Pseudomonas is a genus of gamma proteobacteria, belonging to the larger family of pseudomonads.
The genus Pseudomonas includes bacteria formerly classified in the genera Chryseomonas and Flavimonas. Other bacteria previously classified in the genus Pseudomonas are now classified in the genera Burkholderia and Ralstonia.
Pseudomonas aeruginosa is a common bacterium which can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has thus colonized many natural and artificial environments.
Because it thrives on most surfaces, this bacterium is also found on and in medical equipment, including catheters, causing cross-infections in hospitals and clinics. It is implicated in hot-tub rash In humans, possibly due to excessive warmth and moisture of the skin causing increased susceptibility to infection. Theoretically the same would be possible in dogs who spend a great deal of time in the pool or hot tub.
Pseudomonas bacteria use a wide range of organic material for food; in animals, the versatility enables the organism to infect damaged tissues or people with reduced immunity. The symptoms of such infections depend on the location of the infection, but most any tissue of the body can be infected. Although infections in dogs and cats can include not only skin and ears, but also respiratory tract and urinary tract, we will focus on the skin and ears.
The most common veterinary dermatological disorder in which Pseudomonas plays a role must be otitis (ear infections). There must be some characteristics of the canine ear (moreso than the feline ear) that make it a suitable target for Pseudomonas. The bacteria appears to possess significant virulence factors judging by difficulty in clearing a Pseudomonas otitis. However, there are some important features, that if addressed, make clearing a Pseudomonas otitis more likely.
How to make the ear less supportive of Pseudomonas infection:
Prevention is key. Avoid using old tubes of medications or cleansers that may have become contaminated from treating past infections or infections in other pets. Pseudomonas are often resistant to antiseptics and will not be killed by any antibiotic to which they are resistant – they will happily exist in an old bottle of medication or cleanser.
When your pet is boarded or if she/he needs ear therapy, insist that your pet’s own bottle of cleanser be used, do not let a “community” bottle of cleanser or ear medicine be used for your pet’s ears. Pseudomonas are not killed by many antiseptics.
Insist on a new disposable otoscope (the tool used to examine the ear) cone (the cone-shaped plastic part of the otoscope that is inserted in the ear) be used for your pet’s ear. Reusable cones or ear endoscopes are OK as long as fresh antiseptic, tested for the ability to kill Pseudomonas are used prior to placing in your dog’s ears. Studies often find Pseudomonas bacteria can survive in many of the soapy liquid antiseptic trays often used to store reusable otoscope cones.
What you can do if your pet has Pseudomonas otitis:
Control your pet’s allergies. Allergies can cause damage to the ear making it a good “home” for Pseudomonas to take up residence and allergies are the most common cause behind recurring ear infections in adult pets. Severe uncontrolled allergy can make ear infections impossible to resolve.
Follow your veterinarian’s instructions closely with regard to ear therapy:
Be sure to use ear medications as directed. If you run out of ear medicine or cleanser sooner than planned, ask for a refill right away. Ask for a demonstration if you are not sure how to administer the ear medicine to your pet. Use all oral antibiotics as directed.
Be sure to keep followup appointments for ear infections. Most pets act better before the ear infection is truly resolved. Do not use your pet’s behavior with regard to its ears as an indication the infection is resolved. Otherwise you may find a situation in which infections recur frequently enough to cause permanent damage to the ear and the need for ear surgery.
Pseudomonas skin infections
Occasionally Pseudomonas can cause infections of the skin of dogs and cats. Most often this happens in areas of skin that are damaged or in immunosuppressed pets. Often the skin is damaged enough from chronic Staph infections that Pseudomonas bacteria are able to infect the skin also.