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multicystic renal dysplasias


Thursday 19 February 2004

Multicystic renal dysplasia (MRD) is a malformative condition of the kidneys characterized by an abnormal metanephric differentiation and a renal cystogenesis. It can be associated with obstructive uropathy (obstructive MRD) or not (non-obstructive MRD).

Multicystic renal dysplasia is a form of renal dysplasia characterized by the presence of multiple cysts of varying size in the kidney and the absence of a normal pelvocaliceal system. It is a form of severe generalized corticomedullary maldifferentiation affecting the whole of one or both kidneys.

Multicystic renal dysplasia is the most common form of cystic renal disease in the newborn period. Most cases are detected during infancy and it represents the most common cause of flank mass in an infant.

MRD can be associated with renal obstruction (obstructive MRD), such as reflux nephropathy, or it can occur in a setting without obstructive uropathy (non-obstructive MRD). In the latter case, it is mostly bilateral (bilateral non-obstructive renal dysplasia, BNORD) and can be observed as an isolated defect or associated with other malformative syndromes, such as Meckel syndrome (MKS) and Bardet-Biedl syndrome (BBS) amongst others.


- obstructive MRD (OMRD) (associated with obstructive uropathy)
- non-obstructive MRD (NOMRD) (not associated with obstructive uropathy)


- bilateral multicystic renal dysplasia (BMRD)
- unilateral multicystic renal dysplasia (UMRD)


- multiple cysts of varying size in the kidney

  • large cysts are distributed beneath the renal capsule

- pelvicaliceal system severely attenuated pr absent reflecting the diminution of the branching of the ureterci bud during renal organogenesis

Case records

- Case 12763: Non-syndromic bilateral non-obstructive multicystic renal dysplasia

See also

- renal dysplasias
- bilateral diffuse multicystic kidneys


- Bisceglia M, Galliani CA, Senger C, Stallone C, Sessa A. Renal cystic diseases: a review. Adv Anat Pathol. 2006 Jan;13(1):26-56. PMID: 16462154

- Matsell DG, Bennett T, Goodyer P, Goodyer C, Han VK. The pathogenesis of multicystic dysplastic kidney disease: insights from the study of fetal kidneys. Lab Invest. 1996 May;74(5):883-93. PMID: 8642784

- emedicine
- MIM.143400