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Polycystic Kidney Disease

Two major types: Autosomal Dominant Polycystic Kidney Disease (Adult Polycystic Kidney Disease [APKD] and Autosomal Recessive Polycystic Kidney Disease (Infantile Polycystic Kidney Disease) 

Autosomal Dominant Polycystic Kidney Disease

  • Is a slowly progressive disease with nearly 100% penetrance

  • Potter Type III

  • Cause: gene located on short arm of chromosome 16 (in 90%

    • Spontaneous mutation in 10%

  • Incidence:1:1,000 people carry the mutant gene

    • 3rd most prevalent cause of chronic renal failure

  • Histo: abnormal rate of tubule divisions (Potter Type III) with hypoplasia of portions of tubules left behind as the ureteral bud advances; cystic dilatation of Bowman capsule, loop of Henle, proximal convoluted tubule, coexisting with normal tissue

  • Mean age at diagnosis: 43 years (neonatal / infantile onset has been reported)

  • M:F = 1:1

  • Onset of cyst formation:

    • 54% in 1st decade

    • 72% in 2nd decade

    • 86% in 3rd decade

Associated with:

·     Cysts in: liver (25-50%), pancreas (9%)

·        Aneurysm: saccular "berry" aneurysm of cerebral arteries (3-13%)

·        Mitral valve prolapse

·        Hypertension (50-70%)

·        Azotemia

·        Hematuria, proteinuria

·        Lumbar / abdominal pain

·        Bilaterally large kidneys with multifocal round lesions; unilateral enlargement may be the first manifestation of the disease

Polycystic Kidney Disease

Adult Polycystic Kidney Disease Multiple low attenuation cystic lesions are seen in both
kidneys and throughout the liver.

·     Cysts may calcify in curvilinear rim- / ringlike irregular amorphous fashion elongated + distorted + attenuated collecting system nodular puddling of contrast material on delayed images

·        "Swiss cheese" nephrogram = multiple lesions of varying size with smooth margins

·        Polycystic kidneys shrink after beginning of renal failure, after renal transplantation, or on chronic hemodialysis

·     NUC: poor renal function on Tc-99m DTPA scan   


·     Multiple cysts in cortical region (usually not seen prior to teens)

·        Diffusely echogenic when cysts small (children)

·        Renal contour poorly demarcated


·     Large echogenic kidneys similar to infantile PCKD (usually in 3rd trimester, earliest sonographic diagnosis at 14 weeks), can be unilateral

·        Macroscopic cysts (rare)

·        Normal amount of amniotic fluid / oligohydramnios (renal function usually not impaired)


·        Death from uremia (59%) / cerebral hemorrhage (secondary to hypertension or ruptured aneurysm [13%]

·        Renal calculi

·        Urinary tract infection

·        Cyst rupture

·        Hemorrhage

·        Renal cell carcinoma (increased risk)

 Differential Diagnosis

·     Multiple simple cysts (less diffuse, no family history)

·        von Hippel-Lindau disease (cerebellar hemangioblastoma, retinal hemangiomas, occasionally pheochromocytomas)

·        Acquired uremic cystic disease (kidneys small, no renal function, transplant)

·     Infantile PCKD (usually microscopic cysts) 


Autosomal Recessive Polycystic Kidney Disease = Polycystic Disease of Childhood

·     Potter Type I

·        Incidence:1: 6,000 to 1:50,000 livebirths

·    F > M; carrier frequency of 1:112


·        Kidney: abnormal proliferation + dilatation of collecting tubules resulting in multiple 1- to 2-mm cysts

·        Liver: periportal fibrosis often with abnormal proliferation + dilatation of bile ducts

·        Pancreas: pancreatic fibrosis

ANTENATAL FORM (most common)

·     90% of tubules show cystic changes

·        Onset of renal failure in utero

·        Potter sequence

·        Oligohydramnios and dystocia (large abdominal mass)

·        Prognosis: death from renal failure / respiratory insufficiency (pulmonary hypoplasia) within 24 hours in 75%, within 1 year in 93%; uniformly fatal


·     60% of tubules show ectasia + minimal hepatic fibrosis + bile duct proliferation

·        Onset of renal failure within 1st month of life

·        Prognosis: death from renal failure / hypertension / left ventricular failure within 1st year of life


·     20% of renal tubules involved + mild / moderate periportal fibrosis

·        Disease appears by 3-6 months of age

·        Prognosis: death from chronic renal failure / systemic arterial hypertension / portal hypertension


·     10% of tubules involved + gross hepatic fibrosis + bile duct proliferation

·        Disease appears at 1-5 years of age

·        Prognosis: death from portal hypertension

·        The less severe the renal findings, the more severe the hepatic findings!


·        Severe pulmonary hypoplasia

·        Pneumothorax / pneumomediastinum


·        Portal venous hypertension

·        Tubular cystic dilatation of small intrahepatic bile ducts

·        Increase in liver echogenicity (from congenital hepatic fibrosis)


·        Bilateral gross renal enlargement

·        Faint nephrogram + blotchy opacification on initial images

·        Increasingly dense nephrogram

·        Poor visualization of collecting system

·        "Sunburst nephrogram" = striated nephrogram with persistent radiating opaque streaks (collecting ducts) on

·        Delayed images

·        Prominent fetal lobulation


·        Prolonged corticomedullary phase


·        Hyperechoic enlarged kidneys (unresolved 1- to 2-mm cystic / ectatic dilatation of renal tubules increase number of acoustic interfaces)

·        Increased renal through-transmission (high fluid content of cysts)

·        Loss of corticomedullary differentiation, poor visualization of renal sinus + renal borders

·        Occasionally discrete macroscopic cysts <1 cm

·        Compressed / minimally dilated collecting system

       OB-US (diagnostic as early as 17 weeks GA):

·        Progressive renal enlargement with renal circumference : abdominal circumference ratio >0.30

·        Hyperechoic renal parenchyma

·        Nonvisualization of urine in fetal bladder (in severe cases)

·        Oligohydramnios (33%)

·        Small fetal thorax

   OB management

·        Chromosome studies to determine if other malformations present (e.g., trisomy 13 / 18)

·        Option of pregnancy termination <24 weeks

·        Nonintervention for fetal distress >24 weeks if severe oligohydramnios present

·        Risk of recurrence:25%

·        DDx: Meckel-Gruber syndrome, adult polycystic kidney disease