UTI caused by Proteus mirabilis

UTI caused by Proteus mirabilis

Urinary Tract Infections (UTI) are highly common across all ages, sexes, and socio economic backgrounds. Most of these infections, however, are caused by a few common bacteria which are normally found in the human urinary tract. Proteus mirabilis is one such bacteria which is often responsible for UTIs in both males and females. In this article, we will discuss what is Proteus mirabilis and how it causes urinary tract infections.

What is Proteus mirabilis?

Proteus mirabilis is a type of bacteria that lives in the human digestive and/or urinary tract. It is also found in the environment, though its primary niche is the human body. Proteus mirabilis are Gram-negative rod-shaped bacteria, meaning they are generally slender and have a tough outer layer that prohibits the transport of certain molecules through it. They also produce indole, a compound which helps them resist antibiotics. Besides UTIs, Proteus mirabilis can cause serious infections in the gastrointestinal tract, lungs, skin, and other organs.

How does Proteus mirabilis cause urinary tract infection (UTI)?

Urinary tract infections are generally caused when the bacteria enter the bladder or urethra of an individual. Proteus mirabilis is especially prone to causing UTIs because it is able to adhere to the urethral or bladder epithelial cells, and rapidly colonize the area. Furthermore, they produce proteases, which are enzymes that break down proteins, lipases, which are enzymes that break down fats, and urease, an enzyme that breaks down urea into ammonia and bicarbonate. This enzyme makes the urine alkaline enough to support their growth, and this enables them to colonize even more quickly. Proteus mirabilis are also able to produce biofilm, which is a polysaccharide matrix that helps them bind to surfaces and resist treatment.

Symptoms of UTI caused by Proteus mirabilis

The most common symptom for UTI caused by Proteus mirabilis is the presence of blood, pus or mucus in the urine. Other symptoms may include:

  • Burning sensation during urination
  • Pain in lower abdomen and sides
  • Increased frequency of urination
  • Strong urge to urinate
  • Fever and chills
  • Fatigue and nausea

How is UTI caused by Proteus mirabilis treated?

UTI caused by Proteus mirabilis is usually treated with antibiotics. However, because Proteus mirabilis is naturally resistant to antibiotics, the infection may return even after successful treatment. If the infection does return, an alternative antibiotic should be prescribed. In extreme cases, a urinary alkalinizing agent may be administered to ensure the pH of the urine is at an optimal level for the bacteria to thrive. It is also important to drink an adequate amount of fluids and urinate regularly to help flush out any potential infections.


Proteus mirabilis is one of the most common causes of urinary tract infections. It has the ability to colonize quickly, resist antibiotics, and produce biofilm which helps it bind to surfaces. It is important to recognize the symptoms of a UTI caused by Proteus mirabilis and to seek medical help if necessary in order to prevent recurrent infections. With proper treatment and lifestyle changes, UTI’s can be managed effectively.