CT scan without contrast, right after the patient had developed fever. (1) Decreased volume of pyelum/hydronephrosis compared to the previous CT scan. (2) Increased area of lower density in the renal parenchyma, suspect for extension of pyelonephritis as tissue becomes increasingly hydrous. (3) Resorption of the blood clot in the proximal ureter. There are no signs of an encapsulated abscess