Pseudomonas aeruginosa is a naturally occurring bacterium that lives in soil, water, and plants. It is harmless in the environment but can cause opportunistic infections when it enters the human body, especially in people with weakened immune systems.

Pseudomonas may invade organ systems, including the blood, lungs, soft tissue (skin, muscles, and tendons), and other parts of the body. The symptoms depend on the site of infection.

This bacterium does most of its damage in vulnerable populations, such as people who have just had surgery and those who are immunocompromised (have a weakened immune system), such as people with human immunodeficiency virus (HIV), AIDS, or diabetes. Infections often are acquired in hospitals or other healthcare facilities.

This article will discuss the symptoms of infection by Pseudomonas aeruginosa, complications and groups who are most at risk, and when to see a healthcare provider.

Frequent Symptoms

Pseudomonas infection symptoms depend on where in the body they occur. Pseudomonas can cause infections in the following organs:

  • Ear (external otitis or swimmer’s ear)
  • Skin (ecthyma gangrenosum): Pseudomonas enters the skin via pressure sores, burns, and surgical wounds or from the bloodstream in a person with bacteremia. It may also cause folliculitis (infection of the hair follicles).
  • Lungs: Pseudomonas may produce severe pneumonia, often in people who are hospitalized and already sick and immunocompromised. It can cause chronic lung infections in people with cystic fibrosis (an inherited condition), bronchiectasis (permanent widening of the airways), or chronic obstructive pulmonary disease.
  • Bloodstream (bacteremia)
  • Bone and joint infections: These are often are the result of bacteria spreading to the skin, bone, and joints from intravenous (IV) drug use or infected surgical wounds or wounds from injuries.

Therefore, Pseudomonas infections are characterized by a wide range of symptoms. General nonspecific symptoms (those that are common among many illnesses) include:

  • FeverSweatingChillsCoughFatigue

More specific symptoms based on the affected organ include:

  • Ears: Pain, edema (swelling), tenderness, and discharge
  • Skin: Abscess (a lump of infection), rash, pus, skin ulcer, necrotizing tissue (skin turning black, indicative of dying tissue)
  • Bones or joints: Loss of mobility, joint or back pain, swelling, and pain or warmth in the affected area
  • Wounds: Productive discharge or crust on wounds (often yellow-green), may have a sweet or bad smell
  • Digestive tract: Typhlitis (intestinal infection in a person with low white blood cells due to treatment) symptoms of abdominal pain, abdominal distention, and diarrhea
  • Lungs: Shortness of breath, chest pain, productive cough (with white, yellow, or greenish mucus), and congestion
  • Urinary tract: Painful urination, unpleasant or sweet-smelling urine, urgency, cloudy urine

Rare Symptoms

Shortness of breath, fast heart rate, weak pulse, confusion, fever, shivering, or intense pain are symptoms of septic shock, a whole-body reaction to a bloodstream infection. This is a medical emergency.

Rarely, the heart valves may be infected, especially in people who use drugs intravenously. Bacteria from dirty needless can enter the bloodstream, where they travel to the heart and infect the heart valves, a condition called endocarditis.

A new murmur (abnormal heart sound) in a person who uses IV drugs can raise suspicion of Pseudomonas-related endocarditis. 

Complications/Subgroup Indications

Untreated, undertreated, or recurrent Pseudomonas infections can lead to more widespread infection, such as sepsis, which is potentially fatal. Higher-risk populations that are more likely to experience severe complications include:

  • People who have weakened immune systems (from conditions such as cancer, HIV/AIDS, organ transplant, and diabetes)People who have chronic wounds that require frequent wound carePeople who are hospitalized, particularly for a week or more (especially those on ventilators, who use catheters, or who have severe burn wounds)

Of note, antibiotic resistance is growing within the Pseudomonas species. These bacteria are finding new ways to avoid dying from even the most powerful and historically effective antibiotics.

When to See a Healthcare Provider/Go to the Hospital

See a healthcare provider if you have any skin wound showing signs of infection, such as a discharge, warmth, or lack of healing. Seek care If you have signs of a lung infection, such as fever, productive cough, or shortness of breath.

If you are in the hospital or under care for a condition that weakens your immune system, talk to your healthcare provider about what symptoms to report that may indicate an infection.

If you have a high fever, severe shortness of breath, or purulent discharge at the site of possible infection, you are at higher risk of your local Pseudomonas infection becoming more widespread. Systemic bacterial infection (sepsis) can cause organ failure and is potentially fatal. Therefore, seek immediate medical attention.

Summary

Pseudomonas aeruginosa is a bacterium that lives in soil, water, and plants. It is harmless in the environment, but it can cause opportunistic infections in people with weakened immune systems or those who are hospitalized.

It can affect many different organs, such as the lungs, skin, urinary tract, and bones. Symptoms depend on the organ system affected.

 A Word From Verywell

Pseudomonas infections mostly affect immunocompromised populations, but anyone, even if completely healthy, can develop an infection from this bacterium. Simple injuries, like scraping your foot when you are outside, can lead to a Pseudomonas infection. You must clean these cuts.

Never take skin infections lightly, and be sure to check with a healthcare provider if you have questions or start to develop symptoms.