title: Pneumomediastinum as a primary manifestation of chronic hypersensitivity pneumonitis.
abstract: BACKGROUND
  Patients with chronic hypersensitivity pneumonitis (HP) can present with an insidious onset of their disease without typical fluctuating flu-like symptoms, and there are only signs of chronic respiratory failure caused by the progressive fibrotic lung disease.
  
  
  METHODS
  A 45-year-old man with a pneumomediastinum and interstitial lung disease was referred for further investigations and therapy. No traumatic event or interventional procedure had occurred prior to referral. The patient had been working in farming for almost 20 years and was exposed in childhood by his father to pigeon breeding from childhood until 20 years ago. He reported dyspnea on exercise for the previous 2 years. High-resolution CT of the lung showed a pneumomediastinum and a fibrotic interstitial lung disease without dominating ground-glass opacities. Specific IgG antibodies were markedly elevated against molds and avian antigens. Bronchoalveolar lavage demonstrated a slightly lymphocytic and neutrophilic alveolitis. After recovering from the pneumomediastinum, an open lung biopsy was performed and a UIP-pattern was detected. An inhalative challenge with hay from the work-place was positive. A diagnosis of chronic farmer's lung was made.
  
  
  CONCLUSIONS
  Pneumomediastinum has been described in other fibrotic lung diseases, but until now it has not been described as a primary manifestation of chronic fibrotic HP. Particularly in cases of concurrent antigen sources, an inhalative challenge could be done, even in a chronic course of HP.
authors: Department of Pulmonary Diseases, Fachkrankenhaus Coswig, Centre for Pulmonary Diseases and Thoracic Surgery, Coswig, Germany. dr.koschel@fachkrankenhaus-coswig.de
authors: Dirk
authors: D
authors: Koschel
authors: Sabin
authors: S
authors: Handzhiev
authors: Carlos
authors: C
authors: Cardoso
authors: Axel
authors: A
authors: Rolle
authors: Olaf
authors: O
authors: Holotiuk
authors: Gert
authors: G
authors: Höffken
mesh_terms: D000542:Alveolitis, Extrinsic Allergic / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D001706:Biopsy; D002908:Chronic Disease; D006801:Humans; D008168:Lung / Q000473:pathology / Q000601:surgery; D008297:Male; D008478:Mediastinal Emphysema / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D012129:Respiratory Function Tests; D014057:Tomography, X-Ray Computed