UTI Update

By | 2017-01-13T20:43:40+00:00 December 1st, 2009|
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Q. I’ve been managing my bladder with a Foley indwelling catheter. I’m always looking for extra ways or ideas to avoid UTIs, and I heard about a catheter that is coated with some type of antibiotic. Is there such a thing? And if so does it work?

A. Craig, your questions are timely. To answer to your first question, there is a new antibacterial (not antibiotic) infused catheter that recently entered the consumer market.

To help answer your second question we need to look at one of the main ways bacteria get into a bladder that is managed by an indwelling (Foley) catheter and how an antibacterial agent in a catheter can help reduce the chances of this happening.

As soon as an indwelling urinary catheter is put in place, a microscopic film — referred to as biofilm — rapidly starts to form on the catheter. A 2008 study done at Cardiff University in the UK showed significant biofilm growth on catheters after just 18 hours. This layer of biofilm creates a pathway for the bacteria — they march up the biofilm where they take hold in the bladder, multiply and cause a urinary tract infection.

In addition to creating a bacterial pathway to the bladder, the biofilm layer can also cause encrustation, a crystalline buildup that can block the catheter and can stop the flow of urine. An antibacterial indwelling catheter should help in reducing encrustation. However, the Cardiff study observed that simply putting antibacterial material on an indwelling catheter was not enough; to be effective the antibacterial material needs to diffuse into the urine to effectively fight UTI and encrustation.

A PubMed search revealed several recent papers and clinical trials on indwelling catheters infused with antibacterial agents. The studies found that nitrofurazone — a broad-spectrum antibacterial agent — was the most effective antibacterial coating for reducing UTIs. The studies concluded that the use of nitrofurazone-coated indwelling catheters resulted in a significant reduction in the incidence of UTIs.

In August 2009, Rochester Medical introduced a new line of all-silicone (important for people with latex allergies) nitrofurazone-impregnated Foley catheters. The Rochester design impregnates both the inner and outer surfaces of the catheter with nitrofurazone. The catheters are designed to elute a controlled release of nitrufurazone into the urethra and bladder — hence addressing the need to diffuse the antimicrobials into the urine to fight UTI and encrustation. A 2007 study showed that the Rochester Foley continued to elute nitrofurazone at or above bactericidal (high enough to kill bacteria) levels for at least 30 days.

The Foley version of Rochester’s nitrofurazone-impregnated catheter is called the StrataNF, and is the only Foley catheter indicated for the reduction of bacterial catheter-associated UTIs (CAUTI). The company also offers intermittent versions of the nitrofurazone-impregnated catheters called the Magic3 + antibacterial, and Magic3 + antibacterial plus hydrophilic.

The catheters are covered under Medicare. As always, it is a good idea to check with your insurance company in advance.

For online information: www.rocm.com/products.php

Q. I recently had a recurring bladder infection that took three months and many courses of antibiotics to get rid of. While I was trying to get rid of the infections, I asked my doctor if there was anything I could do to help prevent them from returning. He prescribed a medication called Hiprex and said I can’t start Hiprex until after my final course of antibiotics is over.
I finished my final course of antibiotics and went to pick up the Hiprex prescription. When went to pay for it I almost fell out of my chair — a one-month supply was over $70. What is in this stuff and does it work?
— Steve

A. Hiprex is a brand name for the generic compound Methenamine Hippurate. Other brand names include Mandelamine and Urex.

Methenamine hippurate has been used as a prophylaxis treatment to help prevent, or suppress UTIs since the early 1980s. Although some reference materials incorrectly refer to it as an antibiotic, the Physicians Desk Reference says it is an anti-infective drug — specifically an acidifier. It makes the urine very acidic, and bacteria don’t like to live in an acidic environment.

The information on Hiprex — from RXList.com — says that the drug should only be used after a bacterial infection has been completely eradicated by antibiotics. But it doesn’t say why.

Methenamine hippurate usually comes in tablet form and is taken twice a day by mouth with a full glass of water. It is important to stay hydrated while taking it. Side effects listed include stomach upset and it is suggested that it be taken after meals. And as you discovered, it isn’t cheap. Average prices run around $2.35 or more per tablet.

A 2007 study done by Prince of Wales Hospital in New South Wales, Australia, focused on doing an extensive literature search to assess the benefits of methenamine hippurate in preventing UTI. After combing more than 13 studies with 2032 participants, the study’s conclusions were that methenamine hippurate may be effective for preventing UTI in people without renal tract abnormalities (normally working urinary system), but it does not appear to work in people with a neurogenic bladder (bladder effected by SCI).

Also in 2007 the Prince of Wales Hospital Spinal Medicine Department did a study of methenamine hippurate specific to people with spinal cord injuries. The study consisted of a randomized controlled trial of 305 people for a 6-month period. One third of the participants received 1 gram of methenamine hippurate twice a day, one third of the participants received 800 mg of cranberry twice a day and the final third received a placebo. The conclusion of the study was there is no benefit in prevention of UTI with the addition of methenamine hippurate or cranberry tablets to the usual regimen of people with neurogenic bladders following SCI.

Based on these studies, you may want to ask your doctor if there is another option to help prevent recurring UTIs and hang onto the 70 bucks a month. Then again I know plenty of people with SCI that regularly take cranberry tablets to prevent UTI, it works for them and they swear by them. Like a lot of options for bladder health, the bottom line is, does it work for you?