(Objective) The etiology of acute epididymitis in children remains poorly understood. Several studies have demonstrated that urine tests are negative in the majority of children with acute epididymitis, and the condition is self-limiting. The need for radiological evaluation of the urinary tract in children with acute epididymitis is still debatable. The aim of this study was to describe clinical and imaging findings in children with acute epididymitis. (Methods) We identified 47 children with acute epididymitis at our institute between 2017 and 2021.We retrospectively reviewed their clinical features and radiological and laboratory data. All children underwent ultrasonography of the kidney and urinary tract. (Results) Median patient age was 9 years (range, 6 months-16 years) and 60% of the cases occurred between the ages of 7 and 12 years. Thirteen children (28%) had a past history of genitourinary malformations. The common malformations were hypospadias in eight children and bladder dysfunction in three. Ultrasound revealed no new urinary tract abnormalities in the remaining 34 children. Urinalysis were performed in 27 children, nine of whom (33%) had pyuria. Urine culture was positive in two children. Of the nine children with genitourinary malformations, eight had pyuria. All 18 children without genitourinary malformations had a negative urinalysis except for one patient (p< 0.0001). (Conclusions) Acute epididymitis is a common cause of acute scrotum in pediatric patients. In this study, one-third of acute epididymitis cases presented pyuria, and about 30% had a past history of genitourinary malformations. The presence of pyuria was associated with a past history of genitourinary malformations. For children with no previous genitourinary malformations, routine use of ultrasound for the detection of urinary tract abnormalities is questionable due to the low yield.
