Objective To highlight the characteristics of giant cell interstitial pneumonia ( GIP) . Methods The clinical, radiological, and pathological data of two patients with GIP pathologically proven by open lung and TBLB biopsy were presented respectively, and relevant literatures were reviewed. Results Patients with GIP usually had a history of exposure to metal dust. Clinical presentations included cough and dyspnea on exertion, and pulmonary function testing showed a restrictive abnormality. On chest radiography and high-resolution CT scans, it presented as bilateral areas of ground-glass attenuation, areas of consolidation, diffuse small nodules, extensive reticular opacities, and traction bronchiectasis. The main pathological findings included a desquamative interstitial pneumonia ( DIP) -like reaction with intra alveolar macrophages and numerous large multinucleated histiocytes that ingested inflammatory cells were admixed with macrophages. The finding of GIP was almost pathognomonic for hard metal pneumoconiosis. Conclusions GIP is a very rare chronic interstitial pneumonia, and has no characteristic clinical manifestations. Radiographic findings are similar to other idiopathic interstitial pneumonias. Careful collection of the occupational history can help to minimize misdiagnosis.
