Hepatic peliosis

Hepatic peliosis is a rare benign vascular condition characterised by dilatation of sinusoidal blood filled spaces within the liver.  There may be involvement of other organs, most commonly the spleen and bone marrow.  It can be seen in a variety of settings and is important as appearances may mimic malignancy. 

As the causes of peliosis are varied, the demographics will reflect the underlying cause.

Patients are usually asymptomatic 6 and thus the condition is discovered incidentally on imaging or autopsy. In some instances, lesions may be complicated by haemorrhage presenting acutely, or result in hepatomegaly or liver impairment.

The pathogenesis remains uncertain, with possible aetiologies including the breakdown of the sinusoidal borders, hepatic outflow obstruction and dilatation of the central vein of the hepatic lobule.

Histologically, hepatic peliosis is characterised by multiple mottled blood-filled cyst-like spaces within the liver with associated sinusoidal dilatation 1-2. These vary in size from a <1 mm to several centimetres in diameter.

Macroscopically, the liver appears dark or even purple, and usually, the entire liver is involved to a greater of lesser degree. Focal lesions may demonstrate central areas of haemorrhage.

Aetiology
  • idiopathic: 20-50% 
  • toxins
    • arsenic
    • polyvinyl chloride (PVC)
    • thorium oxide
  • drugs
    • anabolic steroids
    • azathioprine
    • corticosteroids
    • diethylstilbestrol (DES)
    • immunoglobulin therapy
    • methotrexate
    • oral contraceptives
    • tamoxifen
    • 6-thioguanine (6-TG)
    • 6-mercaptopurine (6-MP)
  • chronic illness
  • infection in AIDS
    • bacillary peliosis caused by Bartonella henselae, Bartonella quintana and Rochalimaea henselae
  • other 
    • renal or cardiac transplantation

Unfortunately, appearances are nonspecific with variable enhancement patterns. Typically, there are multiple lesions, ranging from a few large lesions to innumerable small lesions.

Ultrasound

Sonographic appearances are nonspecific, usually demonstrating an irregular hypoechoic region/mass 2.

CT

Appearance on pre-contrast CT is variable, depending on liver density, but is usually of multiple hypoattenuating lesions of variable size. Central haemorrhage may lead to areas of hyperattenuation and even dystrophic calcification 1.

Following contrast administration, there is usually globular centripetal or centrifugal arterial enhancement with no washout, the lesion remaining slightly hyperattenuating compared to surrounding liver on portal venous phase 1. Enhancement may be uniform or peripheral or irregular, but in contrast to cavernous hemangioma, it is usually continuous. There is no mass effect on neighbouring hepatic vessels 6.

MRI

Signal characteristics may be altered due to the presence of haemorrhage; however, in general:

  • T1: typically hypointense (unless complicated by recent haemorrhage)
  • T2: hyperintense
  • C+ (Gd): enhancement is typical, and is usually centrifugal (from centre outward)
Angiography/DSA
  • hypervascular with multiple vascular nodules

It is important not to drain peliosis, having mistaken it for a hepatic abscess, as haemorrhage can be life threatening 7

Treatment depends on the cause. When a causative drug/toxin is suspected, withdrawal of that agent may result in resolution. If seen in the setting of HIV/AIDS, antibiotic treatment may be effective in eradicating B. henselae. If focal and haemorrhagic, resection may also be beneficial 1.

Complications 

From the Greek word pelios, meaning "dusky" or "purple" 1.

General imaging differential considerations include:

Share article

Article information

rID: 8027
Section: Pathology
Synonyms or Alternate Spellings:
  • Peliosis hepatis

Support Radiopaedia and see fewer ads

Cases and figures

  • Drag
    Hepatic peliosis: T2
    Case 1: T2
    Drag here to reorder.
  • Drag
    Hepatic peliosis:...
    Case 1: T1
    Drag here to reorder.
  • Drag
    Hepatic peliosis:...
    Case 1: T1 dynamic enhanced
    Drag here to reorder.
  • Drag
    Hepatic peliosis ...
    Case 2: T1 OP
    Drag here to reorder.
  • Drag
    Case 2: T2 FS
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.