Antineutrophil cytoplasmic autoantibodies and clinical phenotype in patients with Churg-Strauss syndrome

Overall Disability Sum Score for Clinical Assessment of Neurological Involvement in Eosinophilic Granulomatosis With Polyangiitis

AIM

The aim of this study was to verify the application of Overall Disability Sum Score (ODSS) for standardized clinical assessment of neurological involvement in patients with eosinophilic granulomatosis with polyangiitis (EGPA) and its correlation with treatment response and long-term outcomes.

METHODS

Consecutive EGPA patients referred to our tertiary vasculitis center were retrospectively evaluated. Patients' neurological damage and disability were systematically assessed with Vasculitis Damage Index and ODSS.

RESULTS

Fifty EGPA patients were included in the study with a median follow-up of 75 months (9-180 months). Twenty-five (50%) developed peripheral neuropathy, 17 (68%) presented mononeuritis multiplex, whereas 8 (32%) had symmetric polyneuropathy. Patients with neurological involvement were older (56.3 ± 13.4 vs. 44.4 ± 12.1 years, P < 0.0009), more frequently antineutrophil cytoplasmic antibody positive (48% vs. 16%, P = 0.015), and were more likely to have renal involvement (24% vs. 0%, P = 0.022). An early clinical response to therapy was observed within 6 months of treatment, resulting in a significant decrease in ODSS, which fell from the baseline value of 4.2 ± 2.4 to 2.9 ± 1.5 (P = 0.0001), whereas only a slow decreasing pattern was noted over the long-term period. However, all subjects developed neurological impairment and disability despite remission from active vasculitis. Patients with ODSS of greater than 3 at baseline (n = 13 [52%]) retained a higher score at the last examination (P < 0.001), predicting a low therapeutic response. Furthermore, ODSS of greater than 3 was found associated with more neurological relapses (53.8% vs. 0%, P = 0.027).

CONCLUSION

Overall Disability Sum Score could be a rapid, simple, reliable instrument to evaluate the severity of disability and nerve damage due to neurological involvement caused by vasculitis and to predict, at presentation, improvement and risk of neurological worsening.

Eosinophils in vasculitis: characteristics and roles in pathogenesis

Eosinophils are multifunctional granular leukocytes that are implicated in the pathogenesis of a wide variety of disorders, including asthma, helminth infection, and rare hypereosinophilic syndromes. Although peripheral and tissue eosinophilia can be a feature of many types of small-vessel and medium-vessel vasculitis, the role of eosinophils has been best studied in eosinophilic granulomatosis with polyangiitis (EGPA), where eosinophils are a characteristic finding in all three clinical stages of the disorder. Whereas numerous studies have demonstrated an association between the presence of eosinophils and markers of eosinophil activation in the blood and tissues of patients with EGPA, the precise role of eosinophils in disease pathogenesis has been difficult to ascertain owing to the complexity of the disease process. In this regard, results of clinical trials using novel agents that specifically target eosinophils are providing the first direct evidence of a central role of eosinophils in EGPA. This Review focuses on the aspects of eosinophil biology most relevant to the pathogenesis of vasculitis and provides an update of current knowledge regarding the role of eosinophils in EGPA and other vasculitides.

Intravascular immunity as a key to systemic vasculitis: a work in progress, gaining momentum

Vascular inflammation contributes to the defence against invading microbes and to the repair of injured tissues. In most cases it resolves before becoming apparent. Vasculitis comprises heterogeneous clinical entities that are characterized by the persistence of vascular inflammation after it has served its homeostatic function. Most underlying mechanisms have so far remained elusive. Intravascular immunity refers to the surveillance of the vasculature by leucocytes that sense microbial or sterile threats to vessel integrity and initiate protective responses that entail most events that determine the clinical manifestations of vasculitis, such as end-organ ischaemia, neutrophil extracellular traps generation and thrombosis, leucocyte extravasation and degranulation. Understanding how the resolution of vascular inflammation goes awry in patients with systemic vasculitis will facilitate the identification of novel pharmacological targets and bring us a step closer in each patient to the selection of more effective and less toxic treatments.