Breakthrough in fight against infection misery
Scientists at Cardiff University, UK, have made a breakthrough in a 30-year battle to solve a medical problem, which causes pain and misery for millions of people around the world, and costs health services many millions of dollars.
Dr David Stickler, a bacteriologist in the Cardiff School of Biosciences believes he and his team have developed a way of overcoming a common infectious complication, which plagues many patients undergoing long-term bladder catheterisation.
"It is estimated that some 400 million urinary catheters are used world-wide each year, and everyone who is catheterised for a month or more can expect to suffer an infection," explained Dr Stickler.
"About half of these patients will acquire infections with a bacterium called Proteus mirabilis. This organism colonizes the catheter and induces the formation of crystalline material from urine, which builds up on the catheter and eventually blocks the flow of urine from the bladder" he added. "This can lead to the painful distention of the bladder and if the problem is not noticed and dealt with, the retention of urine can result in episodes of kidney or bloodstream infections which can seriously jeopardize the health and well-being of the patient"
"The misery and cost that this problem has caused over the years is incalculable," said Dr Stickler. "The catheter has hardly changed since it was invented in 1937, and infection is inevitable among long-term users.
"Antibiotics are generally ineffective against these infections and currently the only solution is to change the catheter regularly, but the infection always returns."
Having examined this problem since 1970, Dr Stickler and his colleagues believe they have found the answer in the chemical triclosan – commonly found in toothpaste, mouthwash, deodorants and anti-bacterial cleaners such as Microban.
Instead of using sterilised water to inflate the small balloon which holds the catheter in the bladder, they used a mild triclosan solution, and achieved remarkable results.
In laboratory experiments reported in The Lancet they infected artificial bladders with Proteus mirabilis in such quantities that the encrustation blocked the catheter within 24 hours, when the balloon was inflated in the conventional way with water.
However, when they inflated the balloons with the triclosan solution in the infected "bladder", there was no build-up of the catheter blocking material, even after the end of the seven-day trial.
"The triclosan diffuses through the silicone balloon and eliminates the bacteria from the bladder" explained Dr Stickler. "It even impregnates the silicone the entire length of the catheter protecting it from further colonization."
"This is a tremendously exciting breakthrough after many years of work," he said. "At last we could have the solution to these infections which cause immense misery to vast numbers of people, particularly the elderly."
Further research is needed on several fronts, Dr Stickler explained. They must check whether the triclosan adversely affects the balloon, whether there could be bacterial resistance to the triclosan, and how this method works with latex – the other common substance used to make catheters.
Together with colleagues from the Institute of Urology at Southmead Hospital, in Bristol, England, the team is now applying for funding and permission to conduct clinical trials.
Cardiff University | Andrew Weltch