Abstract: TH-PO0211
Bevacizumab-Associated Renal Thrombotic Microangiopathy Without Systemic Features
Session Information
- Onconephrology: Anticancer Therapies, PTLD, Paraneoplastic Diseases, and More
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1700 Onconephrology
Authors
- Laxmidhar, Rosy, BJ Medical College, Ahmedabad, GJ, India
- Laxmidhar, Fehmida, Western Reserve Health Education, Warren, Ohio, United States
- Lakhatariya, Khushboo, Western Reserve Health Education, Warren, Ohio, United States
Introduction
Bevacizumab, a monoclonal antibody targeting vascular endothelial growth factor (VEGF), is widely used in the management of metastatic colorectal cancer. While proteinuria and hypertension are recognized renal adverse effects, thrombotic microangiopathy (TMA) is a rare but potentially severe complication. TMA often presents with microangiopathic hemolytic anemia and thrombocytopenia, but presentations limited to the kidney are less commonly reported. We present a case of bevacizumab-induced, renal-limited TMA without systemic features.
Case Description
A 70-year-old man with stage IIIC colorectal adenocarcinoma underwent surgical resection and achieved remission following FOLFOX chemotherapy. Upon disease recurrence with pulmonary metastases, he was treated with FOLFIRI and bevacizumab. The patient’s metastatic lesions responded to therapy, but he developed rising serum creatinine and new-onset proteinuria. Renal ultrasound showed no obstruction. Kidney biopsy revealed chronic active TMA. Laboratory evaluation excluded primary TMA causes, including ADAMTS13 deficiency and hemolytic-uremic syndrome. Notably, there was no evidence of hemolysis or thrombocytopenia, and complement levels were normal, supporting a diagnosis of non-complement-mediated, renal-limited TMA. Discontinuation of bevacizumab resulted in progressive improvement of renal function.
Discussion
Bevacizumab-associated TMA warrants prompt drug discontinuation due to risk of acute kidney injury and progression to chronic kidney disease. This case is notable for its renal-limited presentation without hematologic abnormalities, underscoring the need to consider drug-induced TMA in patients with unexplained renal dysfunction on anti-VEGF therapy. Early recognition and withdrawal of bevacizumab can reverse renal injury. Some cases with complement-mediated TMA can be reversed or attenuated using eculizumab, possibly reducing time to recovery, with fewer long-term sequelae. Clinicians should maintain vigilance for atypical TMA presentations in oncology patients, as timely intervention can improve outcomes and prevent long-term sequelae.