[Complex differential diagnosis of diffuse fine nodular lung infiltrates]

We report the case of a 36-year-old, previously healthy male patient presenting with progressive shortness of breath and dry cough. Chest X-ray revealed a diffuse micronodular interstitial pattern and pulmonary function tests showed reduced diffusion capacity, a restrictive pattern and obstructive airflow limitation. Transbronchial biopsy disclosed lymphangiosis carcinomatosa. The primary tumor was adenocarcinoma of the stomach. Differential diagnosis and the diagnostic approach to interstitial lung diseases are discussed. History, clinical findings, radiological and functional tests, as well as blood chemistry, serve to narrow down the differential diagnosis. The main further investigative steps are bronchoscopy with broncho-alveolar lavage and transbronchial biopsies, high resolution computer tomography, and thoracoscopic biopsy.