Abstract
INTRODUCTION: Page kidney causes secondary hypertension due to external compression of the renal parenchyma and renal hypoperfusion. CASE PRESENTATION: A 21-year-old healthy man was diagnosed with hypertension during a medical examination 3 months after he had gotten a bruise at the right lumbar region. The patient's blood pressure was 176/120 mmHg. Computed tomography showed a large encapsulated cystic lesion around the right kidney and severe external compression of the renal parenchyma. Dimercaptosuccinic acid renal scintigraphy revealed decreased right split renal function. Therefore, the patient was diagnosed with a Page kidney. Percutaneous drainage of the hematoma was performed. However, the hematoma enlarged again. Capsulectomy was subsequently performed. The pathological findings revealed capsule fibrosis and hyperplasia of the capillaries in the inner capsule layer. After capsulectomy, the patient's blood pressure normalized. CONCLUSION: Blood leakage from the fibrotic capsule likely maintained the hematoma. Capsulectomy is recommended in cases involving an encapsulated perineal hematoma.