Pleural Empyema Due to Bacteroides

Bacteroides are gram negative, anaerobic, pleomorphic rods which may vary from minute coccoid to bacillary rods to long filamentous forms. They are found in the intestinal tracts and on mucous membranes of warm blooded animals.¹Bacteroides have been implicated as having human pathogenicity since 1897 when Veillon and Zuber ² found such anaerobic organisms in gangrenous suppuration. In 1945 Smith and Ropes³ reviewed the literature of Bacteroides infections and added 20 cases, three of which were fatal. Other studies have established that Bacteroides are pathogenic ⁴ and such infections, although more frequently found in debilitated or aged persons, also occur in young seemingly healthy individuals.⁵ In addition to causing abdominal abscesses and peritonitis (characteristically as a postoperative complication),⁶ they have been reported as a cause of lung abscesses ⁷ and pleural empyema.^8-10 Diagnosis of such infections is sometimes missed because these pleomorphic organsims are often difficult to identify on direct