Hypersensitivity pneumonitis occurs in lungs as a result of type IV hypersensitivity reaction against various types of antigens sourced from animals, plants, fungi, bacteria, or low-molecular-weight chemical agents including isocyanates or metal fumes. Although more sophisticated tests may be required for definitive diagnosis, initial suspicion may develop only if the patient’s medical history is detailed in terms of environmental or occupational exposures. Herein, we report a 32-year old male patient presented with dyspnea, dry cough, fatigue, and weight loss. Previous treatments for respiratory infections and asthma suggested by another center had failed. He was consulted to our occupational disease’s unit for any possible occupational lung disease including pneumoconiosis, due to his employment in production of stainless-steel kitchen equipment. Detailed anamnesis revealed that the patient was also a pigeon breeder. Combining both detailed anamnesis of relevant exposures and supporting findings in high-resolution computed tomography of the chest and bronchoalveolar lavage cytology, the patient was diagnosed as hypersensitivity pneumonitis in collaboration with our hospital’s multidisciplinary team for pulmonary diseases.
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