Small spikes shaped like shark fins could reduce the number of urinary tract infections experienced by patients equipped with catheters.
These hollow, flexible tubes, made of plastic, drain urine from the bladder into a bag for hospitalized patients who are bedridden and unable to go to the bathroom. They are also used to check how much urine a patient is passing or to ensure that the bladder does not become too full during surgery.
However, the longer the catheter is in place, the more likely a urinary tract infection will occur.
The new catheters have thousands of barbs, so small that they are barely visible to the naked eye, and they line the inside of the tube; each prong also points backwards (towards the end of the tube coming out of the body).
This creates a sort of obstacle course that makes it virtually impossible for infection-causing bacteria to climb up the inside of the catheter and into the urinary tract or bladder.
Small spikes shaped like shark fins could reduce the number of urinary tract infections suffered by patients equipped with catheters (file photo)
Trapped by the barbs, the bacteria are then eliminated through urine.
Around one in five NHS hospitalized patients require a urinary catheter to be inserted. It is estimated that 90,000 people living in the community also suffer from them.
Many are men with severe benign prostatic hyperplasia, where the prostate enlarges and puts pressure on the urethra, the tube that carries urine out of the body.
This can cause urinary retention: in severe cases, urine backs up into the kidneys, causing long-term damage. To prevent this, a catheter is often left in place for months, until men undergo surgery to reduce the size of the prostate.
A study by scientists at Public Health England, published in 2019, found that there are approximately 50,000 catheter-induced urinary tract infections a year in NHS hospitals. The annual cost to the NHS of treating them is around £200 million.
Once insects enter a catheter, they form a slimy film that grows along the lining until it reaches the urinary tract and bladder, where bacteria thrive in the moist environment.
Catheters are often coated with antibiotics or metals such as silver to kill microbes. However, a growing number of bacteria are developing resistance to antibiotics.
The shark fin tips, developed at the California Institute of Technology in the United States, were created after researchers used an artificial intelligence computer program to determine what type of surface was likely best at stopping the spread of bacteria.
Around one in five NHS hospitalized patients require a urinary catheter to be inserted. It is estimated that 90,000 people living in the community also suffer from them (file photo)
The artificial intelligence software simulated what would happen with different surface textures and identified shark fin-like spikes as the best solution.
The researchers used a 3D printer to build a prototype and tested it with a liquid containing E. coli bacteria, the most common source of infections caused by catheters.
The results, published in the latest issue of Applied Sciences, showed that the accumulation of bacteria on the catheter coating over a 24-hour period was less than 1 percent of what is typically seen in standard catheters without special coatings. Clinical trials will begin soon.
Chris Eden, professor of urology at the Royal Surrey County Hospital, welcomed the findings but cautioned that some infection-causing bacteria move in a catheter slightly differently to the E. coli the researchers tested. He told Good Health: “This is an interesting development, but it may not work for all bacteria that colonize catheters.”
