Lung Abscess Secondary to Aseptic Pulmonary Infarction

Abstract

Eleven instances of lung abscess secondary to aseptic hemorrhagic pulmonary infarction were encountered in a recent study at Cleveland City Hospital (6). This complication especially interested us because in certain cases the symptoms and signs of lung abscess so dominated the clinical picture that the underlying infarct had been unsuspected, to be disclosed only at autopsy. The literature contains numerous articles on the subject of pulmonary infarcts, but only an occasional reference to possible occurrence of a secondary abscess in an infarct. It is well known that aspiration of infected material may cause a lung abscess; also, that septic emboli are almost certain to be followed by abscess formation. It appears, however, that aseptic pulmonary infarction as a cause of lung abscess is not generally appreciated. Indeed, Castleman (1) has said that superimposed infection of a pulmonary infarct is a rare coincidence. In discussing the pathogenesis of lung abscess, Lilienthal (7) pointed out that an infarct may be infected by the embolus itself or secondarily contaminated from the bronchial tree, so that an abscess is produced. Van Allen and his associates (12), working with dogs, were able to produce only an occasional lung abscess either by means of sterile emboli (bird shot) or by intrabronchial insufflation of infected material. When they combined both methods in the same animal, however, they produced abscesses with much greater frequency. They concluded that a certain percentage of all abscesses are produced in this manner, i.e., bronchogenic infection of an aseptic infarct. Cutler and Gross (2) pointed out that an infarct is an excellent site for the formation of an abscess, and that this is quite likely to occur if pathogenic organisms are present in the bronchial tree. Steinberg, Clark and de la Chapelle (10) reported four autopsied cases of empyema following necrosis of bland infarcts in patients with cardiac disease. Hollmann (4) described the case of an elderly woman with a large abscess in the left upper lobe, which proved at autopsy to be in the center of a large infarct. Marks (9) recorded two examples of pneumothorax following pulmonary infarction. Touroff (11) reported a single case of “infrapulmonary” empyema due to necrosis of an infarct. The empyema was successfully treated by rib resection and drainage. Kirklin and Faust (5) in 1930 observed that secondary abscesses may occur and obscure the clinical and roentgenologic picture. Gsell (3) also mentioned the possibility of secondary infection of a bland infarct with abscess formation or gangrene, and reported one case. Clinical Observations Some or all of the usual signs and symptoms of pulmonary infarction were present in every case in which a lung abscess eventually developed. These included hemoptysis, chest pain, dyspnea, pleural friction rub, and signs of consolidation.