Case Report Community-Acquired Pneumonia and Empyema Caused by Citrobacter koseri in an Immunocompetent Patient

Copyright © 2015 Miguel Angel Ariza-Prota et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Citrobacter species, belonging to the family Enterobacteriaceae, are environmental organisms commonly found in soil, water, and the intestinal tracts of animals and humans. Citrobacter koseri is known to be an uncommon but serious cause of both sporadic and epidemic septicemia and meningitis in neonates and young infants. Most cases reported have occurred in immunocompromised hosts. The infections caused by Citrobacter are difficult to treat with usual broad spectrum antibiotics owing to rapid generation of mutants and have been associated with high death rates in the past. We believe this is the first case described in the literature of a community-acquired pneumonia and empyema caused by Citrobacter koseri in an immunocompetent adult patient. 1