Abstract: FR-PO032

Recurrent Acute Interstitial Nephritis Secondary to Crohn’s Disease

Session Information

Category: Nephrology Education

  • 1302 Fellows and Residents Case Reports

Authors

  • Abdelwahab, Dina, Mayo Clinic, Scottsdale, Arizona, United States
  • Keddis, Mira T., Mayo Clinic, Scottsdale, Arizona, United States
Background

Immune mediated tubulointerstitial nephritis secondary to Crohn’s disease is uncommon. We report a case of recurrent episodes of acute kidney injury (AKI) due to acute interstitial nephritis (AIN) coinciding with Crohn’s flare-up in an otherwise healthy man

Methods

A 37 year old male with 7 year history of Crohn’s disease was found to have an increased creatinine to 1.7 mg/dL from a normal baseline of 1.3 mg/dL. He was treated with mesalamine for 18 months prior to the increase in creatinine. Kidney biopsy showed acute eosinophilic interstitial nephritis suspicious for mesalamine associated AIN. Mesalamine was discontinued and he was treated with a 6 months course of tapering dose of prednisone. His creatinine peaked as high as 2.2 mg/dl and ranged between 1.7-1.9 mg/dl during treatment. 4 months after discontinuation of prednisone, he developed a flare up of his Crohn’s disease with diarrhea and hematochezia. Laboratory results showed an increase in creatinine to 2.4 mg/dl in absence of any medications. Urinalysis was performed and showed 1-3 white blood cells. Repeat kidney biopsy was performed and showed acute on chronic tubulointerstitial nephritis with eosinophils with moderate background fibrosis and tubular atrophy. The findings of acute on chronic interstitial nephritis in the context of active Crohn’s flare and absence of nephrotoxic medications confirmed suspicion for Crohn’s associated AIN. He was treated with prednisone for 8 weeks and started on adalimumab for treatment of his Crohn’s disease.

Conclusion

This case highlights the uncommon presentation of AIN as a primary extra-intestinal complication of Crohn’s disease. We hypothesize that treatment of Crohn’s disease will improve renal outcome.