HDCN Article Review/Hyperlink

World MJ, Stevens PE, Ashton MA, Rainford DJ

Mesalazine associated interstitial nephritis

Nephrol Dial Transplant (Apr) 11:614-621 1996

Mesalazine (5-aminosalicylic acid, 5-ASA) is effective in the treatment of inflammatory bowel disease. Enteric coated preparations delay the release of the salicylate until the drug enters the terminal ileum or colon. World et al report four patients who developed interstitial nephritis while being treated with 5-ASA. They review 12 previously reported cases. This report indicates that renal impairment may occur in as many as 1 in 100 patients, but that severe renal insufficiency only occurs in less than 1 in 500 patients. They observed that the only reliable indicator of 5-ASA induced toxicity is an increase in the serum creatinine concentration. Recovery of renal function was related to the duration of unrecognized renal injury. Patients who continued taking 5-ASA for longer that 18 months after the onset of toxicity did not recover renal function.

Comment: Mesalazine induced interstitial nephritis is an insidious process. Normal urinalysis and the absence of typical features of drug allergy make the diagnosis of mesalazine induced interstitial nephritis more difficult. Since elevation of the serum creatinine may be the earliest and possibly the only manifestation, it should be measured monthly for the first three months after initiation of treatment with 5-ASA, every three months thereafter for a year, and at least yearly for the duration of treatment. (George R. Aronoff, M.D., University of Louisville, Kentucky)