Continuous Enteral Vancomycin Effective Treating Severe C Difficile Infections

Haley Peters, PharmD

After failing first-line treatment, continuous enteral vancomycin (CEV) might be a suitable option treating patients with severe clostridium difficile infections (CDI).

A team, led by Haley Peters, PharmD, Critical Care Pharmacy, Indiana University Health, investigated whether continuous enteral vancomycin (CEV) infusion through a postpyloric feeding tube could be a less invasive, efficacious, and safety option to treat high surgical risk patients.

The Problem

Severe C difficile infection-related colitis comes with high morbidity and mortality rates, with a high-degree of suspicion of infection required for susceptible patient population for early diagnosis and treatment.

Currently, guidelines call for first-line treatment of oral vancomycin with intravenous metronidazole. In addition, when the medication fails, an early total colectomy is conducted.

For critically ill patients with a high surgical risk and multiple comorbidities, loop ileostomy creation and enteral vancomycin infusion have been used with limited success.

The Study

In the study, the investigators examined 11 non-pregnant patients admitted to the intensive care unit (ICU) for severe CDI between October 2012 and October 2016. Each patient received continuous enteral vancomycin following the failure of conventional therapy at Methodist Hospital. The median age of the patient population was 64 years and 67% were females.

Several patients had comorbidities, including diabetes (n = 3), hypertension (n = 6), coronary artery disease (n = 2), cerebrovascular accident (n = 1), acute kidney injury or end-stage renal disease (n = 6), and malignancy (n = 1).

For the initial treatment regimen, 10 patients were treated with oral vancomycin with a minimum dose of 125 mg and a maximum dose of 500 mg for an average duration of 101 hours.

Safety

There were some adverse events identified during the initial vancomycin oral treatment.

For example, 4 (45%) patients developed lactic acidosis, 9 (81%), experienced shock, 1 (9%) had toxic megacolon, 3 (27%) had ileus, while 2 (18%) patients were not candidates for surgery.

The 1-2 mg/ml vancomycin was run continuously through a feeding pump at 42 ml/hour through a post-pyloric feeding tube.

The investigators sought a primary efficacy endpoint of clinical improvement defined as a decrease in stool output, decreased vasopressor requirement, or improved leukocytosis.

They also sought secondary endpoints of treatment failure defined as the need for total colectomy or death because of severe CDI.

Clinical Improvement

Overall, clinical improvement was found in 63% (n = 7) of the patients, while treatment failure documented as the need for a total colectomy occurred in 18% (n = 2) of the patients. In addition, death occurred in 27% (n = 3) of the patients.

“CEV resulted in clinical improvement in most patients with severe CDI who were at high surgical risk,” the authors wrote. “Sustained intestinal vancomycin delivery may increase luminal concentration and bactericidal effect. The use of a feeding tube and pump provides an effective and less invasive route of vancomycin delivery in critically ill patients.”

The study, “Outcomes of Continuous Enteral Vancomycin Infusion in Intensive Care Unit Patients: A Novel Treatment Modality for Severe Clostridium Difficile Colitis,” was published online in Cureus.