoid arthritis presented with hemoptysis and respiratory distress, ultimately diagnosed with IPIPC. Despite treatment with high-dose steroids and intravenous immunoglobulin, her condition deteriorated, resulting in respiratory failure and death. IPIPC often lacks systemic symptoms and ANCA positivity, complicating diagnosis and treatment. Imaging, bronchoscopy, and histopathology are key for diagnosis, while management typically involves corticosteroids and possibly immunosuppressives. The case underscores the challenges in identifying and treating IPIPC, highlighting the importance of early intervention to improve prognosis, even though complications can still lead to significant respiratory issues and mortality.

ANCA and Anti-glomerular Basement Membrane (GBM) Dual Antibody Positivity: A Case Series and Proposal for a Clinical Classification

ANCA and Anti-glomerular Basement Membrane (GBM) Dual Antibody Positivity: A Case Series and Proposal for a Clinical Classification

Unmasking the nature of granulomatosis with polyangiitis – a diagnostic odyssey revealed through a compelling case report

Introduction and aim. Granulomatosis with polyangiitis (GPA), formerly known as Wegener’s granulomatosis, presents a formidable challenge in the realm of autoimmune diseases. Granulomatosis, characterized by vasculitis and granuloma formation, exhibits diverse clinical manifestations. The rarity of GPA is evident, with an estimated incidence between 0.4 and 11.9 cases per 1 million person-years. The aim of this report is to show the complex diagnostic challenges inherent in GPA, demonstrating the diagnostic process from initial symptoms. Description of the case. This case report unfolds the diagnostic journey of a 52-year-old Caucasian male. The presented case, initially suspected as a respiratory infection, led to a comprehensive investigation owing to persistent symptoms, abnormal blood counts, and elevated inflammatory markers. This narrative aims to depict the patient’s diagnostic journey. Key diagnostic tools include ANCA testing, imaging studies, and tissue biopsy. Pulmonary nodules, lymphangitic changes, and renal involvement culminating in a GPA diagnosis confirmed by positive ANCA and anti-PR3 antibodies. The successful management of this case involved a tailored therapeutic regimen, including cyclophosphamide and methylprednisolone, addressing both vasculitic and renal components. Conclusion. This case contributes to the understanding of atypical presentations of GPA, emphasizing the importance of a holistic and dynamic diagnostic approach.

Red flags for clinical suspicion of eosinophilic granulomatosis with polyangiitis (EGPA)

BackgroundEosinophilic granulomatosis with polyangiitis (EGPA), is a rare ANCA-associated systemic vasculitis. Its overlapping features with other vasculitic or eosinophilic diseases, and the wide and heterogeneous range of clinical manifestations, often result in a delay to diagnosis. ObjectiveTo identify red flags that raise a suspicion of EGPA to prompt diagnostic testing and to present an evidence-based clinical checklist tool for use in routine clinical practice. MethodsSystematic literature review and expert consensus to identify a list of red flags based on clinical judgement. GRADE applied to generate a strength of recommendation for each red flag and to develop a checklist tool. Results86 studies were included. 40 red flags were identified as relevant to raise a suspicion of EGPA and assessed by the experts as being clinically significant. Experts agreed that a diagnosis of EGPA should be considered in a patient aged ≥6 years with a blood eosinophil level >1000 cells/µL if untreated and >500 cells/µL if previously treated with any medication likely to have altered the blood eosinophil count. The presence of asthma and/or nasal polyposis should reinforce a suspicion of EGPA. Red flags of asthma, lung infiltrates, pericarditis, cardiomyopathy, polyneuropathy, biopsy with inflammatory eosinophilic infiltrates, palpable purpura, digital ischaemia and ANCA positivity, usually anti-myeloperoxidase, among others, were identified. ConclusionThe identification of a comprehensive set of red flags could be used to raise a suspicion of EGPA in patients with eosinophilia, providing clinicians with an evidence-based checklist tool that can be integrated into their practice.

