acute lobar pneumonia, a form of pneumonia that can involve one or more lobes of the lung, characterized by a sudden onset, chills, fever, difficulty breathing, pleuritic chest pain, dry cough, rust-colored (blood-stained) sputum, and consolidation of the serofibrous fluid exuded by the alveoli. The condition results from infection by a virulent type of Streptococcus pneumoniae.
