Abstract

A broad spectrum of noninfectious pathologies can masquerade pneumoniae and lead to important therapeutic and diagnostic problems. Many disorders, such as pulmonary infarction, cardiac failure, atelectasis, neoplastic and lymphoproliferative disorders, drug or exogenous agent (radiation, blood transfusion, toxic gases, etc.) reactions, pulmonary eosinofilic infiltrate syndromes, bronchiolitis obliterans with organizing pneumonia, acute respiratory distress syndrome, diffuse alveolar hemorrhage, systemic vasculitis (Wegener’s granulomatosis, antiglomerular basement antibody disease, etc.) and some conditions of uncertain etiology (histiositosis X, pulmonary alveolar proteinosis, idiopathic pneumonia syndrome etc.) may have clinical and radiologic features that overlap with infectious causes of pneumonia. For a good approach to patient presenting with fever and pulmonary infiltration, we reviewed noninfectious pathologies mimicking pneumonia and their diagnostic clues.