Allopurinol-Associated Renal Necrotizing Vasculitis
- AKI: Mechanisms - Case Reports
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
- Appelbaum, Zachary, Penn Medicine, Philadelphia, Pennsylvania, United States
- Geara, Abdallah Sassine, Penn Medicine, Philadelphia, Pennsylvania, United States
- Huan, Yonghong, Penn Medicine, Philadelphia, Pennsylvania, United States
- Palmer, Matthew, Penn Medicine, Philadelphia, Pennsylvania, United States
Allopurinol is a xanthine oxidase inhibitor frequently used in the treatment of gout, a common comorbidity in patients with chronic kidney disease (CKD). Post-marketing studies of allopurinol reported a higher incidence of acute kidney injury (AKI) with acute interstitial nephritis representing the most reported histologic finding. We report a case of allopurinol-associated renal vasculitis in a patient with diabetic kidney disease (DKD).
A 68-year-old African American female with a history of DKD, hypertension, and gout was referred to the Emergency Room for nausea and AKI. Her baseline serum creatinine (sCr) was approximately 2.6 mg/dL and increased to 4.02 mg/dL on presentation. Two months prior to presentation, the patient was initiated on allopurinol therapy for gouty arthritis. Other notable findings were elevated liver enzymes and a diffuse purpuric rash. Serologic work-up revealed negative for ANCA, normal complement levels, and negative viral serologies. Because the AKI did not improve with hydration and cessation of allopurinol, a kidney biopsy was performed. The biopsy showed focal vasculitis with fibrinoid necrosis superimposed on a background of diabetic nephropathy with severe interstitial fibrosis and hypertension related arterial sclerosis. Review of the immunofluorescence did not reveal any staining for immunoglobulins, complement, or light chains. This biopsy was most consistent with necrotizing vasculitis. A prednisone taper was initiated for presumed allopurinol induced necrotizing vasculitis. The patient had improvement of kidney function and was subsequently discharged without requiring kidney replacement therapy.
Rash is a known adverse effect of allopurinol therapy, and the majority of these cutaneous reactions improve with discontinuation of allopurinol therapy. The risk of severe adverse reactions is increased in patient of African, Korean, Chinese or Thai ancestry due to the high incidence of individuals who carry the HLA-B*5801 variant allele. Allopurinol-associated renal necrotizing vasculitis is likely a presentation of this type of severe hypersensitivity reaction. Upon initiation of allopurinol, especially the patients at high risk of cutaneous reactions should be counseled regarding this risk and instructed to promptly discontinue the medication and inform the treating provider if a rash is present.