Arthritis & Rheumatism, Volume 60,
October 2009 Abstract Supplement
The 2009 ACR/ARHP Annual Scientific Meeting
Philadelphia October 16-21, 2009.
A Novel 60 Kda Reactivity in Cyclic Neutropenia: High Titer Classic ANCA Pattern and Negative Anti-Peroxidase-3
Rodrigues1, Camila E., Bonfa1, Eloisa, Velloso2, Elvira R.P., Teixeira1, Flávia K., Viana1, Vilma S.T, Bueno1, Cleonice, Kondo2, Andréa
To evaluate the presence of antineutrophil cytoplasmic antibodies (ANCA) in patients with chronic neutropenia.
Twenty-two patients with hematological disorders under granulocyte-colony stimulating factor treatment for neutropenia (10 with aplastic anemia, 2 cyclic neutropenia, 1 myelodysplastic syndrome, 1 auto immune pancytopenia and 8 chronic myeloid leukemia with imatinib mesylate neutropenia induced) were enrolled in the study. Patient's charts were extensively reviewed for demographic, clinical, laboratorial and therapeutic data. ANCA were detected by indirect immunofluorescence (IIF) using isolated human neutrophils and ELISA (myeloperoxidase and proteinase-3). Characterization of the antigenic specificity of these antibodies was performed by Western blot using crude extract of human neutrophils as source of antigen. Exclusion criteria were drug use that induces neutropenia (except for imatinib) or ANCA.
Among the 22 patients, an evident predominance of female gender (63.6%) and white race (86.3%) was observed. The mean age was 49 (from 17 to 79) years and mean disease duration was 38 months. Of note, ANCA were detected in two (9.1%) patients and both had cyclic neutropenia. These two sera displayed the classic ANCA pattern with high titer reactivity (1/1.260 and >= 2.520, respectively). The longitudinal evaluation of several frozen sera samples showed a persistent high titer classic ANCA pattern. Sera were uniformly negative for anti-peroxidade-3 and anti-mieloperoxidase antibodies. Western blot analysis revealed that serum from these two patients showed a common reactivity to a protein fraction with molecular weight of 60 kDa. One of these two patients during follow-up of 4 years had an additional diagnosis of large granular lymphocytic proliferation and none developed signs and symptoms compatible with Wegener granulomatosis.
A novel 60 kDa reactivity autoantibody is described in cyclic neutropenia which is characterized by high titer classic ANCA pattern with a uniformly negative anti-peroxidase-3 reactivity. The underlying inducing stimulus of this abnormal humoral response is not associated with granulocyte-colony stimulating factor treatment.
To cite this abstract, please use the following information:
Rodrigues, Camila E., Bonfa, Eloisa, Velloso, Elvira R.P., Teixeira, Flávia K., Viana, Vilma S.T, Bueno, Cleonice, et al; A Novel 60 Kda Reactivity in Cyclic Neutropenia: High Titer Classic ANCA Pattern and Negative Anti-Peroxidase-3 [abstract]. Arthritis Rheum 2009;60 Suppl 10 :1843