Pseudomonas Infections

Pseudomonas is a small, gram-negative bacillus that vimarily produces nosocomial infections, superinfactions of various parts of the body, and a rare disease called melioidosis. The most common infections associated with Pseudomonas include skin in drug enions (such as burns and pressure ulcers). urinary tract infections, infant epidemic diarrhea and other diarrheal illnesses, bronchitis, pneumonia, bronchiectasis, meningitis, corneal ulcers, mastoiditis, otitis externa. and otitis media. This bacillus is especially, associated with bacteremia, endocarditis, and osteomyelitis in drug addicts.

In local Pseudomonas infections, treatment usually is successful and complications rare. However, in patients with poor resistance to infection (for example, premature infants, elderly people, and persons with debilitating disease, burns, or wounds), septicemic Pseudomonas infections are considered serious. In some patients they may even cause death.

Causes

The most common species of Pseudomonas is P. aeruginosa. Other pathogenic species include P. maltophilia, P. cepacia, P. fluorescens, P. testosteroni, P. acidovorans, P. alcaligenes, P. stutzeri, P. putrefaciens, and P. putida.

These organisms frequently are found in facility, liquids that have been allowed to stand for a long time, such as benzalkonium chloride, hexachlorophene soap, saline solution, water in flower vases, and fluids in incubators, humidifiers, and respiratory therapy equipment. Outside the facility, Pseudomonas skin infections have been associated with the use of contaminated whirlpools, hot tubs, spas, and swimming pools.

In elderly patients, Pseudomonas infection usually enters through the genitourinary tract; in infants. Pseudomonas infection usually enters through the umbilical cord, skin, or GI tract.

Signs and Symptoms

As with other infections, symptoms include fever, chills, and the production of purulent matter in infected wounds.

Diagnostic tests

Diagnosis relies on isolation of the Pseudomonas organism in blood, cerebrospinal fluid, urine, exudate, or sputum culture.

Treatment

In the debilitated or otherwise vulnerable patient with clinical evidence of Pseudomonas infection, treatment should begin immediately, without waiting for laboratory test results. Most types of P. aeruginosa diseases are treated with one or more antibiotics to which the organism is sensitive. Antibiotic treatment includes aminoglycosides, such as gentamicin or amikacin, combined with a Pseudomonas-sensitive penicillin, such as ceftazidime or imipenem/cilastatin. Such combination therapy is necessary because Pseudomonas quickly becomes resistant to penicillin derivatives alone.

Pulmonary infections, particularly in individuals with cystic fibrosis, require aggressive pulmonary toiletry and bronchial lavage. Aerosolized antibiotics may also be used successfully in some cases. Lung transplantation may also be an option.

Surgical intervention is often required for Pseudomonas infections. Debridement of dentiled tissue, such as in otitis externa that is malignant, chronic osteomyelitis, or osteochondritis, is necessary. Drainage of pus areas is necessary. Affected heart valves require replacement. Necrotizing enterocolitis requires bowel resection, and urinary tract obstruction necessitates surgery.

With proper treatment, most infections with P. aeruginosa are curable. Extremely high mortality is associated with conditions that involve bacteremic pneumonia, septicemia, brain-wound sepsis, and meningitis. Chronic conditions, such as contiguous osteomyelitis, malignant otitis externa, and lower respiratory tract infections in patients with cystic fibrosis are difficult to eradicate and may end in death after long-term illness.