Kidney nontumor / medical renal
Developmental & cystic diseases
Dysplasia / hypoplasia / agenesis
Author: Mandolin S. Ziadie, M.D.
Last author update: 1 December 2011
Last staff update: 21 July 2023 (update in progress)
Copyright: 2003-2023, PathologyOutlines.com, Inc.
PubMed Search: Cystic renal dysplasia
Table of Contents
Definition / general | Epidemiology | Clinical features | Case reports | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Differential diagnosis | Additional referencesCite this page: Ziadie MS. Dysplasia / hypoplasia / agenesis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/kidneytumorcysticrenaldysplasia.html. Accessed September 22nd, 2023.
Definition / general
- Congenital cystic anomaly of the kidney caused by abnormal metanephric differentiation, occurring by week 20 in utero
- Enlarged, cystic kidneys with disorganized parenchyma and numerous cysts
- Immature tubules surrounded by mesenchymal collars and islands of immature mesenchyme are present between the cysts
- Also known as multicystic renal dysplasia
Epidemiology
- Most common pediatric cystic renal disease
- Most often a sporadic event but familial cases have been reported
- 90% are associated with ureteropelvic obstruction, ureteral agenesis, atresia or reflux; 10% have unknown cause
- Bilateral disease should raise the suspicion of occult disease in parents
- Also associated with cardiac malformations, Meckel-Gruber syndrome (eMedicine), inherited metabolic abnormalities (Pediatr Nephrol 2007;22:2119), thanatophoric dysplasia type 1 (Genet Couns 2006;17:407) and other familial syndromes (Am J Med Genet 1996;63:332)
Clinical features
- Most common cause of neonatal abdominal masses; presents as flank mass or pyelonephritis
- In bilateral disease, neonates may also display oligohydramnios and pulmonary hypoplasia
- If blastema present, patient is at a slightly higher risk for Wilms tumor
- Segmental dysplasia is seen in children with duplex (duplicated) kidney (incomplete fusion of upper and lower poles)
Case reports
- Newborn with bilateral renal dysplasia, severe pancreatic fibrosis, intrahepatic biliary dysgenesis and total situs inversus with normal cytogenetics (Hum Pathol 1988;19:871)
Gross description
- Enlarged kidney distorted by variably sized cysts that may involve one or both (20%) kidneys
- Indistinct corticomedullary junction
- Usually associated with ureteropelvic obstruction or ureteral atrophy / atresia
Gross images
Images hosted on other servers:
Multiple cysts of various sizes
With small bladder
Cysts are smooth
lined, no normal
kidney tissue
is apparent
With ipsilateral hypoplasia of ureter
Due to congenital
urethral stenosis with
hypertrophic bladder wall
and bladder diverticulum
Microscopic (histologic) description
- Disorganized parenchyma that is distorted by cysts of various sizes, lined by flattened to cuboidal epithelium
- May contain nodular blastema (undifferentiated cells), islands of undifferentiated mesenchyme, cartilage (10% - 20%), immature collecting ducts with fibromuscular collars and primitive glomerular structures
Microscopic (histologic) images
Images hosted on other servers:
Large cysts lined by
flattened epithelium
with fibrotic and
cartilaginous stroma
Islands of cartilage in stroma
Multiple small cysts and
immature tubules, surrounded
by immature connective tissue with
abortive glomerular structures
Immature mesenchyme and cysts
Differential diagnosis
- Autosomal dominant polycystic kidney disease: familial, adults, rarely presents at birth; alterations in PKD1, PDK2 or PKD3
- Autosomal recessive polycystic kidney disease: familial, uniform cysts in neonates, cysts are radially arranged, no immature mesenchyme or cartilage; abnormalities in PKHD1 gene
- Cystic nephroma: sharply demarcated from adjacent kidney by thick fibrous capsule, no renal tissue between cysts, no immature mesenchyme or cartilage
- Cystic partially differentiated nephroblastoma: epithelial and stromal elements and nephroblastomatous tissue; usually hyperdiploid with trisomy 12
Additional references
