Clostridium difficile, routinely referred to as “C diff”, is a bacteria that resides in the colon. It can produce toxins that cause fever, abdominal pain, diarrhea – a manifestation of colitis, or inflammation of the colon.
Usually, the infection is caused by the use of antibiotics. It is quite common, with nearly half a million cases and over 29,000 deaths.
From 2003-2006 C Diff infections were noted to be more severe and more refractory than previously noted. A hypervirulent or more aggressive strain was found to be responsible. This strain produces a new toxin not found in the prior strain and increased levels of the usual toxins.
There has been increased sensitivity regarding the normal ecosystem of the bacteria that inhabit our bodies since then, as well as antibiotic avoidance when possible.
Some patient may be carriers of the bacteria, meaning that they carry the bacteria in their colon but have no evidence of illness. The carrier rate in healthy adults is 3 percent, but increases to 20 to 50 percent in adults in hospitals and long-term care facilities.
This bacteria produces spores that resist drying and can remain viable on hard surfaces for some time. Once the environment becomes contaminated, another person can pick it up by touching the spores and then touching their mouth, ultimately unknowingly ingesting the spores.
The most common risk factors for illness include antibiotic use, hospitalization, advanced age, and other severe illness, although other populations are at risk as well. Also the use of medications that reduce stomach acid may increase risk for this problem.
The most important step in treatment is to stop the inciting antibiotic as quickly as possible. Specific treatment that targets C Diff is also used. Avoidance of medications that slow down the motility of the colon, such as Imodium, is important to decrease risk of complications.
Once treated, the patient often will continue to shed the toxin in their stool so repeat testing for cure is not indicated. Approximately 50 percent of patients have positive stool tests for as long as six weeks after completing treatment.
To limit spread to others in health facilities the patient is placed in isolation. Hand hygiene using soap and water maybe important in this regard since alcohol-based hand solutions maybe less effective because the spores are not killed by alcohol hand treatments.
Relapses, a common problem, typically occur one to three weeks after treatment, although relapse can occur up to two months later. Risk factors for relapses include increased age, severe underlying illness, and use of further antibiotics. There are several methods that have been tried to reduce relapses in those that are having recurrent illness.
That includes using alternate antibiotics, using a prolonged course of antibiotic for treatment, and using fecal bacteriotherapy. Probiotics have not shown treatment benefit.
Fecal bacteriotherapy is often referred to as stool transplant. It involves collecting stool from a normal donor, processing the stool, then reimplanting the processed stool into the colon of the patient. This can be done via endoscope from the upper GI tract or placed directly into the colon via colonoscopy. The success rates are over 90% in preventing further relapses. The new bacteria are found in the colon many months later, so the protection persists for a long period of time.
Ideally a vaccine to protect against the disease would be the best protection for initial or recurrent disease. ID Care is a trial site for a candidate vaccine. However, until we prove the vaccine is effective the best protection is avoidance of unnecessary antibiotics in the first place.
Ellen J Hirsh, MD, works at the Hillsborough-based ID Care.