Proteus mirabilis is a bacterium found in soil, water, and as a normal part of the human intestinal flora. While typically harmless in the gut, it can cause infections when it enters other parts of the body.
Understanding Proteus Mirabilis
Proteus mirabilis is a Gram-negative, rod-shaped bacterium that can survive with or without oxygen. It exhibits distinctive “swarming” motility, moving across surfaces in a coordinated manner. This movement is facilitated by numerous flagella, which are propeller-like appendages.
Proteus mirabilis produces an enzyme called urease. Urease breaks down urea, a waste product in urine, into ammonia and carbon dioxide. This process increases urine pH, making it more alkaline, which contributes to the formation of certain kidney stones.
Infections Caused
Proteus mirabilis is a common cause of urinary tract infections (UTIs), especially those associated with long-term catheter use. It accounts for a significant percentage of catheter-associated UTIs. Symptoms include painful or frequent urination, lower abdominal pain, cloudy urine, and sometimes blood in the urine.
The bacterium’s urease production can lead to struvite stone formation. These kidney stones can grow large, potentially obstructing the urinary tract and acting as a persistent source of infection. Beyond UTIs, Proteus mirabilis can also cause wound infections and, in more severe instances, bacteremia.
Identifying and Treating Infections
Diagnosing a Proteus mirabilis infection involves laboratory urine tests. A urine culture is the most definitive method to confirm Proteus bacteria. Urine analysis can reveal white blood cells (pyuria) or bacteria (bacteriuria). A urine pH above 7.0 suggests a Proteus infection due to its urease activity.
Treatment for Proteus mirabilis infections primarily involves antibiotic therapy. The specific antibiotic chosen depends on infection severity and bacterial susceptibility. Sensitivity testing, performed after a culture, guides the selection of the most effective antibiotic. For uncomplicated UTIs, a short course of oral antibiotics may be prescribed. More severe infections, such as those with kidney stones or bacteremia, may require intravenous antibiotics and surgical intervention for stone removal.
Preventing Proteus Mirabilis Infections
Preventing Proteus mirabilis infections focuses on general hygiene and careful risk factor management. For catheter users, proper catheter care is important to reduce infection risk. Minimizing catheterization duration is also a key strategy, as long-term use increases infection likelihood.
Maintaining adequate hydration helps prevent UTIs. These measures reduce opportunities for Proteus mirabilis to colonize and cause infection, particularly in the urinary tract.