Baseline graft status is a critical predictor of kidney graft failure after diarrhoea

Diarrhoea is one of the most frequent complications after kidney transplantation (KT). Non-infectious diarrhoea has been associated with reduced graft survival in kidney transplant recipients. However, the risk factors for renal allograft loss following diarrhoea remain largely unknown.

Between January 2010 and August 2011, 195 consecutive KT recipients who underwent standardized microbiological workups for diarrhoea at a single centre were enrolled in this retrospective study.

An enteric pathogen was readily identified in 91 patients (47%), while extensive microbiological investigations failed to find any pathogen in the other 104. Norovirus was the leading cause of diarrhoea in these patients, accounting for 30% of the total diarrhoea episodes. The baseline characteristics were remarkably similar between non-infectious and infectious diarrhoea patients, with the exception that the non-infectious group had significantly lower graft function before diarrhoea (P = 0.039). Infectious diarrhoea was associated with a longer duration of symptoms (P = 0.001) and higher rates of acute kidney injury (P = 0.029) and hospitalization (P < 0.001) than non-infectious diarrhoea. However, the non-infectious group had lower death-censored graft survival than the infectious group (Gehan-Wilcoxon test, P = 0.038). Multivariate analysis retained three independent predictors of graft failure after diarrhoea: diarrhoea occurring ≥5 years after KT [hazard ratio (HR) 4.82; P < 0.001], re-transplantation (HR 2.38; P = 0.001) and baseline estimated glomerular filtration rate <30 mL/min/1.73 m2 (HR 11.02; P < 0.001).

Our study shows that pre-existing conditions (re-transplantation, chronic graft dysfunction and late occurrence) determine the primary functional long-term consequences of post-transplant diarrhoea.