MULTICYSTIC RENAL
DYSPLASIA
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Multicystic renal dysplasia (MCRD) is a rare lesion of the renal parenchyma
occurring in 1:10,000 births.
- Sporadic or as a recurrent
familial trait.
- Pathogenesis
Unknown, but thought to due to obstruction in most cases (1).
Link to Classification
ULTRASOUND OF THE CLASSICAL FORM
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- Unilateral or rarely
bilateral (2).
- Multiple renal cysts (due
to segmental blocking of collecting tubules and surrounding dysplastic
renal parenchyma) - "cluster of grapes".
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![](9-019_files/image002.jpg)
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Unilateral
Multicystic renal dysplasia
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![](9-019_files/image004.jpg)
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Bilateral multicystic renal dysplasia
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![](9-019_files/image006.jpg)
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![](9-019_files/image008.jpg)
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![](9-019_files/image010.jpg)
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![](9-019_files/image012.jpg)
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Multiple cysts of varying size
No communication between cysts
Large kidney
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![](9-019_files/image014.jpg)
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Normal contralateral kidney
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- May affect the entire
kidney or only a portion of the kidney(segmental) and urine
production is therefore variable.
Segmental multicystic renal dysplasia
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![](9-019_files/image016.jpg)
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Multicystic
renal dysplasia lower pole left kidney
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Normal
right kidney
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![](9-019_files/image018.jpg)
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![](9-019_files/image020.jpg)
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![](9-019_files/image022.jpg)
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- The cysts are of varying
size and shape and distributed in an irregular pattern throughout the
kidney. Large peripheral cysts enlarge and distort the reniform contour
("bunch of grapes").
- The cysts are non
communicating, with areas of echogenicity typically surrounding the
cysts.
![](9-019_files/image024.jpg)
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Multiple non
communicating cyst
Peripheral
location
No central
renal pelvis
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![](9-019_files/image026.jpg)
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![](9-019_files/image028.jpg)
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![](9-019_files/image030.jpg)
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![](9-019_files/image032.jpg)
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Size of cysts variable, but may reach
considerable dimensions and appear to occupy a large portion of the abdominal
cavity.
- Echogenic areas within the
affected kidney reflect the presence of calcification in the areas of missing
tissue.
- No normal renal parenchyma
is discernible (especially with advanced disease).
- Kidney size may be normal,
small or enlarged.
- The renal pelvis and ureter
are not visualized.
- The ipsilateral renal
artery is hypoplastic or atrophic.
- Amniotic fluid normal in
unilateral disease.
- Marked oligohydramnios in
bilateral disease, which is invariably fatal.
Classical multicystic renal dysplasia
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![](9-019_files/image048.jpg)
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![](9-019_files/image050.jpg)
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![](9-019_files/image052.jpg)
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![](9-019_files/image054.jpg)
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![](9-019_files/image056.jpg)
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Pathological
Specimen
- Multiple non-communicating cysts.
- No renal cortex.
- Atresia of the mid ureter.
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![](9-019_files/image058.jpg)
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Non functioning kidney on nuclear medicine scan
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![](9-019_files/image059.jpg)
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ULTRASOUND OF THE ATYPICAL FORM
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- Difficult to distinguish from
hydronephrosis as the renal pelvis communicates with peripheral cysts
which resemble dilated calyces.
Link to Associated Anomalies
- Hydronephrosis.
The classical form is easily distinguished from hydronephrosis. In
hydronephrosis, the reniform shape of the kidney is preserved, normal
renal parenchyma is present peripherally and the cystic areas are
anatomically aligned and communicate with a dilated renal pelvis. the
ureter may also be dilated in distal obstructions.
- Trisomy
13.
- -30% have cystic
kidneys.
- Meckel-Gruber syndrome.
Bilateral cystic kidneys, oligohydramnios, cleft lip, microcephaly and
cephalocele.
- Less commonly cystic
renal dysplasia has been reported in several chondrodysplasia syndromes,
Roberts syndrome, Jeune syndrome, trisomy 9, Zellweger syndrome, Ivermark
syndrome, type 2 glutaric aciduria.
- Rizzo N, Gabrielly S, Pilu
G et.al. Prenatal diagnosis and obstetrical management of multicystic
dysplastic kidney disease. Prenat Diagn 1987;7:109.
- D'Alton ME, Romero R,
Grannum P et.al. Antenatal diagnosis of renal anomalies by ultrasound. IV:
Bilateral multicystic kidney disease. Am J Obstet Gynecol 1986;54:532.