This document discusses Pseudomonas aeruginosa, a common nosocomial pathogen. It is a gram-negative, aerobic bacterium that is motile by flagella and produces pigments. It can be found in moist environments like hospitals. Specimens may include wound discharge, sputum, blood, urine or CSF. On gram stain it appears as gram-negative rods, and in culture it forms smooth, fluorescent colonies with a grape-like odor and does not ferment lactose. It is oxidase and catalase positive.

2. Introduction
 Medically important Pseudomonas:
P. aeruginosa
 Commonly present in moist environments in
hospitals.
 It is primarily a nosocomial pathogen.

3.  Gram-negative rods.
 Motile by polar flagella.
 aerobics.
 Grow well at 42⁰C.
 Non-lactose fermenting

4. Pathogenesis

6.  can produce pigments, such as:
 Pyocyanine (blue-green)
 Pyoverdin (fluorescent yellow- greenish
pigment)
 Pyorubrin (red)
 Pyomelanin (brown)

7. Specimen:
 Wound discharge
 sputum
 Blood
 Urine
 CSF

8. Gram stain
 Gram negative rod
undistinguished from
enerobacteriaceae

10.  Form smooth and round colonies.
 Fluorescent greenish colour.
 production of fruity odor (grape-like) .
 Inability to ferment lactose.

11.  Colonies are smooth, large, translucent
 Greenish blue diffusible pigment

12.  Grayish colonies
 Many are haemolytic
(beta hemolysis).
This picture shows Pseudomonas
aeruginosa (on the right) and Shigella
dysenteriae (on the left) in blood agar.

13.  Non-lactose fermenting (colourless colonies)

14. Pseudomonas aeruginosa fluorescence under UV
illumination

16. Oxidase test
 Oxidase positive
Catalase test
 Catalase positive