B DOUCET1,2, E NOBLE1, N GRAY1,2
1Department of Nephrology, Sunshine Coast University Hospital, Birtinya, Australia, 2School of Medicine, University of Queensland, Brisbane, Australia
Background: Vitamin C (ascorbic acid) is commonly prescribed for complementary and alternative medical indications or used as a personal health choice. Intravenous vitamin C treatments are gaining popularity in the alternative management of malignant conditions despite the lack of evidence to suggest benefit. The risks of high dose vitamin C may not be appreciated by prescriber or recipient. One of the most devastating adverse effects of high dose vitamin C is oxalate nephropathy.
Case Report: We report two cases of vitamin C induced oxalate nephropathy. A 67 year old male with metastatic oesophageal cancer underwent high dose intravenous vitamin C treatment through a registered Australian medical practitioner for treatment of malignancy. He presented to hospital with anuric renal failure requiring urgent haemodialysis. Serological and imaging investigations revealed no cause of renal impairment. He did not respond to fluid resuscitation and remains dialysis dependant. An 80 year old female presented to hospital with malaise. Investigations revealed severe kidney injury on the background of consuming multiple self-initiated alternative medications, several containing vitamin C. No other cause of renal impairment was identified and vitamin C supplements were ceased. Renal function has improved close to baseline over a one month period. Renal biopsy in both cases revealed severe tubular injury and extensive tubular oxalate crystal deposition consistent with oxalate nephropathy.
Conclusions: High dose vitamin C can cause severe and potentially irreversible renal impairment due to oxalate nephropathy and awareness needs to be raised in conventional and alternative medical communities as well as the general population of the danger associated with this treatment.
Brian Doucet is a second year Nephrology advanced trainee from Queensland. He has previously presented at the ANZSN ASM in 2014 and 2017.