Abstract: TH-PO170
Fanconi Syndrome in an Elderly Patient with Membranous Nephropathy During Treatment with Immunosuppressant Mizoribine
Session Information
- Drug Events Trainee Case Reports
November 07, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 2102 CKD (Non-Dialysis): Clinical, Outcomes, and Trials
Authors
- Nishikawa, Sho, University of Fukui, Fukui, Japan
- Takahashi, Naoki, University of Fukui, Fukui, Japan
- Nishikawa, Yudai, University of Fukui, Fukui, Japan
- Morita, Sayu, University of Fukui, Fukui, Japan
- Nishimori, Kazuhisa, University of Fukui, Fukui, Japan
- Kobayashi, Mamiko, University of Fukui, Fukui, Japan
- Fukushima, Sachiko, University of Fukui, Fukui, Japan
- Yokoi, Seiji, University of Fukui, Fukui, Japan
- Mikami, Daisuke, University of Fukui, Fukui, Japan
- Kimura, Hideki, University of Fukui, Fukui, Japan
- Kasuno, Kenji, University of Fukui, Fukui, Japan
- Iwano, Masayuki, University of Fukui, Fukui, Japan
Introduction
Acquired Fanconi syndrome (FS) is often caused by drugs (antibacterial drugs, antiviral agents and anticancer agents), is sometimes caused by autoimmune diseases, monoclonal light chain associated diseases and heavy metal poisoning. Mizoribine (MZR) is an oral immunosuppressant inhibiting inosine monophosphate dehydrogenase, widely used in Japan for treatment of autoimmune diseases, nephrotic syndrome and renal transplantation. Recently several studies have shown that a combination of steroids and MZR is effective in patients with membranous nephropathy (MN). Furthermore, there is an interesting report that the addition of steroid after MZR monotherapy for two or three months may be beneficial for patients with MN.
Case Description
An 80-year-old man was referred to our hospital with FS, acute kidney injury (AKI) and severe proteinuria (15 g/gCr). Two months before this admission, he was diagnosed with primary MN by his renal biopsy. He and his wife chose outpatient treatment because of his mild dementia due to ageing. Oral administration of MZR was started prior to prednisolone administration. One month later, serum creatine was rapidly increased from 1.9 to 2.7 mg/dL with nephrotic-range proteinuria. In addition, serum albumin was decreased to 1.1 g/dL, and various abnormalities of laboratory data including glucosuria, hypokalemia, hypophosphatemia and hypouricemia were newly recognized. He had no history of exposure to heavy metals or administration of any other additional drug, including Chinese medicines. Hypokalemia, hypophosphatemia, glucosuria, hypouricemia and severe proteinuria were gradually improved by discontinued administration of MZR, additional oral administration of prednisolone followed by single intravenous injection of rituximab. He was finally diagnosed with MZR-induced FS from this clinical course and his typical laboratory data except proximal tubular acidosis.
Discussion
To the best of our knowledge, this is the first report demonstrating FS induced by MZR. Although the mechanisms induced proximal tubular dysfunction with MZR are unknown, nephrologists should pay attention to the onset of FS during treatment with MZR.