Catheter-Associated Urinary Tract Infections (CAUTIs or just catheter UTI’s) can be extremely virulent bacterial infections which are very difficult to treat and eradicate.
With a 5% cumulative increased risk of bacteriuria per day of a fitted catheter, we can assume that within 1 month of having a catheter a patient has developed some form of a bacterial infection. CAUTIs are the most common cause of gram-negative bacteraemia in hospitalised patients and are responsible for 40% of Hospital-Acquired Infections (HAIs).  Biofilms on the indwelling catheter have been shown to be the main cause of CAUTI and can also be responsible for the blocking of catheters. 
Recurrent UTIs, can lead to the total cost of episodes per annum across the UK to be greater than £1 billion. 
Biofilms on catheters and prostheses are also the prime source of antibiotic resistance in persistent bacterial infections, which make them incredibly challenging to eliminate with antimicrobial agents.  This is because one of the key characteristics of biofilms is the heightened survival to antibiotics and resistance to the immune system of the host; bacteria in biofilms can be up to 1000 times more resistant to antibacterials than bacteria in the planktonic state. Therefore, biofilms provide a survival aid to their residing microorganisms, accounting for the virulent infections which are resistant to antibacterials.
The problem is not only patient stress
The financial burden of catheter UTI’s on the NHS is staggering, with the cost of just one episode at £1,968, in the National Evidence Based Guidelines provided by NICE.  Within 2-10 days, 30% of catheterised patients will develop bacteriuria, with 24% of them progressing to develop CAUTI symptoms. CAUTI bacteraemia is responsible for a 13-33% mortality rate so it’s incredibly important the infections don’t reach this stage. The cost of one catheter UTI episode gives an approximate blended cost of £4,600 per annum for patients with recurrent UTIs, although this value can be much higher, leading the total cost of episodes per annum across the UK to be greater than £1 billion.  CAUTIs are incredibly costly, for example extending the length of hospital stay by 6 days, with around 43-56% of all UTIs being associated with indwelling catheters. This further demonstrates the importance of finding a solution, especially with the financial burden to the NHS of £150 million from HIAs.
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