Incidence of myeloperoxidase anti-neutrophil cytoplasmic antibody positivity and microscopic polyangitis in the course of idiopathic pulmonary fibrosis.

Abstract

BACKGROUND:

Pulmonary fibrosis is a manifestation of microscopic polyangitis (MPA), and often precedes the detection of MPA. The prevalence and sequence of myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) and MPA in patients initially diagnosed with idiopathic pulmonary fibrosis (IPF) have not been precisely elucidated.

METHODS:

We enrolled 61 consecutive patients with IPF and measured the MPO-ANCA titers at initial presentation and during the follow-up period. Clinical, radiologic and histologic features of MPO-ANCA-positive cases were examined.

RESULTS:

Of 61 patients, 3 (4.9%) had positive MPO-ANCA titers at the initial presentation of IPF. During the disease course, MPO-ANCA-positive conversion occurred in 6 patients and the prevalence of ANCA increased to 14.8%. Among the nine patients positive for MPO-ANCA, two patients developed MPA during follow-up. Histologic features of MPO-ANCA-positive pulmonary fibrosis were compatible with the usual interstitial pneumonia pattern in which alveolar hemorrhage and capillaritis were not observed. The patients with MPO-ANCA-positive conversion showed increased percentages of bronchoalveolar lavage eosinophils and more frequent complication of pulmonary emphysema compared to those with MPO-ANCA-negative IPF.

CONCLUSIONS:

The findings of the present study demonstrated that patients with an initial diagnosis of IPF occasionally acquire MPO-ANCA, which develops to MPA during the disease course of IPF. The presence of pulmonary eosinophilia and low attenuation areas on computed tomography scans might be predictive of MPO-ANCA positive conversion.

• Authors: Masaru Ando, Eishi Miyazaki, Toshihiro Ishii, Yutaka Mukai, Mari Yamasue, Hideaki Fujisaki, Takeo Ito, Shin-ichi Nureki, Toshihide Kumamoto
• Journal: Respiratory medicine (Respir Med) Vol. 107 Issue 4 Pg. 608-15 (Apr 2013) ISSN: 1532-3064 [Electronic] England
• PMID: 23434037 (Publication Type: Journal Article)
• Copyright: Copyright © 2013 Elsevier Ltd. All rights reserved.

Chemical References

• Antibodies, Antineutrophil Cytoplasmic
• Glucocorticoids
• Immunosuppressive Agents
• Peroxidase

Topics

• Adult
• Aged
• Aged, 80 and over
• Antibodies, Antineutrophil Cytoplasmic (blood)
• Bronchoalveolar Lavage Fluid (cytology)
• Female
• Follow-Up Studies
• Glucocorticoids (therapeutic use)
• Humans
• Idiopathic Pulmonary Fibrosis (complications, diagnostic imaging, drug therapy, immunology)
• Immunosuppressive Agents (therapeutic use)
• Male
• Microscopic Polyangiitis (diagnostic imaging, drug therapy, etiology, immunology)
• Middle Aged
• Peroxidase (immunology)
• Tomography, X-Ray Computed
• Treatment Outcome