Patent Application
20220370688
The present disclosure generally relates to urinary catheters and methods for preventing bacterial infections, and more particularly, to catheters and methods for preventing urinary tract infections. The present disclosure also relates to urinary catheters and methods that inhibit the motility and swarming of bacteria within the urethra.
It is desirable for urinary catheters to have a lubricated or lubricious outer surface to increase comfort of the patient during insertion into and/or removal from the body. One method for rendering the surface of a urinary catheter lubricious is to coat at least the insertable portion of the catheter with a lubricious hydrophilic coating. Another method is to apply a lubricant to the urinary catheter. Lubricity of the catheter minimizes soft tissue damage and reduces overall discomfort during use of the medical device.
Although catheters are typically prepared in sterile environments and are provided with safe handling instructions, catheter users are at risk of contracting a urinary tract infection due to several different factors. For example, the catheter may become contaminated during use and introduce bacteria into the urethra. The catheter also may carrier bacteria along the urinary tract. Additionally, because urine is voided from the bladder through the catheter, urine does not flow directly through the urethra. Thus, urine is no longer a factor in flushing out the urethra or wetting of the urethral tissue.
Therefore, there is a need for catheters, which reduce the risk of urinary tract infections.
There are several aspects of the present subject matter, which may be embodied separately or together in the devices and systems described and claimed below. These aspects may be employed alone or in combination with other aspects of the subject matter described herein, and the description of these aspects together is not intended to preclude the use of these aspects separately or the claiming of such aspects separately or in different combinations as set forth in the claims appended hereto.
In one aspect, a urinary catheter product for insertion into the urethra. The catheter product includes a catheter, and a compound that impedes the mobility and/or swarming of bacteria.
The embodiments disclosed herein are for the purpose of providing a description of the present subject matter, and it is understood that the subject matter may be embodied in various other forms and combinations not shown in detail. Therefore, specific embodiments and features disclosed herein are not to be interpreted as limiting the subject matter as defined in the accompanying claims.
For catheter users, whether in-dwelling or intermittent, urine is no longer a factor that participates in regular flushing or wetting of the urethra. Because the users are unable to void directly through the urethra, the urethra no longer experiences the continuous flushing and re-wetting of the tissues that normally occurs during active voluntary urination. When the mechanism fails, the risk of urinary tract infections increases.
Urinary tract infections can be a result of bacteria swarming and/or traveling up through the urethra towards the bladder. Traveling of bacteria up the urethra is typically not a concern for those who can perform voluntary urination, because normal voiding tends to wash out and eliminate the bacteria from urethra, thereby prohibiting it from traveling toward the bladder and causing infection.
There are certain species of bacteria that are considered good “swimmers,” which swarm and move when they receive certain signals from the surrounding environment. These bacteria are capable of movement even on solid surfaces through excretion of their own extracellular fluids. These motile bacteria also are known to become more pathogenic and increase their motility organelles, such as flagella (a process called hyperflagellation), when sensing certain signals, such as decreased viscosity in the fluids and mucus in their surrounding environment and/or an increase in chemotactants.
In a non-voiding patient, the urethral environment will be fairly viscous, due to the presence of mucosal secretions. When a hydrophilic catheter or a catheter lubricated with a water-based gel is introduced into the urethra, such introduction will likely deposit additional moisture, diluting the secretions, thus decreasing the overall viscosity of the urethral mucus and the surrounding urethral environment. This decrease in the urethral mucus viscosity provides a signal that activates the motility of the bacteria.
Furthermore, when a catheter is inserted into the urethra, the catheter, hydrophilic coating, hydration medium and/or lubricants may include a chemotactant that promotes chemotaxis (the movement of the bacteria in response to a chemical stimulant). For example, the hydrophilic coating and hydration medium may include a chemotactant, such as a polyol or polysaccharide, which stimulates the bacteria to move toward the chemotactant. If the catheter distributes this chemotactant at or near the bladder, the bacteria may be stimulated to undesirably swarm and move toward the bladder.
