• Pseudomonas aeruginosa is a moderately-sized Gram-negative bacillus.
• Possess a monotrichous (def) arrangement of flagella.
• Pseudomonas is typically aerobic (def) but can grow under select anaerobic conditions (def).
• Does not ferment sugars.

Habitat and Source

• A ubiquitous bacterium found in soil, water, vegetation, decaying organic matter, throughout the hospital environment, and frequently carried in the respiratory and intestinal tracts of hospitalized patients and immunocompromized hosts.

Epidemiology

• Pseudomonas aeruginosa is also an opportunistic pathogen. It is a common cause of nosocomial infections (def) and can be found growing in a large variety of environmental locations. In the hospital environment, for example, it has been isolated from drains, sinks, faucets, water from cut flowers, cleaning solutions, medicines, and even disinfectant soap solutions. It is especially dangerous to the debilitated or immunocompromised patient.
• P. aeruginosa is responsible for 12 percent of hospital-acquired urinary tract infections, 16 percent of nosocomial pneumonia cases, and 10 percent of the cases of septicemia.

Clinical Disease

• Pseudomonas causes a variety of opportunistic infections including urinary tract infections, wound infections, pneumonia, and septicemia.
• P. aeruginosa is a significant cause of burn infections with a 60 percent mortality rate.
• P. aeruginosa also colonizes and chronically infects the lungs of people with cystic fibrosis.

From Pseudomonas aeruginosa Infection, by Samer Qarah, MD, Fellow, Department of Internal Medicine, Division of Pulmonary and Critical Care, The Brooklyn Hospital Center and Cornell University; Burke A Cunha, MD, Professor of Medicine, State University of New York at Stony Brook School of Medicine; Chief, Infectious Disease Division, Vice-Chair, Department of Internal Medicine, Winthrop-University Hospital; Pratibha Dua, MD, Staff Physician, Department of Internal Medicine, The Brooklyn Hospital Center; Klaus-Dieter Lessnau, MD, FCCP, Clinical Assistant Professor of Medicine, New York University School of Medicine; Medical Director, Pulmonary Physiology Laboratory, Department of Medicine, Section of Pulmonary Medicine, Lenox Hill Hospital.