Infected renal hematoma in a healthy adolescent with no renal structural anomaly

Renal abscesses are uncommon in otherwise healthy children and adolescents who have no underlying renal structural anomalies. A previously healthy, immunocompetent, 14-year-old male without a history of abdominal trauma or urinary tract infection (UTI) was found to have a renal hematoma that became infected and developed into a renal abscess. He presented with a 2-day history of nausea, vomiting, fever and 1-day history of abdominal pain that radiated to the right flank. Clinical examination, blood work, and initial imaging indicated likely infection; however, findings were normal on urinalysis and urine culture had no growth. Complete blood count (CBC) showed a leukocytosis with a left shift. Renal ultrasound showed a 4-cm mass-like area of liquefaction in the upper pole of the right kidney, confirmed by abdominal computed tomography (CT) scan with and without contrast. Intravenous ceftriaxone was started and the patient continued to improve. He was discharged on hospital day 6 after remaining afebrile for over 20 hours and inflammatory markers continued to decrease. Intravenous ceftriaxone was continued, and oral clindamycin was added. Both antibiotics were discontinued on day 24 since onset of illness.