Recurrent Clostridioides difficile infections in solid organ transplant recipients: the international CALIPSO study

Abstract Objective To evaluate the risk of recurrent Clostridioides difficile infection (CDI) in solid-organ transplant (SOT) recipients. Methods Retrospective multicenter study including SOT recipients with a first CDI episode in the year after transplantation (Jan 2017-June 2020). The primary outcome measure was recurrence, defined as a new CDI≤56 days from the first episode. A competing risk analysis was performed using the sub-distribution hazard model multivariable analysis. Results 191 SOT recipients were included: 101 (52.9%) were kidney, 66 (34.6%) liver, 11 (5.8%) lung, 8 (4.2%) simultaneous pancreas-kidney, 4 (2.1%) heart and 1 (0.5%) pancreas alone recipients. Treatment for the first CDI were: vancomycin (n=114,59.7%), vancomycin+metronidazole (n=39,20.4%), metronidazole (n=26,13.6%), fidaxomicin (n=9,4.7%), 3 patients did not receive any therapy. After the first CDI, 17/191 (8.9%) patients died within 56-day mortality without having a recurrence, while 23/191 (12%) patients had a recurrence. Among patients with recurrent CDI, 56-day mortality rate was 30.4% (7/23 patients). On multivariable analysis, severe CDI (sHR4.01, 95% CI 1.77-9.08, p<.001) and metronidazole monotherapy (sHR 3.65, 95% CI 1.64-8.14, p=.001) were factors independently associated with recurrence. Conclusions Metronidazole monotherapy is associated with increased risk of recurrent CDI in SOT recipients. Therapeutic strategies aimed to reduce the risk of recurrence should be implemented in this setting.