The histologic entity that has the worst prognosis in interstitial lung disease is:

Ans: c (Acute interstitial pneumonia)Ref: Rosai and Ackerman's Surgical Pathology 9th ed Pg. 377, Harrison 18th ed chp 261Acute Interstitial Pneumonia (Hamman-Rich Syndrome)* A fulminant form of lung injury characterized by idiopathic ARDS and organizing diffuse alveolar damage by lung biopsy.* The onset is usually abrupt following a prodromal illness.* CXR - Diffuse, bilateral, air-space opacification.* HRCT - bilateral, patchy, symmetric areas of ground-glass attenuation & areas of air-space consolidation. A predominantly subpleural distribution may be seen.* The mortality rate is high (>60%), most patients die within 6 months.* Treatment is supportive, glucocorticoid therapy role not clear.