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Proteus mirabilis is often isolated from the gastrointestinal tract, although whether it is a commensal, a pathogen, or a transient organism, is somewhat controversial 11). Catheter-associated urinary tract infections (CAUTIs) are also often polymicrobial 9), and Proteus mirabilis is one of the most common organisms present during polymicrobial urine colonization and infection 10). Indeed, catheter-associated urinary tract infection is the most common source of bacteremia in nursing homes, bacteremia involving Proteus mirabilis most frequently occurs following UTI or catheter-associated urinary tract infections compared to other sources of infection, and bacteremia and sepsis due to Proteus mirabilis carry a high mortality rate 8). Urinary tract infections (UTIs) and catheter-associated urinary tract infections (CAUTIs) involving Proteus mirabilis are typically complicated by the formation of bladder and kidney stones (urolithiasis) and permanent kidney damage 6), and may progress to bacteremia and potentially life-threatening sepsis 7). Proteus mirabilis is capable of causing symptomatic infections of the urinary tract including cystitis and pyelonephritis and is present in cases of asymptomatic bacteriuria, particularly in the elderly and patients with type 2 diabetes 5). These infections are common in long-term catheterized patients, such as those who reside in nursing homes and chronic care facilities, and may be of particular danger to spinal cord injury patients 4). While the Proteus mirabilis bacterium is capable of causing a variety of human infections, including those of wounds, the eye, the gastrointestinal tract, and the urinary tract, it is most noted for infections of the catheterized urinary tract, known as catheter-associated urinary tract infections 3). Urease production and robust swarming motility are the two hallmarks of this organism. Proteus mirabilis can be found in a wide variety of environments, including soil, water sources, and sewage, but it is predominantly a normal human and animal intestinal flora (along with Klebsiella species, and Escherichia coli) 2). Proteus mirabilis is well-known in clinical laboratories and microbiology survey courses as the species that swarms across agar surfaces, overtaking any other species present in the process. Proteus mirabilis is a Gram-negative, facultative anaerobe bacilli, part of the Enterobacteriaceae family, with an ability to ferment maltose and inability to ferment lactose 1).