Search our site 
Advanced Search

Home | Contact us | About us |


You are in Home >> Key Topics >> Miscellaneous

Medullary sponge kidney

Created: 6/11/2005


Medullary Sponge Kidney (MSK)

  • Recognized by Beitzke in 1908
  • Radiographic features described by Lenarduzzi in 1939
  • Nomenclature for this disorder from Cacchi and Ricci in 1949

Characteristic features:

  • Dilatation of the distal portion of the medullary collecting ducts with associated cysts and diverticula
  • The dilated ducts have the appearance of bristles on a brush
  • Collecting ducts can be more ectatic and filled with calcifications, giving an appearance suggestive of a "bouquet of flowers."
  • NB This appearance sometimes termed "precalyceal canalicular ectasia"


  • Unknown – many patients asymptomatic
  • Estimated incidence in the general population between 1 in 5000 and 1 in 20,000


  • The principal finding is dilated intrapapillary collecting ducts and small medullary cysts, which range in diameter from 1 to 8 mm and give the cross-sectioned kidney the appearance of a sponge


  • Not considered a genetic disease
  • Small number of isolated reports of autosomal dominant and autosomal recessive inheritance
  • Associated with rare congenital anomalies such as hemihypertrophy, Beckwith-Wiedemann syndrome (macroglossia, omphalocele, and gigantism), Ehler-Danlos syndrome, anodontia, and Caroli's disease

Clinical Features

Usually presents after 20 years

  • Renal colic (55%)
  • UTI (25%) (more common in females)
  • Macroscopic haematuria (15%)

NB Patients with MSK more likely to form urinary stones (of patients with MSK females more commonly affected)

Stones usually composed of calcium oxalate either alone or in combination with calcium phosphate


IVU is more sensitive than CT in detecting mild cases of MSK

The urographic features:

  • Enlarged kidneys, sometimes with calcification, particularly in the papillae
  • Elongated papillary tubules or cavities that fill with contrast medium
  • Papillary contrast blush and persistent medullary opacification (in some cases the papillae resemble bunches of grapes or bouquets of flowers, and in others discrete linear stripes appear that can be counted readily)


Aimed at complications of MSK ie calculi and infection

NB Many have hypercalciuria and may require thiazide diuretics

Thiazides are effective for lowering hypercalciuria and limiting stone formation. If thiazides cannot be used, inorganic phosphates may be appropriate. For those patients with renal lithiasis, thiazides should be administered even if hypercalciuria is not present


Original estimates were that 10% of symptomatic patients with MSK have a poor long-term prognosis because of nephrolithiasis, septicemia, and renal failure NB figure probably lower due to more effective treatments for hypercalciuria and renal lithiasis and because of the better antibiotics available and the selective use of prophylaxis

SiteSection: Article

Login Status  

You are not currently logged in.
UK/Ireland Registration
Overseas Registration

  Forgot your password?

All rights reserved © 2008.

UrologyUK has been developed by AnaesthesiaUK.