The HU value of renal collecting system in Group 2 was significant higher (P = .02), and analysis showed significant differences between the 2 groups in WBC count (WBCC), neutrophils, serum CRP (P < .001), serum albumin (P = .004), urine leukocyte (P = .029), WBCC (P < .001), urine culture in midstream urine (P < .001), grade of hydronephrosis (P = .02), and thick wall of the renal pelvis (P = .01) (Table 2 and Fig. 1). Here, CRP is linked to hydronephrosis.