Photo Credit: Jelena Stanojkovic

A study in solid organ transplant recipients shows oral therapy for gram-negative bacteremia may not need to be restricted to immunocompetent individuals.

“There is robust literature in immunocompetent populations that suggests a transition to oral agents to treat uncomplicated gram-negative bacteremia is safe and effective,” E. Zachary Nussbaum, MD, explains. “Some of this literature has also suggested that transition to oral therapy can result in shorter hospital stays, improved patient QOL, and fewer adverse events; such events are often associated with complications related to catheters for administration of IV antibiotics.”

However, data on this transition to oral antibiotics among patients who have had a solid organ transplant is limited, as is an understanding of whether the transition to oral therapy is associated with positive patient outcomes, he continues. Further, all randomized controlled trials that assessed the use of oral antibiotics for gram-negative bloodstream infections excluded highly immunocompromised hosts, Dr. Nussbaum and colleagues noted in Clinical Infectious Diseases.

For the study, the researchers aimed to assess the safety and efficacy of oral antibiotic step-down therapy for uncomplicated gram-negative bloodstream infections in patients who had received a solid-organ transplant. Primary endpoints included mortality, bacteremia recurrence, and restart of IV antibiotic therapy; secondary endpoints included length of stay, C. difficile infection, treatment-associated complications, and tunneled central venous catheter placement.

Oral Therapy Reduces Complications & Length of Stay

The researchers identified 120 bacteremia events from 107 patients in the oral therapy group and 42 events from 40 patients in the IV therapy group. Kidney was the most commonly transplanted organ in both groups.

Dr. Nussbaum and colleagues reported no significant differences in mortality, bacteremia recurrence, or restart of IV antibiotics between groups. The researchers noted no difference in treatment duration between groups.

However, patients in the oral antibiotic group had an average length of stay that was 1.97 days shorter (P=0.005). Further, the odds of developing C. difficile infection and other treatment-associated complications were 8.4 times higher (P=0.015) and 6.4 times higher (P=0.002), respectively, in the IV group.

“Patients in the IV group had higher rates of adverse events, including catheter-associated complications,” Dr. Nussbaum says. “This suggests that the transition to oral therapy may be safer than continued IV therapy.”

Using Oral Therapy in Immunocompromised Patients

The results demonstrate the safety and efficacy of transitioning from IV to oral therapy in a cohort of immunocompromised patients and are the first to assess this topic exclusively in solid organ transplant recipients, according to the researchers. The findings also parallel results from studies of immunocompetent hosts.

“The current study indicates that transitioning to oral therapy for uncomplicated gram-negative bacteremia need not be solely restricted to immunocompetent individuals,” Dr. Nussbaum continues.

As a result, he says clinicians now have reference data to support this practice even in highly immunocompromised hosts, such as solid organ transplant recipients, while noting that prospective, randomized trials would confirm these findings.

Another potential benefit of the transition to oral antibiotics in immunocompromised patients includes earlier discharge from the hospital, with the caveat that safe administration of oral antibiotics outside of the hospital setting is arranged. “This may result in significant cost savings and improved patient QOL,” Dr. Nussbaum says.

He continues that future research should also address some of the current study’s limitations.

“Our study was a retrospective review that was limited by a relatively small sample size, and most patients were kidney transplant recipients with bacteremia originating from a urinary source. Larger, randomized controlled trials are needed to confirm and expand the generalizability of our findings.”

Key Takeaways

• Researchers observed no significant differences in mortality, bacteremia recurrence, or restart of IV antibiotics in patients switched to oral therapy
• Patients treated with oral antibiotics also had shorter length of hospital stay and fewer treatment-related complications
• The findings demonstrate the safety and efficacy of transitioning to oral therapy in immunocompromised patients