What Is Pseudomonas Aeruginosa?

Medically Reviewed by Neha Pathak, MD on October 27, 2022
5 min read

Pseudomonas aeruginosa is a bacteria that's commonly found in the environment, for example in soil and water. It can be spread to people in health care settings through contaminated surfaces, hands, and equipment. It can cause serious infections in certain people. Some healthy people even have strains of it growing on their skin in moist parts of their body, like their armpits or genital area. This can be called a pseudomonas infection.

If you're in good health, you may not get sick from it. Other people only get a mild skin rash or an ear or eye infection. But if you're sick or your immune system is already weakened, pseudomonas can cause a severe infection. In people with cystic fibrosis, cancer, or burns, it can be life-threatening. It is one of the top causes of infections people get from being in hospitals.

You can get pseudomonas infections in many ways. It can grow on fruits and vegetables, so you could get sick from eating contaminated food. It also thrives in moist areas like pools, hot tubs, bathrooms, kitchens, and sinks.

The most severe infections occur in hospitals. Pseudomonas aeruginosa can easily grow in humidifiers and types of medical equipment -- catheters, for instance -- that aren’t properly cleaned. If health care workers don’t wash their hands well, they can also transfer the bacteria from an infected patient to you.

Your risk of pseudomonas infection also goes up if you:

  • Have a wound from surgery

  • Are being treated for burns

  • Use a breathing machine, catheter, or other medical device

  • Have diabetes or cystic fibrosis

  • Have a disorder that weakens your immune system, such as HIV

Take medications that suppress your immune system, like those that treat cancer

Pseudomonas aeruginosa can be found in:

  • Drains and plumbing parts
  • Household cleaning products
  • Hospital or clinic equipment
  • Water
  • Soil

Symptoms depend on where the Pseudomonas aeruginosa is. Pseudomonas infections can infect any part of your body, such as your blood, lungs, stomach, urinary tract, or tendons. Pressure sores, wounds, and burns can also become infected.

Places where infection occurs -- and their signs -- may include:

  • Ears: pain and discharge
  • Skin: rash, which can include pimples filled with pus
  • Eyes: pain, redness, swelling
  • Bones or joints: joint pain and swelling; neck or back pain that lasts weeks
  • Wounds: green pus or discharge that may have a fruity smell
  • Digestive tract: headache, diarrhea
  • Lungs: pneumonia; severe coughing and congestion
  • Urinary: urinary tract infections

Fever is also often a sign of a severe pseudomonas infection.

If your doctor suspects you have Pseudomonas aeruginosa, they’ll take a sample of your blood or another body fluid and send it to a lab to be tested. The results may also help them decide which types of antibiotics will work best to cure the infection.

If you have a mild infection, your doctor can prescribe a course of antibiotics. Depending on where your infection is, this medicine could be in the form of a cream, eye drops or ear drops, or pills you take by mouth.

A severe infection may require weeks of antibiotics that you’ll be given through an IV. Every pseudomonas bacteria is slightly different, and strains are constantly changing, so these types of infections can be hard to treat. Many times, you may need to take more than one kind of antibiotic.

More recently, scientists have found that bacteriophages, which are viruses that infect bacteria, may be useful for healing from Pseudomonas aeruginosa infections. They have been used to treat other conditions. Research in labs (but not in humans) shows that these are a few possible solutions:

  • Ceftolozane-tazobactam
  • Ceftazidime-avibactam
  • Imipenem-relebactam
  • Cefiderocol
  • Cefepime-taniborbactam
  • Cefepime-zidebactam
  • Cefepime-beta-lactams inhibitor (BLI) combinations like cefepime-taniborbactam and cefepime-zidebactam
  • Meropenem-nacubactam

There's some research on plant-derived compounds to treat the infection. It focused mostly on how the compounds could interrupt biofilms, which protect bacteria and lead to resistance. Medical grade Manuka honey has shown promise to interrupt biofilms in wounds. Efforts to combat Pseudomonas aeruginosa are mostly focused on other possible solutions.

It can be. Pseudomonas aeruginosa is what's called a multidrug-resistant and extensively drug-resistant bacteria. That means it can be hard to treat because it may not respond to the antibiotics we have. In other words, the antibiotics aren't strong enough to kill the infection. The World Health Organization identified it as one of three bacteria that need to be better managed. The CDC lists it as a serious threat.

If initial treatment with an antibiotic or antibiotics doesn't work, the infection may be resistant to those treatments. People with cystic fibrosis may be prone to recurrent infections with Pseudomonas aeruginosa. Some people get a secondary infection with Clostridioides difficile, which can be common when people take antibiotics.

You can lower your risk of getting sick by trying to avoid coming into contact with this type of bacteria. Try these simple tips to keep these nasty germs at bay:

  • Wash your hands often. This is the best way to avoid getting pseudomonas. If you’re in the hospital, make sure that doctors and nurses always clean their hands before touching you, too.

  • Rinse fruits and vegetables before eating. Even salad greens should be given a good wash.

  • Clean your water bottles. Sterilize with boiling water between each use.

  • Avoid unclean pools and hot tubs. Pseudomonas will thrive in them unless they’re cleaned often and the chlorine and pH are well-controlled.

  • Ask questions about your medical care. Talk to your doctor if you have worries about getting infected. Ask about medical equipment you’re using -- whether it's necessary and how often it’s cleaned.

  • Take care of your health. If your doctor has prescribed medicine to manage a health condition, take it exactly as prescribed. Don’t skip a dose. After surgery, be on the lookout for signs of infection. If you run a fever, have pain, or see redness or discharge at your surgery site, call your doctor right away.

In most cases, antibiotics can clear a Pseudomonas aeruginosa infection, but it’s important to follow your doctor’s instructions and focus on prevention. If one course of antibiotics doesn't completely get rid of the bacteria that’s causing your infection, you may need to take them fairly regularly to keep the infection under control. It is extremely hard for people with cystic fibrosis to beat the infection. It is the leading cause of death for people with the disease.