Vasculitis research: Current trends and future perspectives.

We discuss recent and prospective research in small and large vessel vasculitis. Large cohorts of Takayasu arteritis (TA) have been recently published from across the world, clarifying our understanding of this uncommon disease. Novel open-ended approaches like large-scale genotyping, proteomics and metabolomics have helped gain novel insights into TA, giant cell arteritis (GCA) and anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). Recent advances in the imaging of TA and GCA offer promise for earlier diagnosis and better monitoring of response to therapy. Although two randomized controlled trials of abatacept and tocilizumab failed to meet their primary end-points, successful large-scale studies of abatacept and tocilizumab in GCA hold promise for better disease control. While cyclophosphamide has revolutionized the management of AAV, increasing use of rituximab as an alternative induction regimen, as well as use of novel approaches involving reduced or no corticosteroid use for AAV and alternative agents such as avacopan (a complement 5a receptor antagonist) hold promise for lesser toxic induction regimens in the future. Increasingly, the risk of cardiovascular events and comorbidities such as osteoporosis are being recognized as factors affecting long-term prospects of patients with vasculitis. There is a shift in emphasis to utilize patient-reported outcomes to more accurately gauge the impact of vasculitides and their treatment.

Is granulomatosis with polyangiitis in Asia different from the West?

The incidence and clinical features of antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) have been shown to vary according to geographical areas, with granulomatosis with polyangiitis (GPA) being more common in northern Europe and microscopic polyangiitis (MPA) being more common in Asian countries. The annual incidence of GPA among Asians varies between 0.37/million to 2.1/million population. The prevalence of GPA has been estimated to be 1.94/100 000 in a Chinese population. Polymorphisms in class II major histocompatibility genes and ETS1 proto-oncogene has been shown in Asian patients with GPA. There is a difference in mean age at onset and proteinase 3 (PR3) or myeloperoxidase (MPO) positivity in GPA patients from different Asian countries. Those from India had mean age of 40 years and those from Japan had mean age of 65 years. Sixty percent of GPA patients from China and Japan were MPO ANCA positive while the majority of patients from India and Korea were PR3 positive. Geographical variation with lower frequency of renal involvement in Indian studies and higher frequency in Chinese patients has also been noted. Treatment outcomes have been similar to those reported from other parts of the world. Remission was achieved in about two-thirds of patients while relapses were noted in one-third to half of the patients. Apart from minor differences in the organ systems involved, MPO-ANCA GPA and PR3-ANCA GPA had similar rates of remission and relapses.

Clinical features and long-term outcomes of 105 granulomatosis with polyangiitis patients: A single center experience from north India.

AIM: To describe the clinical features, treatment and long-term outcomes in north Indian patients with granulomatosis with polyangiitis (GPA). METHODS: Clinical details, Birmingham Vasculitis Activity Score (BVAS-v3), laboratory data, histopathology findings, treatment details and outcomes of all consecutive patients diagnosed as having GPA between April 2005 and April 2016 were retrieved. European Vasculitis Study Group definitions were used to classify patients into localized, early systemic, generalized, severe and refractory categories. The findings were compared with large single center cohorts from USA, Germany and France. RESULTS: One hundred and five patients (median age 40 years; 60 females and 45 males) were diagnosed as having GPA. Median duration of follow up was 28 months. Upper respiratory tract, renal and lung involvement were seen in 76.19%, 51.43% and 67.62% of patients, respectively. Ocular, ear, central nervous system, peripheral nervous system, heart, gastrointestinal and skin involvement were seen in 40.95%, 18.1%, 26.67%, 11.43%, 5.71%, 12.38% and 29.52%, respectively. The median BVAS v3 score was 17. Localized, early systemic, generalized, severe and refractory disease were seen in three, 44, 38, 17 and one patient, respectively. Eighteen patients expired and the cause of death was disease activity in 11, disease activity plus sepsis in four and sepsis alone in three patients. Twenty-six patients experienced relapses. No hemorrhagic cystitis or bladder cancers were observed; however, one patient developed myelodysplastic syndrome during follow up. CONCLUSION: Indian patients are younger and have less arthritis, renal and peripheral nerve involvement as compared to the patients in Western cohorts.

Pauci-immune glomerulonephritis: does negativity of anti-neutrophilic cytoplasmic antibodies matters?

AIM: A significant proportion of pauci-immune glomerulonephritis (PIGN) patients are reported to have absence of anti-neutrophilic cytoplasmic antibodies (ANCA). However, studies are controversial regarding their significance and there is limited data after the new prognostic classification of PIGN. METHODS: Renal biopsy-proven cases of PIGN were included and their clinical details, ANCA status by immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA), Birmingham Vasculitis Activity Score (BVAS) and treatment outcomes at 6 months were noted. The renal biopsies were classified according to the proposed histopathological classification. Scoring was done from 0-3 for interstitial edema, interstitial fibrosis and tubular atrophy (IFTA), interstitial inflammation and arteriosclerosis. The percentage of glomeruli with sclerosis, cellular and fibrous crescents, and percentage of subjects with glomerulitis, tuft necrosis, interstitial granuloma and vasculitis were noted. RESULTS: Out of the 84 subjects included in the study, 33 (39.3%) were negative for ANCA by both IIF and ELISA. These subjects had significantly higher renal involvement, less extra-renal manifestations and lower BVAS. On histology, they had significantly higher proportion of crescentic class (66.7% vs. 41.2%, P = 0.039), higher number of cellular crescents (66.12% vs. 53.3%, P = 0.00008), higher IFTA (1.53 vs. 1.02, P = 0.009) and less interstitial edema (1.44 vs. 1.96, P = 0.003). The treatment outcomes were worse in ANCA-negative PIGN subjects, with significantly less improvement (37.2% vs. 62.8%, P = 0.02), more deterioration (40.7% vs. 14%, P = 0.006), and reduced probability of becoming dialysis free (31.6% vs. 69.6% P = 0.009). CONCLUSIONS: A negative ANCA in PIGN is associated with crescentic class, more IFTA and poor treatment outcomes.

Histopathological classification of pauci-immune glomerulonephritis and its impact on outcome.

Rapidly progressive renal failure is a common but severe feature of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. A histopathological classification for ANCA-associated pauci-immune glomerulonephritis was developed for prognostication of these patients. The present study aims to classify patients of pauci-immune glomerulonephritis according to this classification and its impact on outcome. Eighty-six subjects with pauci-immune glomerulonephritis between July 2006 and October 2012 were included in the study. Their renal biopsies were reviewed and classified into focal, crescentic, sclerotic and mixed class as per the new classification. The outcomes were analyzed after 6 months of treatment. Of the 86 subjects, 34 (39.53 %) were granulomatosis with polyangiitis, 36 (41.86 %) microscopic polyangiitis, 1 eosinophilic granulomatosis with polyangiitis, while the rest (17.44 %) were unclassifiable. Thirteen (15.5 %), 43 (51.2 %), 12 (14.3 %) and 16 (19 %) patients were classified as focal, crescentic, sclerotic and mixed class, respectively. The mean serum creatinine at baseline was 280.23, 659.46, 573.72 and 542.78 µmol/L in focal, crescentic, sclerotic and mixed class, respectively. The probability of improvement in renal functions at 6 months decreased from focal to crescentic to mixed to sclerotic class, while the probability of death was highest in the sclerotic class followed by the mixed class. This difference in outcome was maintained irrespective of the clinical diagnosis or the Birmingham Vasculitis Activity Score. Our study has shown that the histopathological classification can be used to predict the severity of renal dysfunction as well as the treatment outcomes in pauci-immune glomerulonephritis.