New C diff Risk Factors Revealed in Mexico

Rifampin treatment is a new risk factor for recurrent Clostridium difficile (C diff) infection episodes in patients aged 51-60 years, according to a paper published in Biomedical Journal.

Investigators from Mexico assessed C diff infection risk factors among patients in different age groups in order to determine the risk factors for both severe-complicated and recurrent C diff infections. The investigators identified patients using PCR testing, in addition to evaluating the patients for clinical, demographic, epidemiological, and microbiological risk factors for C diff.

Known C diff risk factors included advanced age, use of broad-spectrum antibiotics, extended hospital stays, stay at the ICU, infection with HIV, cancer, leukemia, lymphoma, autoimmune disorders, pulmonary infections, gastrointestinal procedures, arterial hypertensions, and the use of immunosuppressive drugs, antacids, and steroids. However, they aimed to uncover move C diff risk factors including in non-elderly groups.

During the study period, the study authors identified 805 patients who had nosocomial diarrhea, of whom 248 patients were confirmed to have C diff infections. About two-thirds of the patients were male and 75% were less than 60 years old. About 20% were young adults, between 21-30 years old, and approximately another 20% were mature adults, aged 51- 60 years.

Most of the patients had the common symptoms associated with C diff infection, including hypoalbuminemia, abdominal pain, abdominal distension, and mucus in stool. Frequently observed comorbidities that included arterial hypertension, kidney disease, and diabetes.

The researchers followed 127 patients with a hypervirulent strain for an additional 8 weeks. Of that group, 22 patients developed at least 1 recurrent episode; 10 of the 22 recurrent episodes were caused by the hypervirulent strain. The remaining recurrent episodes were caused by other C diff strains.

Additionally, the study authors found that 222 patients had been housed in the general ward, and of those, 124 had been hospitalized during the prior 12 weeks before C diff infections. Upon diagnosis, 20 patients were admitted to the ICU. The investigators also noted that two-thirds of the patients had previously undergone antibiotic treatment, most commonly with clindamycin, cephalosporins, metronidazole, and vancomycin.

Female gender and lymphoma were independent risk factors for severe C diff infection. Additionally, mature adulthood (51-60 years), rifampin consumption, and neoplasm were independent risk factors for recurrent C diff episodes.

The study authors also examined the risk factors for 30-day mortality rates, which included autoimmune disorders, leukemia, lymphoma, and previous colistin treatment.

“This Mexican study identified mature adulthood (51–60 years) as an independent risk factor for the development of recurrent C diff infection,” the study authors wrote. “The different conclusions with respect to the most vulnerable age group may be explained by the fact that most C diff infection surveillance studies have focused primarily on the elderly, excluding younger adults and children.”

The study was especially successful at identifying this novel and at-risk population as it caters mainly to traumatized younger patients.

“We are the first to report that rifampin and colistin are independent risk factors for recurrent C diff infection and 30-day mortality, respectively,” the study authors said, while adding that the drug was not used until recently because of its nephrotoxicity. “It should be noted, though, that only seven patients received colistin therapy before the C diff infection diagnosis. This risk factor is significant because recent studies have reported infections due to multidrug-resistant strains that were only susceptible to colistin.”