#2291 ANCA negative vasculitis—the unmet need within small vessel vasculitis

Abstract Background and Aims ANCA negative small vessel vasculitis with renal involvement has been described in a number of cohorts. Though comprehensive studies comparing these individuals to ANCA positive patients are lacking and they are routinely excluded from clinical trials. Whilst the numbers are smaller than those with ANCA positivity, they still make up a large proportion of small vessel vasculitidies (Fig. 1). The absence of detectable circulating ANCA is thought to indicate a distinct spectrum of the disease. There remains unanswered questions regarding the pathophysiology, diagnosis and management of patients with seronegative AAGN. We present data from Croatian referral center. Method Study included 106 AAV patients with biopsy proven renal involvement in the period from 2007-2017. Category variables were analysed with Fisher Exact test and continuous with Kruskal-Wallis test. Statistical difference was then analysed post hoc with Chi-square test. Kaplan Meyer survival analysis and multivariate Cox proportional hazard regression analysis were used to explore difference between clinical phenotypes and finding significant predictors regarding outcomes which were defined as combined outcome end-stage renal disease and death (ESRDD), ESRD alone, the death outcome alone and relapse rate. Results 106 AAV patients with renal involvement were included: 66 (61.1%) MPA, 20 (18.5%) GPA, 20 (18.5%) RLV. 14 (13%) were PR3-ANCA positive, 57 (52.8%) MPO ANCA positive, 5 (4.6%) PR3-ANCA+MPO-ANCA and 32 (29.6%) ANCA negative patients. ANCA negative patients were comparatively younger (p = 0.02) and presented with more renal limited vasculitis (RLV; p < 0.001), lower BVAS (p = 0.003) and lower CRP (p = 0.001). ANCA negative patients usually presented with nephrotic syndrome compared to positive ones which presented with rapid progressive nephritic syndrome or acute nephritic syndrome (p = 0.027). 24-hour proteinuria levels were higher in ANCA negative group (p = 0.003). Though statistical difference was not reached, there was tendency for ANCA negatives to receive less plasmapheresis (p = 0.074). Histologically there were no differences between ANCA positive and ANCA-negative patients. On sub analysis ANCA negatives versus individual seropositive groups, there was tendency that ANCA negatives and MPO-ANCA patients had lower percentage of glomerular crescents (p = 0.092) but more acute tubular damage (p = 0.087). There were no differences in clinical outcomes between the groups. Conclusion ANCA negative vasculitis form a large proportion of small vessel vasculitidies and present with different clinical laboratory and histological (renal) characteristics than ANCA positive ones. More often than not disease seems to be renal limited and patients tend to be younger. Due to the rarity of the disease, there remains unanswered questions regarding the pathophysiology, diagnosis and management of these patients. This study highlights noteworthy distinctions between the two groups. Whether these differences warrant adjustments in treatment algorithms or a reconsideration of the classification of small vessel vasculitis remains to be determined. Further investigation into the pathogenetic mechanisms of seronegative AAVs is essential.

#1156 Outcomes after kidney transplantation in ANCA-associated vasculitis

Abstract Background and Aims ANCA-associated vasculitis with glomerulonephritis (AAV-GN) can lead to end-stage kidney disease (ESKD), requiring replacement therapy with dialysis or kidney transplant (KT). Few large studies evaluated the outcome of these patients after KT. Our aim was to describe, in comparison with a control group, the occurrence of the following events: delayed graft function recovery, graft survival, relapse, acute rejection, overall survival; and to study the risk factors associated with these events. Method This was a retrospective, multicenter (6 French centers), observational study including patients who received a KT between 2005 and 2023 for ESKD secondary to AAV-GN. Each vasculitis case receiving a KT was matched with 2 controls, matched on gender, center, recipient age (±5 years) and transplant period (±1 year). Event-free survival and the associated risk factors were analyzed. Results 369 patients were included, including 123 with AAV-GN and 246 control patients. The median post-KT follow-up for all patients was 58 months. There was no difference in the occurrence of DGF between the groups (18 vs 17%, p = 0.9). In univariable analysis, graft survival was lower in the AAV-GN group compared to the controls (76% vs 81% at 10 years, p = 0.017) (Fig 1A). 10 patients experienced a relapse after KT. ANCA positivity at the time of transplantation appeared to be correlated with relapse. There was no difference in the incidence of acute rejection between the groups (p = 0.44). In univariable analysis, overall survival tended to be lower in AAV-GN patients compared to controls (62% vs 73% at 10 years, p = 0.084) (Fig. 1B). Conclusion Kidney transplantation is an interesting option for patients with AAV-GN: the relapse rate is low, and the occurrence of acute rejection is comparable to a population of control patients. However, in AAV-GN, graft survival and overall survival appear to be poorer than in control patients. Comparison with a matched AAV-GN population remaining on dialysis would be of interest to go further.

