Enterobacteriaceae bacteraemia-related mortality, recurrence risk similar with oral or IV antibiotic treatment
Adult patients hospitalized with Enterobacteriaceae bacteraemia could benefit from an oral, step-down antibiotic treatment regimen instead of continuing an intravenous (IV) antibiotic regimen, according to a retrospective cohort study.
“[Thirty-day] mortality was not different among hospitalized patients who received oral step-down vs continued parenteral therapy for the treatment of Enterobacteriaceae bloodstream infections. However, patients who were transitioned to oral step-down therapy were discharged from the hospital approximately 2 days earlier than those who continued to receive IV therapy,” said the researchers.
The study included 2,161 adults who had been hospitalized with Enterobacteriaceae bacteraemia* at three centres in the US between 2008 and 2014 (median age 59 years, 54.8 percent male, 49.7 percent Caucasian), of whom 876 received oral step-down therapy (transition from IV to oral therapy within 5 days of initiating bacteraemia treatment) and 1,285 continued IV therapy. Patients on oral step-down therapy were less severely ill at infection onset than those who continued IV therapy (median Pitt score at day 1 of antibiotic therapy, 1 vs 2) and were less likely to receive combination antibiotic therapy for >48 hours (6.2 percent vs 12.0 percent).
A total of 1,478 patients were propensity score-matched, with 739 each in the oral step-down therapy and continued IV therapy arms, respectively. The most common source of bacteraemia was urine (40.2 percent), followed by the gastrointestinal tract (20.1 percent) and central-line associated infections (18.4 percent).
The incidence of all-cause mortality within 30 days in the propensity score-matched cohort was comparable between patients who underwent oral step-down therapy and those who continued IV therapy (13.1 percent vs 13.4 percent, hazard ratio [HR], 1.03, 95 percent confidence interval [CI], 0.82–1.30). [JAMA Intern Med 2019;doi:10.1001/jamainternmed.2018.6226]
Recurrence of bacteraemia with the same organism within 30 days was also comparable between patients who underwent oral step-down therapy and those who continued IV therapy (0.8 percent vs 0.5 percent, HR, 0.82, 95 percent CI, 0.33–2.01). However, patients who received oral step-down therapy had a shorter duration of hospitalization (between day 1 of bacteraemia and hospital discharge) than those who continued IV therapy (median duration of hospitalization, 5 vs 7 days; HR, 0.98, 95 percent CI, 0.97–1.00; p<0.001).
The 30-day mortality risk did not differ regardless of bioavailability of the oral drugs (11.0 percent [high bioavailability] vs 12.3 percent [low bioavailability], HR, 1.05), nor did the risk of bacteraemia recurrence (0.6 percent vs 0), though according to the researchers, the study may not be adequately powered to assess this comparison, or the role of oral step-down therapy in overall bacteraemia risk recurrence.
According to the researchers, oral step-down therapy has a multitude of benefits particularly on patients’ quality of life by reducing hospitalization duration, IV catheter-related discomfort or adverse events, and cost.
“[O]ur findings suggest that oral step-down therapy is not associated with inferior clinical outcomes for patients with Enterobacteriaceae bacteraemia who have received appropriate source control and demonstrated an appropriate clinical response compared with patients who continue to receive IV therapy for the duration of their treatment course,” they said, calling for a clinical trial to establish these findings.