Empyema caused by Kingella denitrificans and Peptostreptococcus spp. in a patient with bronchogenic carcinoma.

Empyema caused by Kingella denitrificans and Peptostreptococcus spp. was diagnosed in a patient with bronchogenic carcinoma. This appears to be the third report providing evidence of a pathogenic role for K. denitrificans, and the first concerning infection in the pleural space and in a patient with underlying immunosuppressive disease. K. denitrificans should be added to the list of fastidious gram-negative bacteria associated with opportunistic infections in the compromised host.