Hepatic AD Polycystic Kidney Disease

Michael P. Federle, MD, FACR

Key Facts

Terminology

Part of fibropolycystic liver (and renal) disease spectrum

Imaging

Extent of hepatic involvement ranges from scattered cysts to diffuse replacement of liver
- ± cysts in kidneys and other organs
Cyst contents often greater than water density due to hemorrhage (infection less common)
- Calcification in cyst wall often seen (due to old hemorrhage)
Cysts have very low signal intensity on T1WI
- Higher signal with recent hemorrhage
Homogeneous high signal intensity on T2WI
- Intracystic hemorrhage: Lower signal intensity in T2WI

Top Differential Diagnoses

Hepatic (bile duct) cysts
Biliary hamartoma
Caroli disease
Cystic metastases

Clinical Issues

Dull abdominal pain, abdominal distention, dyspnea, cachexia, early satiety
Often causes massive hepatomegaly, compression of stomach
- Liver volume often 5-10x higher than normal
Liver progressively enlarges as it is replaced by cysts
Treatment: Surgical marsupialization &/or resection of dominant cysts
- Orthotopic liver transplantation has excellent long-term results

(Left) Gross pathology photograph of a hepatectomy specimen shows numerous cysts replacing liver parenchyma. The cysts ranged in size from microscopic to 5 cm in greatest dimension and contained clear fluid. This liver, which weighed 9 kg, was resected due to intractable patient discomfort and pressure on other organs. (Right) Coronal T2WI MR shows innumerable high signal intensity cysts of varying size almost completely replacing hepatic parenchyma. Multiple cysts

within the left kidney are also visible.

(Left) Axial CECT shows typical findings of ADPLD in a middle-aged man with early satiety. Note the compression of the stomach

by a dominant cyst

from the left hepatic lobe, which was subsequently marsupialized at surgery with resolution of symptoms. (Right) Axial CECT in the same patient following surgical drainage of the left lobe cyst shows no residual compression of the stomach

. The symptoms of early satiety also resolved.

TERMINOLOGY

Abbreviations

Autosomal dominant polycystic liver disease (ADPLD) or adult PLD

Definitions

Uncommon inherited disorder
Part of fibropolycystic liver disease spectrum
- Constitutes group of related lesions of liver and biliary tract caused by abnormal development of embryological ductal plate

IMAGING

General Features

Best diagnostic clue
- Multiple (> 20) cysts of varying size
Location
- Extent of hepatic involvement ranges from limited sporadic areas of cystic disease to diffuse involvement of all lobes of liver
  - ± cysts in kidneys and other organs
Size
- Range from < 1 mm to > 12 cm
Key concepts
- Numerous large or small cysts coexist with fibrosis
  - Round or oval shape
  - Smooth thin wall (if uncomplicated)
  - Absence of internal structures (if uncomplicated)

CT Findings

NECT
- Multiple to innumerable, homogeneous, and hypoattenuating cystic lesions
  - Cyst contents > water density due to hemorrhage (infection less common)
  - Calcification in cyst wall often seen (due to old hemorrhage)
CECT
- No wall or content enhancement
- Cysts complicated by infection or hemorrhage may have septations &/or internal debris
  - May also have enhancement of walls
- Cysts may contain fluid levels