Evaluation of Anti-neutrophil Cytoplasm Antibodies Test
Evaluation of Anti-neutrophil Cytoplasm Antibodies Test
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
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.).
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