Clinical approach to acute interstitial lung diseases

A subset of patients who present with acute respiratory symptoms will develop acute hypoxic respiratory failure with bilateral lung infiltrates and may fulfill clinical criteria for the acute respiratory distress syndrome. There is a wide variety of well-known etiologies, including infection/sepsis, shock, trauma, aspiration, oxygen toxicity and many others. A few cases occur without an apparent cause or underlying context such as acute interstitial pneumonia (AIP), cryptogenic organizing pneumonia (COP), acute eosinophilic pneumonia (AEP), while others occur as a rapid deterioration of previously diagnosed or undiagnosed chronic interstitial lung disorders (ILD), such as idiopathic pulmonary fibrosis (IPF), nonspecific interstitial pneumonia (NSIP), hyper-sensitivity pneumonitis (HP), collagen vascular disease with ILD (CVD-ILD). These patients need a correct setting and management, especially regarding their oxygenation. It’s very important to identify cases that have a treatable or potentially reversible cause, and distinguish them from those in whom the etiology is unknown and the response to therapy is likely to be poor. Primarily pulmonary infection, heart failure, pulmonary thromboembolism, drug toxicity and collagen vascular diseases should be excluded. The most important diagnostic tools are clinical features, radiologic pattern, bronchoalveolar lavage, transbronchial lung biopsy and surgical biopsy. Fast diagnosis and prompt beginning of therapy are of pivotal importance