• Generalized connective tissue disorder
  
• Tightening, induration and thickening of the skin, Raynaud’s phenomenon, vascular abnormalities, musculoskeletal manifestations, visceral involvement of lungs, heart, and kidneys
  
• Radiography: symmetric basal reticulonodular pattern (“lace like) with cysts (1 to 30 mm) and/or honeycombing, small volume lungs, air-filled esophagus
  
• HRCT best modality to show ground glass, reticular, micronodular opacities, honeycombing, cysts and traction bronchiectasis
  
• Complications: Renal failure, pulmonary artery hypertension.cardiac disease, lung cancer, (alveolar cell and adenocarcinoma), aspiration pneumonia, esophageal disorders, and follicular bronchiolitis, BOOP
  
• Antinuclear antibodies (100%)
  
• Prognosis, poor; 70% 5-year survival; cause of death usually aspiration pneumonia

Chest radiography

• Abnormal in 20% to 65%
  
• CXR may be normal with abnormal HRCT and PFTs
  
• Progression of fine basilar reticulation to coarse fibrosis
  
• Widespread symmetric basal reticulonodular pattern with cysts (1 to 30 mm) and/or honeycombing
  
• Decreased lung volume
  
• Elevated diaphragms may also be due to diaphragmatic muscle atrophy and fibrosis
  
• Dilated, air-filled esophagus without an air-fluid level best seen on lateral CXR; air in the stomach (75%), esophageal dysmotility (50%)
  
• Pleural thickening and effusions, rare (<15%)
  
• Musculoskeletal
  
  • Erosions of ribs, superior aspect, posterolaterally, (<20%)
    
  • Absorption distal phalanges, tuft calcification
    
• GI
  
  • Dilated, aperistaltic esophagus

CT/HRCT

• HRCT best modality to show abnormalities
  
• Peripheral posterior basilar distribution
  
• Ground glass opacities, fine reticular pattern, septal lines, subpleural long lines, intralobular linear opacities, parenchymal and subpleural micronodulation
  
• Honeycombing, traction bronchiectasis, subpleural cysts
  
• Lymphadenopathy (60%)
  
• Esophageal dilatation (80%)
  
• Pleural thickening (pseudoplaques, 33%)
  
• Pulmonary artery hypertension, (<50%) may be separate from ILD

• Scleroderma features
  
  • CREST
    
  • MCTD
    
  • Diffuse fasciitis and eosinophilia
    
  • Carcinoid syndrome
    
  • Drug reaction
    
  • Chronic graft versus host disease
    
• Radiographic findings
  
  • Usual interstitial pneumonitis
    
  • Asbestosis
    
  • Rheumatoid arthritis
    
  • Drug reaction
    
  • Sarcoid
    
• Differentiation
• Identical to UIP, however, esophagus usually dilated, look for hand films and soft tissue calcification

• Generalized connective tissue disorder
  
• Lung is fourth most common organ involved after skin, blood vessels, esophagus
  
• Persistent overproduction and tissue deposition of collagen and related macromolecules
  
• Fibroblast proliferation, capillary endothelial damage causing increased vascular permeability and alveolitis
  
• Interstitial fibrosis subpleural regions of lower lobes that can progress to end stage lung (identical to UIP)
  
• Follicular bronchiolitis and BOOP
  
• Vascular changes in small vessels – intimal proliferation, medial hypertrophy, myxomatous changes may lead to pulmonary hypertension
  
• Pleural fibrosis, infrequently identified radiographically
  
• Pathogenesis
  Genetic susceptibility, and/or environmental factors
• Antinuclear antibodies (100%)
  
• Antitopoisomerase I (30%), anti-RNA polymerase III and antihistone antibodies associated with interstitial lung disease
  
• Anticentromere antibodies in CREST variant associated with absence of interstitial lung disease
  
• Reduced circulating T-suppressor cells and natural killer cells which can suppress fibroblast proliferation

• Usual onset age 30 to 50; female to male ratio, 3:1; whites=blacks
  
• Uncommon 1.2/100,000
  
• Tightening, induration and thickening of the skin, Raynaud’s phenomenon, vascular abnormalities, musculoskeletal manifestations, visceral involvement of lungs, heart, and kidneys
  
• Major criteria: involvement of skin proximal to metacarpophalangeal joints
  
• Minor criteria: sclerodactyly, pitting scars, loss of finger tip tufts, bilateral pulmonary basal fibrosis
  
• Most common presentation is Raynaud’s phenomenon, (up to 90%), tendonitis, arthralgia, arthritis
  
• Lung disease indolent and progressive
  
• Complications: renal failure, pulmonary artery hypertension and cardiac disease, lung cancer, (alveolar cell and adenocarcinoma), and aspiration pneumonia
  
• Esophageal dysmotility, gastroesophageal reflux, esophageal candidiasis, and stricture, weight loss
  
• Dyspnea (60%), cough, pleuritic pain, fever, hemoptysis, dysphagia
  
• Most patients have abnormal PFTs: restrictive defect, decreased diffusion capacity, obstructive defect without smoking history
  
• BAL varies from lymphocytic to neutrophilic alveolitis (50%)
  
• Treatment supportive
  
• Renal failure may actually improve musculskeletal disease
  
• Prognosis, poor; 70% 5-year survival; cause of death usually aspiration pneumonia
  

Taormina VJ, Miller WT, Gefter WB, et al. Progressive systemic sclerosis subgroups: variable pulmonary features AJR 137:277-285, 1981
Schurawitzki H, Stiglbauer R, Graninger W, et al. Interstitial lung disease in progressive systemic sclerosis: high-resolution CT versus radiography Radiology 176:755-759, 1990
Bhalla M, Silver RM, Shepard JA, et al. Chest CT in patients with scleroderma: prevalence of asymptomatic esophageal dilatation and mediastinal lymphadenopathy AJR 161:269-272, 1993