The Australasian Society of Infectious Diseases has updated its guidelines on C. difficile infection management to reflect major changes in the therapeutic options available since the recommendations were last published back in 2016.
Aimed at both adults and children in Australia and New Zealand, the latest consensus guidance has replaced oral metronidazole with vancomycin for initial C. difficile infection (CDI) treatment and includes roles for fidaxomicin and faecal-microbiota transplant (FMT) in recurrent/refractory infection.
Explaining the changes in a position paper published in the Internal Medicine Journal [link here], the authors said a head-to-head comparative efficacy and placebo-controlled RCT suggested metronidazole was inferior to vancomycin therapy for initial CDI cure, with the evidence graded as moderate certainty.
The team, which included Australian infectious disease physicians and microbiologists, said the previous approach using first-line metronidazole had been based on previous unblinded studies, where no significant differences had been identified.
They said metronidazole could be considered as second-line if access to first-line therapy was not possible in non-severe disease, for example due to cost or stock.
As for fidaxomicin, the authors said the narrow spectrum macrocyclic antibiotic had been shown to be non-inferior to vancomycin in the cure of initial CDI (moderate certainty evidence), with no differences in adverse outcomes.
It also allowed for better preservation of the intestinal microbiome, they added.
However, access and cost remained a barrier as the drug was not PBS-listed.
“Currently, we do not recommend fidaxomicin as first-line therapy for initial CDI due to costs within Australia; our position is contrary to international guidelines which suggest a cost–benefit,” the authors said.
“If accessible, fidaxomicin may be considered in patients with multiple risk factors for recurrence.”
Meanwhile, the authors recommended FMT as the preferred option in second or subsequent recurrences of CDI and rescue FMT for severe refractory disease.
They pointed to studies that suggested FMT provided clinical cure in 67%–82% of recurrent CDI within 10–18 weeks. They said that cases of early recurrence might require repeated FMT, however first-line FMT in severe disease remained unclear.
Regarding general management principles, the authors did not recommend probiotic therapy as a primary prevention or an adjunctive therapy due to a lack of evidence, along with recent reports that it might delay reconstitution of the microbiota.
Prophylaxis with CDI-active agents was also not recommended for patients on concurrent antimicrobial therapies, which followed a consensus decision by the European Society of Clinical Microbiology and Infectious Diseases (ESCMID).