State of the art: imaging of renal infections

Infections of the urinary tract are common and account for a large number of patient encounters in the ambulatory and emergency department setting. Their severity and presentation varies, and although uncomplicated infections can often be diagnosed and treated based on clinical and laboratory findings alone, diagnostic imaging may be necessary in some cases to guide appropriate medical or surgical therapy. We will briefly describe the indications for imaging known or suspected upper urinary tract infections, and the relative benefits and limitations of the different imaging modalities for a given clinical presentation. This will be followed by a discussion of various types of renal infections with a pictorial review of their imaging appearances and differential diagnoses.