RESUMEN
Perinuclear Anti Neutrophil Cytoplasmic Antibody (p-ANCA) is a serological marker of Microscopic Polyangiitis (MPA), a vasculitis associated with lung involvement potentially mimicking Idiopathic Pulmonary Fibrosis (IPF). In this study, we evaluated the role of p-ANCA in predicting clinical evolution and prognosis in a cohort of IPF patients. In this observational, retrospective, case-control study, we compared 18 patients with an IPF diagnosis and p-ANCA positivity with 36 patients with seronegative IPF, matched for age and sex. IPF patients with and without p-ANCA showed similar lung function decline during the follow-up, but IPF p-ANCA+ showed better survival. Half of IPF p-ANCA+ patients were classified as MPA for the development of renal involvement (55%) or skin signs (45%). The progression towards MPA was associated with high levels of Rheumatoid Factor (RF) at baseline. In conclusion, p-ANCA, mainly when associated with RF, could predict the evolution of Usual Interstitial Pneumonia (UIP) towards a definite vasculitis in patients, with a better prognosis compared with IPF. In this view, ANCA testing should be included in the diagnostic workup of UIP patients.
RESUMEN
A 74-year-old non-smoker female presented to our attention with a history of dyspnea and cough. CT scan revealed multiple areas of patchy ground glass attenuation associated to a diffuse mosaic oligoemia. Scattered bilateral subcentimetric pulmonary nodules were also present. Patient underwent a surgical lung biopsy. Specimens showed features of diffuse neuroendocrine hyperplasia, microhoneycombing, fibroblast foci. A final diagnosis of diffuse neuroendocrine hyperplasia with obliterative bronchiolitis and UIP was rendered.
