The Usefulness of the Interpretation of Initial Plain CT Scan in Hospitalized Patients with Acute Pyelonephritis without Obstructive Uropathy

To investigate the association between plain computed tomography (CT) findings and clinical characteristics and to characterize the potential factors affecting the disease outcome in hospitalized patients with acute pyelonephritis (APN) without obstructive uropathy, we reviewed our clinical database retrospectively. Five plain CT scan abnormal kidney findings of perirenal fat stranding, thickening of perirenal fasciae, kidney enlargement, dilation of renal pelvis, and abnormal density of renal parenchyma were elucidated in 70 patients with APN without obstructive uropathy who were hospitalized. The association between CT scan findings and clinical characteristics were analyzed. Logistic regression analysis was performed to characterize the potential factors that affect the period until the patient was afebrile using various clinical factors and five defined CT scan findings. Perirenal fat stranding and dilation of renal pelvis were significantly frequent in females and patients with diabetes mellitus. Serum inflammation markers were significantly deteriorated in patients with perirenal fat stranding, thickening of perirenal fasciae and kidney enlargement compared to patients with normal findings. An age-adjusted Charlson comorbidity index ≥ 5 and low serum albumin values were significantly associated with a prolonged febrile period. In conclusion, although abnormal plain CT scan findings at diagnosis are associated with some clinical characteristics, the patient’s intrinsic factors are more useful for predicting the disease outcome in hospitalized patients with APN without obstructive uropathy