Aristolochic acid nephropathy Aristolochia

Numerous reports from many countries have confirmed that plants from the Aristolochia species are the cause of the nephropathy (12,13), and the toxic agent has been confirmed to be aristolochic acid (14). 

In Japan two cases of Chinese herb nephropathy were associated with chronic use of Aristolochia manchuriensis (Kan-mokutsu) (24). The diagnosis was confirmed by renal biopsy and the toxic constituents were identified as aristolochic acids I, II, and D. 

Aristolochic acid and its salts, originated from a weed, Aristolochia clematitis, have toxic and carcinogenic effects to the kidneys and urothelium [45], respectively. Ivic [46] postulated that this plant may be a cause of Balkan nephropathy, but failed to provide convincing evidence from field surveys. Evidence that A. clematitis played a central role in the etiology of Chinese herb nephropathy [47-49], a condition similar to Balkan nephropathy, initiated a second look at this previously abandoned hypothesis and it gained a lot of weight by recent data on the association between DNA adduct formation derived from AA, mutation pattern and tumour development in BEN [50] (see also chapter 33). 

Possible risk factors for the development of aristolochic acid-induced toxicity remain speculative. Over 1,700 patients were exposed to aristolochic acid in the Belgian weight loss clinic, yet only 100 patients with nephropathy have been identified. Furthermore, why is this type of nephropathy not prevalent in China and other Eastern cultures, where use of Aristolochia species is commonplace Possible explanations may include differences in dose and duration of use, since batch-to-batch variability in the composition of herbs in the weight loss regimen was evident. The concurrent use of other medications may also contribute. Many individuals receiving the herbal regimen... 

Flashimoto K, Fliguchi M, Makino B, Sakakibara I, Kubo M, Komatsu Y, Maruno M, Okada M. Quantitative analysis of aristolochic acids, toxic compounds, contained in some medicinal plants. J Ethnopharmacology 1999 64 185-189. Vanherweghem JL. Aristolochia sp and chronic interstitial nephropathies in Indians. Lancet 1997 349 1399 (letter). 

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