Immunological Testing in Small-vessel Vasculitis
Conditions
Keywords
ANCA vasculitis, ANCA testing, antigen specific essays, IIF
Brief summary
Anti-neutrophil cytoplasm antibodies (ANCA) are defined as important serological markers for the diagnosis of some forms of small vessel vasculitis, including granulomatosis with polyangiitis (GPA) , microscopic polyangiitis(MPA) and to a lesser extent Churg -Strauss syndrome or Eosinophilic granulomatosis with polyangiitis (EGPA).So they are called ANCA-associated vasculitis(AAV). An international consensus statement for ANCA testing statement was issued in 2017 and states that the antigen specific immunoassays can be used for the accurate diagnosis of ANCA-associated vasculitis without the need for indirect immunofluorescence(IIF). In the present study we will test whether the antigen specific assays screening is a valuable alternative to IIF confirming with immunoassay for the diagnosis of AAV on a number of patients and controls. Aim To evaluate the performance of the recommended strategy for the detection of ANCA based on screening with antigen specific immunoassays on a number of AAV patients and relevant disease controls In Kagawa university hospital (rheumatology department). Patients and methods This is a prospective study will be conducted at the department of rheumatology in Kagawa university hospital in which consecutive samples will be included from patients suspected to have AAV; patients subsequently identified as having AAV will be included as AAV patients, while patients in which the diagnosis AAV is rejected, will be included as disease controls. PR3-and MPO-ANCA will be performed using assays from Medical & Biological Laboratories Co (Anchor CLEIA) isayama.takuya@mbl.co.jp
Detailed description
To evaluate the performance of the recommended strategy for the detection of ANCA based on screening with antigen specific immunoassays on a number of AAV patients and relevant disease controls (i. e., patients for whom ANCA would be requested in the context of small-vessel vasculitis such as patients with infections, drug-induced diseases, connective tissue disease, etc.).
Interventions
DIAGNOSTIC_TESTIndirect immunofluorescence (IIF) , myeloperoxidase antibody(MPO)- and anti-proteinase 3 (PR3-) ANCA immunoassays
Measurement and evaluation of the ANCA testing
Sponsors
Sohag University
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
.All patients included must be older than 18 years and able to give informed consent. * Classification criteria and nomenclature for AAV are from the American College of Rheumatology * Serum sampling should be done before initiation of immunosuppressive treatment or no later than 2 weeks after onset of low-medium dose of immunosuppressive treatment (but this should be documented)
Exclusion criteria
.Patients younger than 18 years old
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Anti-proteinase 3 antibody (PR3), anti-myeloperoxidase (MPO) antibody presence in patients with small-vessel vasculitis versus patients without vasculitis | within two weeks of immunosuppressive treatment not after that | Antibodies are detected using chemiluminescent enzyme immunoassay (CLEIA).Values above 3.5 u/ml are considered positive |
Countries
Japan
Contacts
Primary ContactMai MF Mansour
Outcome results
None listed