Ripretinib-Induced Focal Segmental Glomerulosclerosis in a Patient With Gastrointestinal Stromal Tumor (GIST)

Ripretinib, a multikinase inhibitor, is used to treat refractory forms of advanced gastrointestinal stromal tumors. We describe a case of a 76-year-old male with a history of chronic kidney disease stage 3B/A3 (baseline creatine 2 mg/dL, urine protein/creatinine 3.5 gm/gm), diabetes, and aortic stenosis who presented with a sudden onset of lower extremity edema and weight gain of 20 lbs. Laboratory findings showed acute kidney injury (creatinine 2.5 mg/dL), hypoalbuminemia (albumin 2.4 g/dl), and nephrotic range proteinuria (urine protein/creatinine = 17 gm/gm). Renal biopsy showed focal segmental glomerulosclerosis. Ripretinib was stopped, and he was placed on high-dose steroids. After four months of prednisone, improvement in proteinuria and serum creatinine was seen. The clinical course suggested that podocyte injuries were induced by ripretinib, the disease process was presumptively responded to steroids, and the podocytopathy lasted after discontinuation of the medication.