Cross-Sectional Imaging of Renal Cyst Infection

Abstract

Renal cyst infection (RCI) is not uncommon in patients with inherited or acquired multicystic renal disorders and occasionally complicates large or multiple sporadic cysts, particularly during bacteraemia. A potentially severe clinical situation, RCI may either manifest acutely as severe urinary infection or represent an unexpected imaging finding. Without percutaneous aspiration, RCI diagnosis is challenging and relies on consistent clinical, laboratory and imaging findings. This chapter presents the role of CT and MRI and the cross-sectional imaging appearances of superinfected renal cysts. The imaging hallmark of RCI is increased size or changed mural or intraluminal features of a previously known simple cyst. Furthermore, clinical and imaging differentiation of renal abscesses from cystic haemorrhage and necrotic or cystic tumours is discussed.