Epidemiology of Campylobacter spp. infection in kidney transplant recipients: a retrospective multicentric case-control study in France

Background Campylobacteriosis in kidney transplant recipients (KTR) is the most common identified bacterial cause of diarrhoea. Risk factors in KTR are unknown. Methods A 10-year multicentric, retrospective 1:1 case control study was performed in France between 2010 and 2020. The main aim was to identify factors associated with Campylobacter-related infection in KTR. The KTR with a functional graft and campylobacteriosis (positive stool culture and/or blood culture and/or positive nucleic amplification test) and their control matched on transplantation date within the same center were included. Results We identified 326 patients with campylobacteriosis. The estimated incidence-rate of campylobacteriosis was 2.3/1000 patients-years. The infection occurred at a median of 2.4 years post-transplantation. The independent risk factors for campylobacteriosis were (i) use of corticosteroids as maintenance regimen (75.8 vs 66%; p < 0.001), (ii) acute rejection (8.9 vs 4%; p = 0.048), (iii) low lymphocyte count (0.96 vs 1.4 G/L; p < 0.001) and (iv) low basal eGFR (44.2 mL/min/1.73m2 vs 57.5 mL/min/1.73m2; p<0.001). Fluoroquinolone was initiated in 64 (21.4%) patients, with 51.1% of antimicrobial resistance, whereas almost all strains were erythromycin sensitive. Conclusion Campylobacteriosis has a higher incidence in the two first years of transplantation. The factors independently associated with campylobacteriosis are corticosteroids as maintenance immunosuppressive regimen, low lymphocyte counts, low eGFR and a history of acute rejection. Due to high antimicrobial resistance with fluoroquinolone, the first line of treatment should be azythromycin.