#1283 Rituximab in addition to plasma exchange, cyclophosphamide and steroids for treatment of anti-GBM disease

Abstract Background and Aims Anti-GBM disease is a rare antibody-mediated vasculitis, usually treated with plasma exchange (PEX), cyclophosphamide (CYC) and steroids. There are limited data regarding the use of B-cell depleting therapies such as rituximab (RTX). We investigate the use of the addition of rituximab for the treatment of Anti-GBM disease. Method Ten-year (2012-2023) single-centre retrospective cohort study of patients with anti-GBM disease treated with or without rituximab, in addition to standard care, as first-line therapy. A Cox-proportional hazards regression model incorporating age, sex, ANCA status, dialysis need at presentation, lung haemorrhage, CYC (oral or IV) and RTX treatment was used to identify disease/treatment factors associated with outcome (death, end-stage kidney disease [ESKD], infection). Results Forty-five patients are included; baseline demographics, disease characteristics, treatments and outcomes are summarised in Table 1. In the Cox regression model, only increasing age was associated with risk of death (HR 1.08 [95% CI 1.02-1.17]). Age (HR 1.04 [1.01-1.08]), female sex (HR 4.93 [1.80-4.87]), and dialysis need at presentation (HR 5.28 [1.54-17.53]) were associated with ESKD-risk. Increasing age (HR 1.04 [1.00-1.09] and ANCA positivity (HR 3.08 [1.14-8.71]) were associated with risk of infection. The addition of rituximab was not significantly associated with risk of death (HR 0.82 (0.24-2.87), ESKD (HR 1.54 [0.64-3.96]) or infection 2.06 [0.67-5.71]. Conclusion Addition of rituximab to standard treatment for anti-GBM disease was not associated with improved renal outcome or survival benefit. However, rituximab use permitted lower cumulative doses of CYC and reduction in the number of PEX, without an increased risk of infection. Rituximab may have a role as a CYC- and PEX-sparing treatment in patients with anti-GBM disease.

#760 Monogenic lupus with ANCA associated vasculitis-phenotype and ANCA positivity due to DNASE1L3 mutations: case report and review of the literature

Abstract Background and Aims Monogenic systemic lupus erythematosus (SLE) accounts for 7-10% of cases of early-onset SLE. DNASE1L3 is an extracellular nuclease that digests chromatin released from apoptotic cells and its deficiency, enhance autoantibody production and type I interferon responses and cause different autosomal recessive phenotypes including SLE and hypocomplementemic urticarial vasculitis syndrome (HUVS) [1]. In some cases patients can have a mixed SLE-AAV phenotype. Kidney involvement in patients with DNASE1L3 mutations is poorly characterised. Method We present the case report of a 7-years-old boy with monogenic SLE due to DNASE1L3 mutations who developed severe glomerulonephritis leading to kidney failure. Results The patient had a history of urticaria and arthralgia and presented with fever, haemolytic anaemia, lymphadenopathy, hepato-splenomegaly, erythematous- macular and necrotic skin lesions, and interstitial lung disease. He also had acute kidney injury (serum creatinine 5.4 mg/dL), nephrotic- range proteinuria (3.9 g/24 h) and microhaematuria. Immunological tests revealed low C3 and C4, positive anti-nuclear antibody (ANA) and myeloperoxidase-antineutrophil cytoplasmic antibodies (MPO-ANCA), with negativity of anti-extractable nuclear antigen antibodies (anti-ENA) and anti-double stranded DNA (anti-dsDNA). Kidney biopsy showed pauci-immune (mesangial C3+ and IgG+) necrotising crescentic glomerulonephritis. The patient proved refractory to standard immunosuppression with cyclophosphamide and steroids. Two years later, due to renal function decline, a new kidney biopsy was performed and showed diffuse necrotising glomerulonephritis with endo- and extra-capillary proliferation; intense mesangial and subendothelial full-house deposits were evident on immunofluorescence. The patient did not respond to other lines of immunosuppression (mycophenolate mofetil, tacrolimus, azathioprine, rituximab), including the JAK inhibitor ruxolitinib. Kidney failure progressed to end stage at the age of 15 years, when the patient began haemodialysis. The kidney presentation, immunological profile and the first kidney biopsy led to diagnosis of AAV. However, the diagnosis was questioned due to the refractory course, the systemic clinical presentation and the second kidney histology (consistent with lupus nephritis). High interferon signature was detected and in the suspicion of a monogenic lupus nephritis Whole Exome Sequencing was performed and revealed homozygous DNASE1L3 variants (c.290_291delCA p.T97Ifs*2); thus, a final diagnosis of DNASE1L3 monogenic SLE was made. DNASE1L3 serum levels were normal but the DNAse enzymatic activity was low. Conclusion Renal involvement is one of the most frequent manifestations of DNASE1L3-related lupus; in the literature 32 cases of DNASE1L3-associated lupus nephritis are described. ANCA are positive in about 55% of these cases and are associated with a mixed lupus-AAV phenotype. All cases are characterized by resistance to common immunosuppressors and poor renal prognosis [2]. DNASE1L3 regulates neutrophil extracellular trap (NET) clearance and when this function is reduced the permanence of NETs induces endothelial damage and autoantibody formation. This pathogenic pathway is shared both by SLE and by AAV. There is no association between specific mutations and antibody positivity or clinical manifestations.

