Benign Pulmonary Disease

 A. Classifications: 
  1. Acute vs. chronic 
  2. Acinar vs. interstitial 

 B. Acute, Diffuse, Benign Pulmonary Disease 
  1.  Acute infectious pneumonias 
  2.  ARDS 
  3.  Acute cardiogenic pulmonary edema 
  4.  Vasculitic-immunologic syndrome 

 C. Chronic Diffuse Benign Pulmonary Disease 
  1.  Sarcoidosis 
  2.  Hypersensitivity pneumonitis (organic ducts) 
  3.  Pneumoconiosis 
  4.  Connective tissue diseases 
  5.  Lung Irradiation 
  6.  Drug-induced toxicity 
  7.  Eosinophilic granuloma 
  8.  Congenital (neurofibromatosis, tubular sclerosis) 
  9.  Carcinoma with lymphatic spread 
  10.  CHF 

 D. Interstitial Pneumonias 
  1. Affects the supportive structure of the alveolar walls and terminal airways 
  2. Symptoms:  chronic dyspnea and nonproductive cough 
  3. PFT's:  Restrictive disease, decreased DLCO, decreased compliance 
  4. Sarcoidosis is most common cause of interstitial pneumonia 

 E. Nomenclature: 
  1. UIP (Usual Interstitial Pneumonia) 
   a. thickened alveolar wall with fibrosis and an inflammatory exudate 
  2. DIP (Desquamative Interstitial Pneumonia) 
   a. large # of macrophages  in the alveoli 
   b. very responsive to steroids because underlying lung architecture is intact 
  3. LIP (Lymphocytic Interstitial Pneumonia) 
   a. Lymphocytes accumulate around the bronchioles and blood vessels 
   b. may have a monoclonal gammopathy which may be detectable via serum electrophoresis 
   c. unpredictable response to steroids 
   d. may go unto lymphoma of the lung 
   e. other causes  lymphocytic infiltrate AIDS, sarcoidosis, Sjogren's 
  4. GIP (Giant Cell Interstitial Pneumonia) 
   a. look for exposure to organic dust oral pneumonias 
   b. viral pneumonias 
  5. BO (Bronchiolitis Obliterans) 
   a. variety of insults 
   b. unresponsiveness to steroids 
   c. associated with rheumatoid arthritis and connectiv  tissue disorders 
  6. BOOP (Bronchiolitis Obliterans Organizing Pneumonia) 
   a. plugs of fibrous tissue (Masson bodies) 
   b. many associations but, most are idiopathic 
   c. responsive to steroids 

 F. Hypersensitivity Pneumonitides 
  1. increase in T lymphocyte CD-8 (suppressor cell) in the lung secondary to inhalation of organic antigens 
  2. Biopsy: noncaseating granulomas typically around terminal bronchioles with a mixed inflammatory infiltrate 

 G. Inorganic Pneumoconiosis 
  a. inhalation of nonorganic dusts and fibers 
  b. three most common: 
   1) silicone 
   2) coal dust 
   3) Asbestos 
  c. Asbestosis 
   1) characteristic pleural plaques in the chest wall and diaphragm on CXR 
   2) increases the risk of malignant mesothelioma 
   3) lung carcinoma increased synergistically with asbestos and tobacco 
   4) affects lower lobes/ pleural thickening 
   5) Biopsy: ferruginous bodies 
   6) long delay between exposure and onset of disease 

 H. Connective Tissue Diseases 
  a. almost all connective tissue disorders have a pulmonary component 
  b. Biopsy: does not aid in differentiating between diseases 

 I. Pulmonary Drug Toxicity 
  a. Abx: Bleomycin, sulfa 
  b. Alkylating Agents: Cyclophosphamide, Melophan 
  c. Immunosuppressive: Immuran, Methotrexate 
  d. Antiarrhythmic: Procainamide, Amiodarone(foamy cells) 
  e. Diuretic: HCTZ 
  f. Antihypertensitive: Hydralazine 
  g. Opiates: Methadone, Heroin, Propoxyphene 

 J. Chronic Eosinophilic Pneumonia 
  a. elements of interstitial & acinar infiltrates 
  b. steroid response in the early phase 
  c. diagnosis by blood Cx and biopsy with eosinopiles 
  d. Biopsy Charcot Leyden crystals 

 K. Pulmonary Vasculitides & Granulomas 
  a. rule out infection before beginning steroids 

 L. Idiopathic 
  a. 20-30% of interstitial lung disease 
  b Sx: dyspnea, cough, clubbing and arthralgias 
  c. Bx: collagen deposition with inflammatory responsive 
  d. 4- 5 yr. survival 
  e. DIP pattern has a better response time