Medullary Sponge Kidney

This 37 year-old lady, well known to the local renal unit was admitted with left loin pain. Her serum creatinine was elevated.
Medullary sponge kidney is a sporadic condition. The medullary and papillary portions of the collecting ducts are dysplastic and dilated.
Medullary nephrocalcinosis occurs in the majority of cases. It may be unilateral or bilateral and affect a single or multiple pyramids.
Clusters of pyramidal medullary calcification are characteristic.
A major complication of this condition is urolithiasis leading to acute presentation with ureteric calculi (as occurred in this case)
References:
1. Medullary Sponge Kidney, AN Khan, emedicine.com.
2. Dähnert W. Radiology Review Manual, p926, Lippincott.
Credit: Dr Ian Bickle
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