Colonies of Pseudomonas aeruginosa and Enterococcus faecalis on Tryptic Soy Agar. Cultivation 48 hours in an aerobic
P.aeruginosa: oxidase: + catalase: + pigment: pyocyanin (blue-green) and pyoverdine (yellow-green, fluorescent)
E.faecalis: oxidase: - catalase: - pigment: non-pigmented
An opportunistic, nosocomial pathogen of immunocompromised individuals, P. aeruginosa typically infects the pulmonary tract, urinary tract, burns and wounds.
It is the most common cause of infections of burn injuries and of the external ear (otitis externa), and is the most frequent colonizer of medical devices (e.g., catheters). Pseudomonas can, in rare circumstances,
cause community-acquired pneumonias, as well as ventilator-associated pneumonias, being one of the most common agents isolated in several studies.