Hydralazine use can be associated with IgM-dominated immune complex-mediated glomerulonephritis

ABSTRACT Context IgM-dominant immune complex-mediated glomerulonephritis (IgM-dominant ICMGN) is a rare renal entity, characterized by a membranoproliferative pattern by light microscopy, dominant IgM staining by immunofluorescent staining, and subendothelial deposits by electron microscopy. This study was to investigate if some of IgM-ICMGN were associated with autoimmune disorders induced by hydralazine. Design Seven IgM-dominant ICMGN cases were identified over 8 years. Their pathologic phenotypes and clinical scenarios were analyzed in detail. Results Patients’ ages ranged from 47 to 87 years old with 5 women and two men. Six of seven patients had drug-induced autoimmune phenomenon (hydralazine-induced positive ANCA and ANA). All of them had renal dysfunction and some proteinuria. Most pathologic features showed a membranoproliferative pattern of glomerulonephritis with dominant IgM deposits at subendothelial spaces. IgM nephropathy (a variant of focal segmental glomerulosclerosis), chronic thrombotic microangiopathy, and cryoglobulinemic glomerulopathy were ruled out in the cases. Conclusion The hydralazine-induced autoimmune phenomenon can be seen in IgM-dominant ICMGN, which should be classified as a subtype of membranoproliferative glomerulonephritis.

P030 Multiple autoantibody formation post COVID-19 infection

Abstract Background/Aims COVID-19 has been linked to the formation of a number of autoantibodies. This case is an important reminder to clinicians interpreting autoantibody results in conjunction with clinical manifestations. A previously fit 51 year old gentleman, with no prior history of autoimmune disease required admission with respiratory symptoms in April 2020 consistent with COVID-19 infection. His acute respiratory illness was complicated by empyema and left-sided pneumothorax requiring left pleural decortication and adhesiolysis under (VATS). Persistent respiratory symptoms and fatigue lead to investigations for long COVID. Positive antibodies detected were dsDNA 166IU/ml, Proteinase 3 antibodies 20IU/ml, Myeloperoxidase antibodies 32IU/ml, IgG anticardiolipin antibodies 90IU/ml and Glomerular basement membrane antibodies 351 IU/ml. Negative autoantibodies included ANA, RF, aCCP, b2GPI, smooth muscle, AMA and myositis related antibodies. Methods There were no clinical signs or symptoms of inflammatory arthropathy, vasculitis, thrombosis or connective tissue disease. Other investigations included a CT thorax showing no new lung lesions, unremarkable urine dipstick, normal urine ACR, normal US abdomen, CT sinuses and MRI brain. Results Trial course of prednisolone was given therapeutically due to long COVID symptoms. There was no significant impact on symptoms/ autoantibody titres thus steroids were discontinued. The patient was followed closely by the rheumatology team for two years. During that time, the autoantibody levels gradually decreased, and he did not develop clinical signs of autoimmune disease. His long COVID symptoms persisted, and he remains under the long COVID clinical team. Conclusion COVID-19 infection is known to cause an immune response. There have been published cases of positive ANA, U1-snRNP anti-SS-B/La, ANCA, anti-phospholipid and anti-SRP antibody formation following COVID-19 infection. The link between the pathophysiology of COVID-19, autoantibody formation and the role of autoimmunity is still unclear. This man's case was unusual in the number and variety of autoantibodies formed post COVID, this has not been reported in the literature to date. Some of the autoantibodies detected are highly specific for certain conditions, for example anti-GBM antibodies have a high specificity for Goodpasture’s syndrome, thus this case also illustrates the need to interpret positive autoantibodies in the context of clinical findings and history. Disclosure S. Islam: None. N. Erb: None.

