Thrombotic microangiopathy (TMA) is a rare but serious side effect of tyrosine kinase inhibitor (TKI) therapy. Previous case reports of renal TMA have usually occurred in the first few months of TKI initiation with only very few cases occurring within 2-3 years. We report a case of a patient who was referred to the Nephrology service for nephrotic syndrome and worsening renal function after 8 years of sunitinib therapy for metastatic clear cell carcinoma of the kidney. Renal biopsy showed chronic TMA without another secondary aetiology identified. With discontinuation of sunitinib and pharmacological optimisation of his hypertension, his renal function and proteinuria both significantly improved. No relapse or recurrence of disease activity was noted after a year of follow-up. This case highlights the importance of remaining vigilant for the development of renal TMA even after an extended duration of TKI therapy.
BMJ case reports. 2024 Jan 05*** epublish ***
Anukul Ghimire, Rebecca Brassington, Kim Solez, Aminu Bello
Medicine, University of Calgary, Calgary, Alberta, Canada ., Pathology, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada., Nephrology and Immunology, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada.