Acute exacerbation of interstitial lung diseases (ILD) is an acute, clinically significant respiratory 
deterioration, typically less than 1 month in duration, together with high resolution computerized 
tomography(HRCT) imaging showing new bilateral glass opacity and/or consolidation superimposed 
on a background pattern consistent with fibrosing ILDs. Aim of the work: To illustrate the clinical 
and radiological features of acute exacerbation of interstitial lung diseases. patient and Methods: 50 
ILDs patients with acute exacerbation and 30 stable ILDs patients were included. History ,Spirometry,
arterial blood gases(ABGs) and HRCT chest were done for all subjects. Results: there was a
significant worsening in respiratory signs and symptoms (including dyspnea , hypoxemia and fever), 
also there was decline in forced vital capacity (FVC) and partial pressure of oxygen (PaO2) in acute 
exacerbation of ILDs. Conclusions: The diagnosis of AE in ILDs is reliant on clinical and 
radiological findings.