P023 A case of ANCA-associated vasculitis with possible IgG4-related disease

Abstract Background/Aims IgG4-related disease (IgG4-RD) and granulomatous polyangiitis (GPA) have apparent different pathology. There are infrequent reports of the two conditions occurring simultaneously. We add to the literature by describing a patient who appears to have both conditions. Methods A 65-year-old male presented with low back pain radiating to the perineum. His past history included T2DM, CABG and ablation for AF. Initial investigations showed a CRP of 102mg/ml and an eGFR of > 90ml/hr. A CT urogram revealed possible aortitis. A dedicated aortogram showed a cuff of added tissue around the infrarenal aorta and iliac arteries. A whole aortogram showed an increase in the abnormal tissue and detected a left upper lobe cavitating lesion. A PET-CT scan showed activity in the infrarenal aortic tissue, with focal uptake in the aortic arch and right superficial femoral artery. Several pleural based and parenchymal lesions showing moderate increased FDG activity were seen. A CT scan of the sinuses showed multifocal sinonasal mucosal thickening without bony erosions. C-ANCA was positive at 1/40, with raised PR3 of 32U/ml and IgG4 of 2.2g/L. Other immunoglobulin levels were normal and IGRA was negative. A biopsy of the lung lesion showed necrotising granulomatous inflammation and surrounding palisading histocytes, withno vasculitic element. Treatment with prednisolone 40mg daily and methotrexate 15mg weekly was started. A quick symptomatic improvement followed. CRP fell to 14mg/ml within two months. It was discussed in the national IgG4-RD MDT, and the consensus was that he had features of both GPA and IgG4-RD. A follow-up CT scan showed reduction in the volume of para-aortic tissue, with regression of some lesions in the chest, while others increased. However, he remains well with a normal CRP, stable renal function and normal urinalysis. His latest IgG4 level dropped to 0.67 g/L. Results The ANCA positivity and lung biopsy findings satisfy classification criteria of GPA. While aortic involvement is not commonly seen in GPA; it is typical of IgG4-RD; however, its diagnostic criteria require a confirmatory biopsy. This is challenging due to the risk of sampling around the aorta and ureters. Our case fulfils criteria for ‘possible’ IgG4-RD. In retrospect, an earlier PET CT scan may have spared the patient several CT scans. Conclusion The co-existence of IgG4-RD and ANCA-associated vasculitis may be more common than might be expected. Our case highlights the usefulness of early PET-CT scanning in rheumatic conditions. It is important to check ANCA in suspected IgG4-RD cases. It is possible that future AI programmes may help clinicians better judge the timing of investigations that may be more expensive, invasive or have increased radiation exposure in such complex cases. Finally, the usefulness of a national MDT for IgG4-RD is highlighted. Fortunately, treatment modalities are similar for both conditions. Disclosure H. Eltahir: None. M. Lloyd: None.

Interstitial lung diseases associated with ANCA positivity: A different disease spectrum from interstitial pneumonia with autoimmune features

