Robert L. Lebowitz, M.D.
Children' s Hospital, Harvard Medical School
Boston, Massachusetts

Four Distinct Congenital Abnormalities in a Left Kidney

A boy was found to have hydronephrosis in utero and after delivery VCUG showed reflux into the lower pole of a left duplex kidney. There was a distal, normal calibre, aperistaltic segment (Figure 1) suggesting distal ureteral obstruction, a marked difference in the density of contrast material between the ureter and the dilated pelvicalyceal system (Figure 2) suggesting UPJ obstruction. The contrast material became diluted by the nonopaque urine trapped above the UPJ obstruction. Thus, the four conditions were :
  1. Duplex kidney
  2. Lower pole reflux
  3. Lower pole UVJ obstruction, and
  4. Lower pole UPJ obstruction
A drainage film with a catheter in the bladder after the VCUG (Figure 3) showed that the contrast material was trapped in the pelvicalyceal system and the ureter down to the level of the aperistaltic segment.

An IVP (Figure 4), with a catheter in the bladder to prevent artifacts that reflux can cause, showed a normal right kidney, a normal left upper pole, and poor visualization of the dilated lower pole. A renal scan showed significant function remaining in the lower pole, and so the boy underwent one operation that solved all of the problems. A lower-to-upper pyeloureterostomy was performed with excision of most of the lower pole ureter. A post-operative IVP showed relief of obstruction and good function of the lower pole, while the upper pole remained normal. A VCUG showed reflux only into a tiny, short lower pole stump.(Figure 5 ) and (Figure 6).


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