Are mycotoxins risk factors for endemic nephropathy and associated urothelial cancers?

Evidence supporting a role of mycotoxin, in particular ochratoxin A (OA) and citrinin, in the etiology of Balkan endemic nephropathy (BEN) and associated urinary tract tumours (UTT) is reviewed. Both diseases occur in subjects born and/or living in certain rural areas where home-produced and home-stored stable foods were found to be more frequently contaminated by the OA and citrinin. OA levels in blood and urine from patients with BEN or UTT were higher than in controls. OA and possibly other mycotoxins cause endemic porcine nephropathy, a disease with morphology and clinical course similar to those of BEN. OA was carcinogenic in two rodent species with kidney as a major target organ. Animals and strains phenotype as fast metabolizers of debrisoquine were more susceptible to OA-induced carcinogenicity. Among BEN/UTT patients, a greater proportion of fast metabolizers was reported. Although no epidemiological proof of a direct causal role of mycotoxins in BEN/UTT etiology has been presented, the data accumulated so far indicate a need for prospective studies in which mycotoxins as well as other risk factors should be considered.