BackgroundAnti-neutrophil cytoplasmic antibody (ANCA) is a type of autoantibodies associated with vasculitis. ANCA positivity is commonly observed in interstitial lung disease (ILD) patients. 7%-10% of ANCA-positive ILD patients don't present any symptoms of systemic vasculitis and are termed ANCA-positive idiopathic interstitial pneumonia (ANCA-IIP). Some researchers propose that ANCA-IIP should be categorized as interstitial pneumonia with autoimmune features (IPAF), although the official ATS/ERS statements exclude ANCA-IIP from this classification. Whether ANCA-IIP should be categorized into the entity of IPAF is still debatable. MethodsPatients diagnosed with ANCA-IIP and those with IPAF were analyzed in a retrospective study of ILD. The clinical outcomes were determined through pulmonary function tests (PFTs) after a one-year follow-up, as well as assessing all-cause mortality. Results27 patients with ANCA-IIP and 143 patients with IPAF were analyzed from a cohort of 995 patients with ILD. Patients in the ANCA-IIP group had an older age and a high proportion of males compared to those in the IPAF group. PFT results at baseline were similar between the two groups, except for a better FEV1% in the ANCA-IIP group. Glucocorticoid and immunosuppressive therapy improved pulmonary function in patients with IPAF, but it continued to deteriorate after one year of treatment in the ANCA-IIP group. Furthermore, the all-cause mortality rate was significantly higher in the ANCA-IIP group than in the IPAF group (22.2% vs. 6.3%, P = 0.017). ConclusionThe responses to glucocorticoid and immunosuppressive therapy differ between the ANCA-IIP and IPAF groups, leading to divergent prognoses. Therefore, it is inappropriate to classify ANCA-IIP as part of IPAF.

АНЦА-ассоциированные интерстициальные заболевания легких и интерстициальная пневмония с аутоиммунными признаками

Interstitial lung disease (ILD) is a recognized manifestation of ANCA-associated vasculitis. In addition, patients with idiopathic interstitial pneumonia and ANCA positivity but without other manifestations of systemic vasculitis (ANCA-ILD) have also been reported.

Cardiac involvement in eosinophilic granulomatosis with polyangiitis: acute eosinophilic myocarditis and chronic inflammatory cardiomyopathy

Abstract Objectives Currently, cardiac involvement is used to describe all eosinophilic granulomatosis with polyangiitis (EGPA) cardiac problems. However, heterogeneity exists among them. We aimed to depict the disease spectrum of EGPA cardiac involvement and identify the high-risk population. Methods We included EGPA patients hospitalized in our centre from 2012 to 2023 and in public databases. Based on the cardiac enzymes, cardiac MRI and endomyocardial biopsy results, the patients were divided into three groups: eosinophilic myocarditis (EGPA-EM), chronic inflammatory cardiomyopathy (EGPA-ICM) and EGPA-Control. Their clinical, laboratory, imaging results and prognoses were collected and compared. Results A total of 193 EGPA patients were included, 118 with cardiac involvement (74 EGPA-EM, 44 EGPA-ICM) and 75 control. Among EGPA-Control, EGPA-ICM and EGPA-EM, eosinophil increased (6.12/8.71/10.42 × 109/l, P < 0.01), ANCA positivity decreased (41.33/31.82/14.86%, P < 0.01) and lung involvement was reduced (73.33/72.73/43.24%, P = 0.02). In EGPA-EM, cardiac troponin was further elevated (0.27 vs 6.00 ng/ml, P < 0.01), ejection fractions decreased (57.79 vs 33.20%, P < 0.01) while more ST-T abnormality was observed (41.89 vs 20.45%, P = 0.02). The prognosis of EGPA-EM was significantly worse, with a 14.86% death rate and 2-year event-free survival rate below 50%. Furthermore, we proposed a LATE-EAST diagnostic score (7 items, 9 points) to discriminate EGPA-EM from EGPA-ICM using 4 points as threshold [area under the receiver operating characteristic curve 0.85 (95% CI 0.78–0.92), sensitivity 0.78, specificity 0.86]. Conclusions We first proposed different subtypes of cardiac involvement in EGPA. Identification and treatment of EGPA-EM needs improvement. LATE-EAST score could recognize the high-risk EGPA-EM effectively. Multi-disciplinary treatment is warranted, immunosuppressive therapy should be given in a timely manner and anti-IL-5 antibodies should be be tested in trials.

