Potential role of post-transplant hypogammaglobulinemia in the risk of Clostridium difficile infection after kidney transplantation: a case-control study.

Purpose: To identify reversible risk factors for Clostridium difficile infection (CDI) after kidney transplantation (KT) that could lead to a reduction in its incidence and associated complications.

Methods: We performed a single-center case-control study in which 41 patients undergoing KT between February 2009 and July 2013 who developed a first episode of post-transplant CDI were included as cases. Patients transplanted at the same calendar day (± 2 weeks) as each case with no evidence of CDI and comparable risk exposure period were chosen as controls (2:1 ratio). Serum immunoglobulin and complement levels were systematically measured at baseline and months 1 and 6 after transplantation.

Results: Multivariate regression analysis identified age-adjusted Charlson comorbidity index (odds ratio [OR] per unitary increment 1.31; P value = 0.043), delayed graft function (OR 2.76; P value = 0.039), prior cytomegalovirus (CMV) disease (OR 6.85; P value = 0.011) and prior acute graft rejection (OR 5.92; P value = 0.008) as risk factors for post-transplant CDI. Cases with their first episode of CDI occurring beyond the first month were more likely to have IgG hypogammaglobulinemia (HGG) at month 1 (P value = 0.002), whereas cases with CDI beyond the sixth month were more likely to have HGG of any class at month 6 (P value = 0.003). Poor outcome (graft loss and/or all-cause mortality) was more common among cases (adjusted hazard ratio 5.69; P value = 0.001).

Conclusion: The occurrence of CDI exerts a detrimental effect on graft and patient outcome. Post-transplant HGG was a potentially modifiable risk factor for CDI in KT recipients.