Lung abscess is necrosis of the pulmonary tissue and formation of cavities (more than 2 cm) containing necrotic debris or fluid caused by microbial infection. This pus-filled cavity is often caused by aspiration, which may occur during altered consciousness. Alcoholism is the most common condition predisposing to lung abscesses. Lung abscess is considered primary (60%) when it results from existing lung parenchymal process and is termed secondary when it complicates another process e.g. vascular emboli or follows rupture of extrapulmonary abscess into lung.