Leukocytoclastic Vasculitis Induced by Immune Checkpoint Inhibition in a Patient With Advanced Renal Cell Carcinoma.

A Mexican woman, aged 60 years, presented with fevers and abdominal pain. She had initially presented to an outside emergency department with weakness, malaise, nausea, vomiting, tachycardia to 110s, and fever to 102 °F. Her medical history was relevant for hypertension, prediabetes, and tobacco use (4-5 cigarettes/day for 12 years). There was no significant family history. Pertinent labs included hemoglobin 8.0 g/dL, white blood cells 13.1 × 109/L, absolute neutrophil count 10.2 × 109/L, creatinine 1.3 mg/dL, calcium 9.2 mg/dL, and lactate dehydrogenase 682 U/L. Initial imaging showed a large 14-cm right renal mass, with tumor in vein in the right renal vein and inferior vena cava, and extensive bilateral pulmonary emboli. A pulmonary thrombectomy was performed, with pathology on the right lung thrombus consistent with metastatic clear cell renal cell carcinoma (RCC), cT4N0M1, categorized as intermediate risk per the International Metastatic RCC Database Consortium.