The catheter products disclosed herein impede bacteria mobility and/or mitigate the risk of bacteria swarming and traveling proximally up the urethra toward the bladder. The catheter products include a compound that physically and/or chemically impedes bacterial movement and/or provides a physical and/or chemical barrier to bacterial movement. Thus, when bacteria are stimulated to swarm and move by signals from changes in the urethral environment, the compounds will physically and/or chemically impede the movement and/or swarming of the bacteria. The compounds that impede the movement and/or swarming of the bacteria may be delivered into the urethra by the catheter.
The compound that physically and/or chemically impedes the movement and/or swarming of the bacteria may be included in any component of a catheter product. For example, referring to
Referring to
In one embodiment, the mobility and/or swarming impeding compound can be incorporated into the catheter, hydration medium or in the hydrophilic coating of the catheter. The compound also may be incorporated into a lubricant that lubricates the catheter.
Such compounds could include positively charged polysaccharides that may physically and electrostatically entrap bacteria, thereby preventing movement and/or swarming. In one example, the compound may be a polysaccharide, such as chitosan, that has a molecular weight between about 10 k MW and 100 k MW. Optionally, the polysaccharide also may have an 80% or greater degree of deacetylation. Additionally, the compounds are deposited in the urethra and may remain therein over a period of time. Furthermore, in intermittent catheterization, wherein catheterization is preformed several times a day, the compound may be redeposited or replenished several times a day with each catheterization procedure. Because the compounds may be in the urethra over a long period of time, the compounds can offer long-term antimicrobial properties, actively killing pathogenic bacteria over longer time scales.
In one embodiment, the compound may be chitosan, wherein the chitosan is incorporated into a hydration medium (such as water) for hydrating a hydrophilic coating of the catheter. Chitosan also may be incorporated into a lubricant for lubricating a catheter. The chitosan may form a hydrogel that creates a barrier to bacteria motility and swarming. The hydrogel is located on the surface of the catheter and is deposited along the urethra as the catheter is inserted into and withdrawn from the urethra. When deposited in the urethra, the hydrogel may physically entrap bacteria and/or entrap the bacteria by positive and negative charge interactions. For example, chitosan is positively charged at physiological and acidic pH, whereas certain bacteria outer surfaces are negatively charged. Thus, the bacteria is attracted to the chitosan and electrostatically entrapped by the chitosan. Furthermore, residual chitosan remaining in the urethra also may function to actively killing bacteria over longer time scales.
When it is desired to entrap bacteria with a positively charged surface, a negatively charged polysaccharide may be incorporated into the catheter product to provide a barrier to mobility that physically and/or electrostatically entraps positively charged bacteria.
When it is desired to inhibit motility of bacteria with a negatively charged surface, a negatively charged polysaccharide may be incorporated into the catheter product to impede motility through electrostatic repulsion.
In another embodiment, the hydration medium or a lubricant may include hyaluronic acid. The hyaluronic acid could be at a concentration of about 1 wt % of the hydration medium or lubricant. As hyaluronic acid is deposited within the urethra, it remains as a physical hydrogel and physically entraps, thereby preventing the bacteria from swarming and/or moving.
In one embodiment, the residual active compounds left behind in the urethra, such as the polysaccharides, will have longer time scales available to enact direct antimicrobial properties, such as killing of the microbes.
It will be understood that the embodiments described above are illustrative of some of the applications of the principles of the present subject matter. Numerous modifications may be made by those skilled in the art without departing from the spirit and scope of the claimed subject matter, including those combinations of features that are individually disclosed or claimed herein. For these reasons, the scope hereof is not limited to the above description but is as set forth in the following claims, and it is understood that claims may be directed to the features hereof, including as combinations of features that are individually disclosed or claimed herein.
The present application claims the benefit of and prior to U.S. Patent Application No. 62/926,900, filed Oct. 28, 2019, which is hereby incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2020/057514 | 10/27/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62926900 | Oct 2019 | US |
