Can CT distinguish hypersensitivity pneumonitis from idiopathic pulmonary fibrosis?

Abstract

OBJECTIVE. The clinical management of patients with idiopathic pulmonary fibrosis differs markedly from that of patients with hypersensitivity pneumonitis. However, the two diseases often cannot be differentiated on clinical grounds. The purpose of this study was to establish whether CT can be used to make the distinction.MATERIALS AND METHODS. Thirty-six patients with idiopathic pulmonary fibrosis and 27 patients with hypersensitivity pneumonitis were studied. All diagnoses were confirmed or supported by open lung biopsy. Three of the patients with idiopathic pulmonary fibrosis had desquamative interstitial pneumonia, and the remainder had usual interstitial pneumonia. In 19 of the 27 patients with hypersensitivity pneumonitis, the disease was chronic (symptoms lasting more than I year), while eight had acute or subacute symptoms. Two radiologists, who had not previously seen any of the cases and were blinded to the diagnosis, reviewed the CT images by consensus.

Padrões tomográficos das doenças intersticiais pulmonares difusas com correlação clínica e patológica

“…(17,18) In patients with fibrosing lung disease and having been exposed to HP-provoking antigens, a clinical diagnosis can be accepted, provided that the CT context is appropriate and the BAL cytology reveals lymphocytosis. (19) Fibrosing sarcoidosis (stage IV)…”

Multidisciplinary interobserver agreement in the diagnosis of idiopathic pulmonary fibrosis

“…Since the diagnosis of IPF depends upon the expertise of the pathologist and radiologist, it is important that the clinician knows the diagnostic accuracy of thoracic HRCT and of lung biopsy in UIP. Various studies have calculated the accuracy of thoracic HRCT in fibrotic lung diseases [5][6][7], evaluated interobserver agreement for the diagnosis of different thoracic HRCT patterns (e.g. ground-glass and reticular pattern) [8,9] in patients with biopsy-proven nonspecific interstitial pneumonia (NSIP) or UIP [3], or in different forms of interstitial lung disease [10,11].…”

Chronic Hypersensitivity Pneumonitis Caused by Aspergillus Complicated with Pulmonary Aspergilloma

“…Lynch et al reported that patients with IPF were more likely to have honeycombing and peripheral or lower lung zone predominance of the disease, and less likely to have micronodules, than were patients with CHP (9). They concluded that CT can be used to distinguish IPF from CHP in most but not all cases and lung biopsy should still be considered the golden standard (9). The present patient had fibrosis situated predominantly in the lower lobe, but fibrosis was also found in the upper and middle lung zones.…”