Presentation
Abdominal pain. On Us, there's bilateral hydronephrosis, more on the right.
Patient Data
IVP shows numerous dilated, polygonal-shaped calyces in both kidneys (more evident on the right side) with convex outer margins. The renal pelves and ureters are not dilated and appear normal in size helping to differentiate this condition from a cause of obstructive hydronephrosis.
Right renal upper calyceal stone.
Findings are suggestive of renal megacalycosis/congenital magacalyces.
Case Discussion
Congenital megacycles or megacalycosis is a rare congenital disease caused by the underdevelopment of renal medullary pyramids.
Radiographic features of the disease:
- numerous crowded dilated, and polygonal renal calyces which show convex outer margins (secondary to the absence of medullary pyramids)
- the renal pelvis and ureter are of normal size helping to distinguish megacalyces from hydronephrosis.