Killing more than 29,000 people each year, infection with Clostridium difficile (C. diff or CDI) is the most common healthcare-associated infection in the US. In a disturbing development, new research reveals recurring cases of the infection are soaring.
C. diff is a bacterium at the heart of the battle regarding overuse of antibiotics. The bacterium is not rare, but it can be deadly in those with an already compromised immune system. In a health care setting, patients and medical personnel can easily transmitC. diff is from contaminated surfaces and hands that have been in contact with fecal material.
According to the CDC, more than half a million people are infected with a CDI each year, and many die within 30 days of diagnosis. Those at high risk are the elderly, those on antibiotics, and individuals with an already compromised immune system.
CDIs are dangerous in healthcare settings around patients who are already taking antibiotics. While antibiotics are lifesaving, they also wipe out healthy gut microbes that might serve up a defense against a CDI. Antibiotics prescribed for an infection kill the bad — and the good — bacteria in your body. If you are exposed to C. diff after taking antibiotics, the millions of good bacteria that would otherwise keep C. diff from overpopulating your gut have been killed, leaving an opening for the infection.
A CDI results in symptoms that include:
- Fever, loss of appetite, and weight loss
- Repetitive watery diarrhea
- Abdominal pain
People with recurring CDIs (called "multiply recurrent CD" or mrCDI), don't just have bad diarrhea. C. diff produces virulent toxins that can cause sores along the intestinal wall. Once entrenched, the infection causes flu-like symptoms, fatigue, dehydration, and bloody feces, and can lead to blood infections and sepsis.
C. diff is a robust bacterium. Even when antibiotics succeed in defeating the infection in one patient, it leaves bacterial spores that are resistant to disinfection on open surfaces and medical equipment, and it can remain to reinfect those patients and other victims.
When antibiotics are ineffective in treating these infections, transplants of fecal microbiota are increasingly a treatment solution for otherwise fatal cases. These transplants involve placing healthy fecal material into the intestine of a patient with C. diff to help the intestinal microbiome recover and regain a healthy balance of bacteria to fight the infection.
In a study published in the Annals of Internal Medicine, researchers at the University of Pennsylvania School of Medicine conducted a retrospective study with a large national health insurance database to understand the rate of annual incidence of mrCDI.
The database, from OptumInsight Clinformatics, covers patients on several health plans in the US. Looking at records from January 2001 through December 2012, researchers developed a protocol to identify patients treated for C. diff.
Multiply recurrent CDI is defined as a case of C. diff that has been treated with a minimum of three courses of antibiotics typically used to treat CDIs, including metronidazole, or oral vancomycin or fidaxomicin. Analysts evaluated if using antibiotics or having a history of illnesses like diabetes, chronic kidney disease, or inflammatory bowel disease, could be risk factors.
Study authors report 38,911,718 patients met the criteria for inclusion in the study. Of those, 45,341 developed CDI during the study period. Using several modes of data analysis, researchers delivered sobering statistics about the occurrence of mrCDI, including.
- The median patient age in the cohort of 38 million was 31 years old, and 49% were female.
- On patients with CDIs, the median length of medical follow-up after the first bout was 1.5 years.
- The geographic region with the highest representation of mrCDI in the US is the South, at about 44% of the relevant patient population. In order, the Midwest, and the West followed, with the lowest regional rate in the Northeast.
- Between 2001 and 2012, CDI increased by 42.7%, while mrCDI increased by 188.88% during the same period. That is closing in on an almost 200% uptick in the number of patients battling the most serious form of CDI. According to study authors, this boosts the odds of developing mrCDI after only one bout of CDI by about eight percent.
- As expected, it was the older patients who developed mrCDI, with a median age of 56. Of the patient population, 50.1% were male, and 49.9% were female. At 58.9%, women were more likely to suffer CDI.
- Medications shown to boost the risk of mrCDI include antibiotics (other than those that are used to treat CDI), proton-pump inhibitors, and corticosteroids.
- Chronic illness shown to increase the risk of mrCDI includes chronic kidney disease but not inflammatory bowel disease or diabetes.
- Nursing home diagnosis was associated with higher risk of mrCDI.
Study authors write: "In the subset of the population with multiple recurrences, treatment with antibiotics is substantially less effective than treatment with fecal microbiota transplant." In noting the significant rise in mrCDI, researchers report the rate of recurrent CDI is and will remain, on the increase across the country.
The study suggests higher numbers of CDI result in more cases of mrCDI. Even factoring in the overuse of antibiotics and proton-pump inhibitors, the authors believe the dramatic upswing in cases could be the result of a change, or emergence, of the strain of bacteria responsible for CDIs. The severity of CDI, not just the case numbers, is also increasing.
In a press release, senior author James D. Lewis, of the Univesity of Pennsylvania said: "An additional driver of this rise in incidence could be the recent emergence of new strains of C. difficile, such as NAP1, which has been shown to be a risk factor for recurrent CDI."
The study highlights the increasing danger and incidence of primary and recurring C. diff. Researchers believe fecal transplants are "highly effective and apparently safe" treatment for C. diff in the short term. As well, researchers note further study is needed to establish the long-term safety of these transplants, along with the development of other antimicrobial treatments to address the challenge of this deadly bacterium.