The sonographic appearance of acute pyelonephritis.Ultrasound is insensitive to the changes of acute pyelonephritis, with most patients having 'normal' scan, and abnormalities only identified in ~25% of cases . Possible features include: •particulate matter in the collecting system •gas bubbles (emphysematous pyelonephritis) •abnormal echogenicity of the renal parenchyma ◦ •focal/segmental hypoechoic regions •mass like change •loss of corticomedullary differentiation, decreased visualization of renal sinus fatUltrasound is however useful in assessing for local complications such as hydronephrosis, renal abscess formation, renal infarction, perinephric collections, and thus guiding management.
