Peri-emphysematous lung infection.

The difficulty in classifying pulmonary infection within areas of bullous emphysema may have contributed to the lack of appreciation of this entity. This process is important to recognize because: (1) the clinical picture is usually benign:; (2) it may be confused with tuberculosis, fungal disease, and carcinoma of the lung; and (3) radiographic resolution may be slow. For these reasons, pneumonitis which occurs within emphysematous lung may have been previously considered as slowly resolving pneumonias. The development of air-fluid levels within bullae has been called "infected emphysematous bullae." We believe that this phrase is misleading since there are no bacteriologic data to support the presence of infection within the bullae containing fluid. In fact, direct sampling of intrabullous fluid has been rarely reported and, if obtained, has been generally negative for bacteria. Furthermore, the clinical course in our patients is alos not consistent with infection within a space. Once fiberoptic bronchoscopy has excluded an obstructing endobronchial lesion, the physician may patiently follow the anticipated gradual resolution. We suggest that the phrase, "periemphysematous lung infection" best describes these related clinical-radiological conditions.