In 1992 a cohort of women with a rapidly progressive interstitial nephritis was identified in Belgium. The cause of this nephropathy was subsequently traced to the use of Chinese herbal medicines designed to encourage weight loss. The offending herbs were banned. Nevertheless more than 100 cases of the disease had been reported in Belgium by 1998. The herb blamed for most of the cases was Aristolochia fangchi which is rich in aristolochic acid (AA); this compound seemed to be the cause of the disease.
Debelle and colleagues review this disorder in a paper in Kidney International. Their in depth review exhaustively covers the subject. They believe that the disorder is seriously under reported. The disease may be quite widespread in India, China, and other Asian nations. Debelle, et al list many botanicals that are suspected to contain AA. The list is so long that you might be tempted to cancel your trip to the Beijing Olympics. These authors favor the less colorful name for this disorder of aristolochic acid nephropathy (AAN) as opposed to Chinese Herbal Nephropathy.
Balkan endemic nephropathy (BEN) was a disease reported, not surprisingly, in the Balkans about 50 years ago. It closely resembles AAN.
Though its pathogenesis is unknown is may be due to wheat contaminated with seeds of Aristolochia clemaditis and thus may be an earlier incarnation of AAN. AA exposure is also strongly linked to urothelial malignancies. The take away message here is to avoid AA. AA containing herbal medicines are widely available in many countries and can easily be obtained over the internet. Caveat emptor.