Kidney Biopsy Findings and Clinical Outcomes of US Veterans with Inflammatory Bowel Disease

Prasanth Ravipati; Scott Reule; Alyssa Bren; Lihong Bu; Byron P Vaughn; Patrick H Nachman

doi:10.1159/000534062

Kidney Biopsy Findings and Clinical Outcomes of US Veterans with Inflammatory Bowel Disease

Glomerular Dis. 2023 Sep 30;3(1):233-240. doi: 10.1159/000534062. eCollection 2023 Jan-Dec.

Authors

Prasanth Ravipati^{1

2}, Scott Reule³, Alyssa Bren⁴, Lihong Bu⁵, Byron P Vaughn⁶, Patrick H Nachman²

Affiliations

¹ Division of Nephrology, Department of Medicine, University of Nebraska Medical Center, Omaha, NE, USA.
² Division of Nephrology and Hypertension, Department of Medicine, University of Minnesota, Minneapolis, MN, USA.
³ Division of Medicine, Minneapolis Veterans Affairs Health Care System, Minneapolis, MN, USA.
⁴ University of Minnesota Medical School, Minneapolis, MN, USA.
⁵ Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
⁶ Division of Gastroenterology and Hepatology, Department of Medicine, University of Minnesota, Minneapolis, MN, USA.

Abstract

Introduction: Patients with inflammatory bowel disease (IBD; ulcerative colitis [UC] and Crohn's disease [CD]) may have unique patterns of kidney injury related to their underlying or coexisting disease or to medications. We present the kidney biopsy findings and clinical outcomes of veterans with UC or CD from the US Department of Veteran's Affairs (VA) health system.

Methods: Histopathologic and clinical data were extracted by retrospective review of the VA electronic health record of patients with IBD and a kidney biopsy between 2000 and 2018. Incident end-stage kidney disease (ESKD) was defined as requirement of kidney replacement therapy. Statistical analyses were performed using SAS.

Results: A total of 140 patients (UC: 91 and CD: 49) underwent kidney biopsy. The three most common diagnoses were IgA nephropathy (17.1%), diabetic nephropathy (14.3%), and acute interstitial nephritis (9.3%). Significant interstitial fibrosis, tubular atrophy, and arteriosclerosis were present in 45% of biopsies. Twenty-six percent of patients with UC and 20% of those with CD progressed to ESKD, with a mean time from kidney biopsy of 3.1 and 1.9 years, respectively. Forty-five percent of patients with UC and 34% of those with CD died, with a mean time from kidney biopsy of 4.3 and 4.6 years, respectively.

Conclusion: Among US veterans with IBD who underwent a kidney biopsy, IgA nephropathy, diabetic nephropathy, and interstitial nephritis were among the most common findings. Additionally, features of advanced kidney disease with rapid clinical progression to ESKD or death were observed. These findings suggest a delay and possibly a low rate of diagnosis.

Keywords: Histopathology; Immunoglobin A nephropathy; Inflammatory bowel disease.

Grants and funding

The authors received no financial support for the research, authorship, and/or publication of this article.