Unabated occupational risk in a patient with rheumatoid pulmonary fibrosis

This case highlights the importance of considering hypersensitivity pneumonitis (HP) in the differential diagnosis of interstitial lung disease (ILD) and of obtaining an occupational history so that remediable risk factors may be identified and managed.

To report a case of a chicken sexer with severe rheumatoid arthritis (RA) who developed progressively worsening dyspnoea and restrictive lung disease associated with pulmonary fibrosis.

Clinical investigation included physical examination, occupational history, pulmonary function tests (PFTs), chest imaging and bronchoalveolar lavage (BAL), as well as serological tests including standard IgE bird feather mixture and local IgG precipitin preparation to chicken excrement. Lung histopathology was examined post-mortem.

The patient had worked as a chicken sexer for 29 years with limited control of exposure to chicken bioaerosols. PFTs initially showed mild restriction with a moderate gas transfer defect and computerized tomography of the chest exhibited extensive interstitial infiltrates throughout with severe honeycombing at the bases. Cytology from a BAL revealed multinucleated giant cells (MNGs). Specific serologic tests for bird antigens were negative. Histopathology demonstrated diffuse interstitial fibrosis with honeycombing, poorly formed granulomas and MNGs.

Findings were consistent with a diagnosis of HP with RA-associated ILD. The patient's history of severe RA biased the diagnosis to one of RA-associated ILD and her occupational risk had been less emphatically addressed. Obtaining a thorough occupational history can uncover exposures to workplace respiratory hazards and may create opportunities for intervention to limit morbidity from chronic lung disease.