Supplement nephropathy due to long-term, high-dose ingestion of ascorbic acid, calcium lactate, vitamin D and laxatives.
A 48-year-old Japanese woman previously in good health was found to have severe proximal tubular dysfunction with a high serum level of ascorbic acid (57.3 microg/ml, reference range: 1.9 - 15.0 microg/ml). Renal biopsy specimen showed marked tubulointerstitial damage, i.e. tubular atrophy, dilatation of tubular lumen with flattened tubular epithelial cells, vacuolization of proximal and distal tubular epithelial cells, and severe interstitial fibrosis with mild infiltration of mononuclear cells. Calcified lesions, which caused tubular obstruction or stenosis, were also seen in interstitial area adjacent to degenerated proximal tubuli. Hypokalemic nephropathy, probably due to long-term use of laxatives, was clearly shown. However, calcified lesions seemed to be caused by inappropriate excessive daily ingestion of ascorbic acid (6 000 mg/day), calcium lactate, and vitamin D because of the patient's misunderstanding that these supplements could keep her in a good health. This condition may be clinically called "supplement nephropathy".
Ohtake
T
T
Department of Nephrology, and Kidney and Dialysis Center, Shonan Kamakura General Hospital, Yamazaki, Kamakura, Japan. ohtake@shonankamakura.or.jp
Kobayashi
S
S
Negishi
K
K
Moriya
H
H
D001205:Ascorbic Acid / Q000008:administration & dosage / Q000009:adverse effects*; D001706:Biopsy; D017610:Calcium Compounds / Q000008:administration & dosage / Q000009:adverse effects*; D002400:Cathartics / Q000008:administration & dosage / Q000009:adverse effects*; D019587:Dietary Supplements / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007678:Kidney Glomerulus / Q000473:pathology; D007773:Lactates / Q000008:administration & dosage / Q000009:adverse effects*; D008875:Middle Aged; D009395:Nephritis, Interstitial / Q000139:chemically induced* / Q000473:pathology; D013997:Time Factors; D014807:Vitamin D / Q000008:administration & dosage / Q000009:adverse effects*; D014815:Vitamins / Q000008:administration & dosage / Q000009:adverse effects*
D017610:Calcium Compounds; D002400:Cathartics; D007773:Lactates; D014815:Vitamins; D014807:Vitamin D; C110051:calcium lactate; D001205:Ascorbic Acid