When most of us think of diabetes, urinary tract infection isn’t something that immediately comes to mind. Of course, there are the usual complications, such as heart disease, kidney damage, foot ulcers, and blindness—but increased susceptibility to infections is something that many people miss. For an acquaintance of mine, however, a chronic, treatment resistant, urinary tract infection has come to define her diabetic experience of the last 10 months.
Despite having her blood sugar levels under strict control, my acquaintance went a little overboard last Christmas, enjoying a few too many cookies and chocolates—something all of us have been guilty of at one time or another. Sugar, unfortunately for diabetics, and my acquaintance, thickens the blood and makes it more difficult to supply organs such as the heart, kidneys, and nerves with oxygen. As a result of this little misadventure, she developed very specific type of nerve damage, called neurogenic bladder. Neurogenic bladder, in a nutshell, damages the involuntary nerves that make urination possible and allow the bladder to be emptied.
Heading to the hospital shortly after Boxing Day, unable to properly urinate, her doctors fitted her with a catheter: a small tube that leads directly from the bladder to the outside of the urethra, where a urine collection bag is fitted. After a short stay, the nurse on duty taught her how to self-catheterize with a removable, portable catheter. Despite being safer for diabetics than fixed, in-dwelling catheters, self-catheterization is still a painful procedure that requires local anesthetics for some patients. Fortunately, for my acquaintance, an appointment with the urologist was only a few days away.
About three days into her wait for the urologist, she began to show signs of a urinary tract infection. Her urine had increased amounts of blood and she began to experience severe burning pain, on top of the catheterization. After a few quick tests, her family doctor decided that she was suffering from an infection. She was immediately put on high-dose antibiotics to cover the usual forms of bacteria involved. Soon she was feeling slightly better.
About 10 days later, after seeing the urologist, who put her on medication to relax the muscles in her bladder, the catheter was needed slightly less. For a while, everything seemed to be fine, until she began to experience the familiar, stinging, unresolved pain.
For several months, she was treated with antibiotics—on and off—although the infection never really seemed to go. The bacteria responsible was eventually isolated from her urine and cultured. In the end, it turned out to be a garden-variety form of e. coli. Noting that the e. coli isolated from her urine wasn’t particularly resistant to antibiotics, the doctors involved surmised that the e. coli had attached themselves to her bladder wall and formed a biofilm.
Biofilms are like the organized criminals of cellular biology. A biofilm is a community of bacteria, protected by a complex ‘slime’, which is made up of DNA, proteins, and various sugars. Unlike normal, single free-floating bacteria, this colony-like organization changes how bacteria behave and make them less vulnerable to antibiotics. A recent Japanese study, from 2009, suggests that bacteria within a biofilm are 100 to 1000 times more resistant to antibiotics than normal bacterial cells. One of the worst things about biofilms is their ability to attach and grow on virtually any surface—from prosthetic heart valves to indwelling urinary catheters. Indwelling catheters, which are left inside the body for longer periods, are more susceptible to bacterial contamination, as well—meaning that many critically ill patients are susceptible to infections from this route.
While I wish I could say that my acquaintance’s condition is improving, unfortunately it isn’t. For now, she’s stuck with a chronic, untreatable infection that significantly impacts her quality of life. Her work has suffered to the point that she’s considering applying for permanent disability—at least until a more effective treatment ais made available.
Source: Ito et al. Increased Antibiotic Resistance of E coli In Mature Biofilms. Appl Environ Microbiol 2009 June; 75 (12): 4093-4100