Background: An 18-year-old previously normotensive man was referred to a hypertension unit with blood pressure readings of 140-150/100-110 mmHg. Renal ultrasound had shown a right renal subcapsular fluid collection and an abdominal computed tomography scan had revealed a large cystic lesion surrounding the right kidney with a thick wall and irregular peripheral calcification consistent with a long-standing traumatic perinephric hematoma.
Investigations: Physical examination, renal artery duplex ultrasonography, magnetic resonance imaging of the abdomen, isotopic renography with technetium-99m diethylenetriamine pentaacetic acid, and a renal venous renin ratio study.
Diagnosis: Hyperreninemic hypertension as a result of presumed abdominal trauma.
Management: Removal of the affected kidney.