Abstract: PO1484
Cryoglobulinemic Vasculitis in a Patient with Known Thrombotic Microangiopathy
Session Information
- Glomerular Diseases: The Excitement of Clinical Cases
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Gadi, Sanjay, Harvard Medical School, Boston, Massachusetts, United States
- Rhee, Eugene P., Massachusetts General Hospital, Boston, Massachusetts, United States
- Klepeis, Veronica E., Massachusetts General Hospital, Boston, Massachusetts, United States
- Wongboonsin, Janewit, Brigham and Women's Hospital, Boston, United States
Introduction
Acute kidney injury (AKI) is a ubiquitous presentation, but thrombotic microangiopathy (TMA) and cryoglobulinemia are uncommon causes that are not easily diagnosed. We highlight a case of AKI that was found to be cryoglobulinemic vasculitis, an unexpected diagnosis in a patient with history of TMA.
Case Description
A 68-year-old female was diagnosed with giant cell arteritis, with temporal artery biopsy showing inflammation of the adventitia consistent with small vessel vasculitis. She received prednisone and tocilizumab. 6 months later, she was admitted for hypertensive crisis with thrombocytopenia and schistocytes, with creatinine (Cr) elevation to 3.5 from baseline of 1.0. Renal biopsy showed TMA. Tocilizumab was discontinued. She was transitioned to eculizumab, eventually resulting in renal recovery (Cr 1.5) after 1.5 months. However, she continued to feel poorly and returned to the hospital, where she was found to have Cr 4.0.
Physical exam was significant for hypertension and tender retiform purpura. Urine studies were consistent with cellular casts. Dermal biopsy showed dermal necrosis but no intravascular thrombi. Renal biopsy ultimately revealed cryoglobulin deposition, resulting in a diagnosis of cryoglobulinemic vasculitis. She was treated with prednisone, rituximab, and cyclophosphamide with good renal response, and discharged with Cr 2.4.
Discussion
The finding of cryoglobulin on this patient’s renal biopsy was subtle, causing a near-miss in her diagnosis. Her history and repeat clinical evidence of TMA further confounded her presentation. Therefore, when TMA is on the differential, workup should also evaluate for cryoglobulinemia. Her prior diagnosis of GCA also acted as a confounder, though absence of panarteritis and large vessel involvement on temporal artery biopsy may have hinted at underlying systemic vasculitis.
While eculizumab is a standard therapy for TMA, there is limited evidence for its use in treating cryoglobulinemic vasculitis. This patient’s positive renal response to eculizumab supports the potential role of complement inhibitors in treating cryoglobulinemia. It remains possible that the patient could have had TMA and cryoglobulinemia concurrently, with renal biopsy during this presentation only capturing the latter. Therefore, further research into the role of complement inhibitors for cryoglobulinemia is needed.