A 7-year-old girl with periodic flank discomfort.

A7-year-old girl with a 12-month history of intermittent left flank pain was transferred to our institution from an outside hospital. Severe pain occurred about once per month and was associated with multiple episodes of nonbloody, nonbilious emesis. The pain did not radiate and was not alleviated or exacerbated by anything else. Symptoms lasted 2 to 3 days and then gradually resolved. The patient denied associated dysuria, hematuria, fever, or diarrhea. The patient had visited her pediatrician’s office several times, but diagnostic work-ups for urinary tract infection and constipation were negative. A recent renal ultrasound revealed severe left hydronephrosis. Due to recurrent pain, the patient was seen at an outside hospital, where a computed tomography (CT) scan was ordered (Figure 1). Her most current painful episode started 5 days prior to admission. Initial physical examination revealed a well-developed and well-nourished child with normal vital signs, including normal blood pressure. Her anthropometric parameters were within normal limits for age. HEENT (head, eyes, ears, nose, and throat) examination, respiratory examination, and cardiovascular examination were all unremarkable. On abdominal examination there was left costo-vertebral angle tenderness but no palpable mass. Her neurologic assessment was normal. No rashes or skin lesions were present. A 7-Year-Old Girl with Periodic Flank Discomfort