Lane–Hamilton Syndrome: A Vasculitis Mimic Presenting with Diffuse Alveolar Haemorrhage and Positive ANCA Testing

Lane–Hamilton Syndrome: A Vasculitis Mimic Presenting with Diffuse Alveolar Haemorrhage and Positive ANCA Testing

Association of atypical anti-neutrophil cytoplasmic antibody with comorbidities and outcome in a hospital-based population

IntroductionAtypical anti-neutrophil cytoplasmic antibody (a-ANCA) is characterized by a positive fluorescence staining other than typical cytoplasmic or perinuclear ANCA. ANCA is associated with increased risk of dialysis and mortality in patients with ANCA vasculitis. However, comorbidities related to a-ANCA and whether a-ANCA exhibits an increased risk for renal failure and mortality remain unclear. This study aimed to explore the comorbidities and outcome associated with a-ANCA. Materials and methodsThis retrospective study enrolled 164 and 170 patients with typical ANCA and a-ANCA positivity, respectively, who visited Taichung Veterans General Hospital, Taiwan from January 2016 to March 2021. Logistic regression analysis was used to determine risk factors and the rheumatological diagnosis associated with a-ANCA. Cox proportional hazard regression and Kaplan–Meier curves were employed to identify variables associated with 5-year renal survival and mortality. ResultsPatients with a-ANCA had lower chance of ANCA-associated vasculitis (OR: 0.02, 95 % CI: 0.01–0.07 p < 0.001), and systemic lupus erythematosus (OR: 0.23, 95 % CI: 0.11–0.48, p < 0.001), but a higher risk of rheumatoid arthritis (OR: 2.99, 95 % CI: 1.15–7.83, p = 0.025) and ulcerative colitis (OR: 5.50, 95 % CI: 1.20–25.29, p = 0.028). Patients with a-ANCA had a better renal survival (OR: 0.14, 95 % CI: 0.08–0.24, p < 0.001) and lower mortality (OR: 0.31, 95 % CI: 0.16–0.60, p = 0.001) than patents in the typical ANCA group. The 5-year renal survival and mortality was 89.3 % and 8.8 %, respectively, in patients with a-ANCA. ConclusionPatients with a-ANCA had better renal survival and lower mortality rates compared to patients with typical ANCA. These real-world data provide evidence of the long-term outcome and shed light on avenues for the strategic management of patients with a-ANCA.

IgG4-related Hypertrophic Pachymeningitis with Serum ANCA Positivity.

IgG4-related Hypertrophic Pachymeningitis with Serum ANCA Positivity.

Abstract 17436: A Diagnostic Copycat: Culture Negative Endocarditis of A Bioprosthetic Valve Presenting as ANCA Vasculitis

A 59-year-old female with a history of bicuspid aortic valve (AV) complicated by aortic stenosis and ascending aortic aneurysm s/p bioprosthetic AV and ascending aorta replacement presented with a 6-month history of weight loss, fatigue, and lower extremity rash. Initial laboratory workup identified anemia, leukopenia, and acute kidney injury with proteinuria and microscopic hematuria. Further workup included negative blood cultures, elevated inflammatory markers, elevated rheumatoid factor, hypocomplimentemia, and ANCA positivity (PR3 Ab positive). Biopsy of her palpable purpuric rash demonstrated vascular immune deposition pattern consistent with leukocytoclastic vasculitis. Renal biopsy revealed focal and crescentic glomerulonephritis with immune complex deposition. CT abdomen noted mesenteric lymphadenopathy with fluid surrounding the thoracic aortic graft. Surface echocardiogram showed bioprosthetic AV replacement with diffuse cusp thickening without stenosis or regurgitation. At this point, a multidisciplinary team offered a broad differential diagnosis of inflammatory vasculitis versus culture-negative endocarditis with plan for further testing. Follow-up whole-body and cardiac PET scan identified FDG-avid abnormalities involving the aortic graft and AV with hypermetabolic soft tissue thickening surrounding the aortic root. Transesophageal echocardiogram confirmed AV thickening with a 1 cm mobile echodensity. Additional serologic testing identified positive Bartonella henselae IgG (1:8192) and IgM (&gt;1:20) titers. The final diagnosis was B. henselae prosthetic AV endocarditis and ascending aortic graft infection. She underwent repeat AV and ascending aortic graft replacement, with graft material positive for B. henselae PCR and was treated with a course of doxycycline and rifampin. B. henselae is a fastidious gram-negative bacterium that can cause culture negative endocarditis but is very rarely associated with aortic graft infection. This case highlights (1) a rare example of B. henselae aortic graft infection, (2) the difficulty in differentiating B. henselae endocarditis from inflammatory vasculitis, and (3) the importance of engaging multidisciplinary teams to solve difficult diagnostic cases.