A six-year-old girl with Turner's syndrome and proteinuria

A 6-year-old girl with Turner's syndrome presented with recent onset of proteinuria and pedal edema. There was no history of arthritis, fever, or abdominal pain. A physical examination revealed the stigmata of Turner's syndrome, hepatomegaly, and pedal edema. The urine contained 4+ protein without red blood cells or casts, and the BUN and creatinine were mildly elevated. The serum lipids were normal. An excretory urogram showed bilaterally enlarged, smooth kidneys without calyceal distortion. Because the proteinuria failed to respond after 1 month of steroid therapy, a diagnostic procedure was performed.