Progressive interstitial renal fibrosis due to Chinese herbs in a patient with calcinosis Raynaud esophageal sclerodactyly telangiectasia (CREST) syndrome.

A 58-year-old woman with calcinosis Raynaud esophageal sclerodactyly telangiectasia (CREST) syndrome presented with slowly progressive renal dysfunction. She was normotensive with normal plasma renin activity and lacking symptoms of vasculitis. Mild proteinuria was of tubular origin, but serological tests and an absence of sicca symptoms excluded the possibility of Sjögren's syndrome. Light microscopic study of renal biopsy showed interstitial fibrosis with ectasia and degeneration of proximal tubule and lymphocyte infiltration. There were no remarkable changes in the glomeruli. Chromatographic analysis of the Chinese herbs regimen that she had been taking for several years demonstrated aristolochic acid. She was diagnosed as Chinese herbs nephropathy. Therapy with oral prednisolone was markedly effective in improving renal function and anemia. To our knowledge, this is the first report of Chinese herbs nephropathy complicating connective tissue disease. It is important to consider the possibility of Chinese herbs nephropathy when patients treated with Chinese herbs develop renal dysfunction.