A 45-year-old patient, who had complained about pain in the left lumbar region for 4 days, reported for abdominal ultrasound. So far, the patient had experienced several attacks of renal colic during which he passed two concrements. This time, the pain was different than the previous ones. In the urine sediment up to 4 fresh erythrocytes and 5 leukocytes per high power field were found. In two previous US examinations performed in 2 and 3 year intervals, single concrements of 3–5 mm were observed in the calyces, which was confirmed in the current examination. Moreover, the current examination revealed a bulge in the left kidney on the outer outline of the middle fragment of the cortical layer (fig. 1).
Fig. 1.
What should the examiner think about?
A. renal tumor;
B. renal abscess;
C. dromedary hump;
D. subcortical cyst.