Chronic interstitial pneumonia and crescentic glomerulonephritis associated with perinuclear antineutrophil cytoplasmic antibodies

We examined a 72-year-old man suffering from chronic interstitial pneumonia with crescentic glomerulonephritis associated with perinuclear antineutrophil cytoplasmic antibodies (P-ANCA). Ten years before admission, he was given a diagnosis of interstitial pneumonia, but received no medication. He was admitted to our hospital because of a high fever and back pain. Antibiotics were used, but without success. The serum P-ANCA titer was high, and examination of a kidney biopsy specimen showed crescentic glomerulonephritis. Computed tomography of the chest showed that the lungs had a honecomblike appearance, and examination of a specimen obtained by transbronchial lung biopsy showed interstitial fibrosis. This case shows that interstitial pneumonia can be associated with P-ANCA. It is important to be a wore that crescentic glomerulonephritis associated with P-ANCA can develop in patients with interstitial pneumonia.