Liver cysts and abscesses

Cysts

  • Hepatic cysts/abscesses encompass a spectrum of findings which can be incidental/of little relevance to those requiring urgent treatment
  • Lesions include:
    • Simple cysts- extremely common (~5%) and usually of no concern
      • Believed to be congenital; lined with biliary-type epithelium (thought to maybe be remnants of the biliary tree which did not end up connecting to the outflow
      • Filled with plasma-like fluid secreted by the epithelium.
      • Usually patients are asymptomatic and do not require any treatment (almost all will recur)
        • Rarely, they can cause right upper quadrant discomfort.  If symptoms do occur, the cyst can be treated by ‘de-roofing’ to allow drainage into the peritoneal cavity
    • Multiple cysts- may or may not be due to polycystic liver disease
      • Adult PLD is an autosomal dominant inherited condition associated with polycystic kidney disease (gene mutations in PKD1 and PKD2)
      • Kidney disease is usually present earlier and is more severe than liver disease.  Occasionally causes hepatomegaly and abdominal pain, rarely causes fibrosis and liver failure.
    • Neoplastic (tumour) cysts (rare)
    • Hydatid (echinococcal) cysts
      • Caused by infection of Echinococcus granulosus (a kind of worm which is carried by dogs and can infect humans, cows and sheep- most commonly seen in those who work with animals).
      • Usually asymptomatic, and infection can go unnoticed for years.  Can present with hepatomegaly and abdominal pain
      • Have a characteristic appearance on imaging of ‘daughter’ cysts within the main cyst.  Eosinophilia and antibody tests may also support the diagnosis
      • Treatment is with anti-parasitic medication e.g. Mebendazole

Abscesses

Background/Epidemiology

  • Uncommon and carry significant mortality/morbidity but are potentially curable
    • Mortality of between 20-40%; failure to make the diagnosis often contributes to the mortality
    • Annual incidence of ~2.3/100,000 people/year in the UK

Aetiology

  • Pyogenic
    • Most are secondary to problems elsewhere in the abdomen e.g.
      • Biliary obstruction (stones/stricture/malignancy) and cholangitis
      • Haematogenous via the portal vein (e.g. in mesenteric infections) or via the herpatic artery (as in systemic bacteraemia e.g. in endocarditis)
      • Iatrogenic e.g. liver biopsy or stent; or trauma
    • Other risk factors include
      • Diabetes, chronic liver disease (cirrhosis), immunosuppresion
    • Most common organisms include
      • Klebsiella pneumoniae and Escheria Coli. Bacteroides, enterococci and anaerobic streptococci may also be found
      • Fungal infections may be found in immunocompromised patients and Staph aureus/Haemolytic Strep may be found in patients where infective endocarditis may be the reason for septicaemia.
      • Often polymicrobial
    • More commonly affects the right hepatic lobe than the left.
  • Amoebic
    • Caused by Entamoeba histolytica. More common in developing countries but can rarely present without a travel history in the UK
    • Transmission is via the faecal-oral route.

Presentation

  • Generally unwell- fever, rigors, malaise, night sweats, anorexia,weight loss
    • Quite often, pyrexia of unknown origin is all that can be present
    • Fever may or may not be swinging
  • Abdominal pain (RUQ)
    • More common in amoebic abscesses than pyogenic
    • Occasionally radiates to the right shoulder and can be pleuritic
      • Occasionally, coughs or hiccups can be a problem caused by diaphragmatic irritation
    • Tender hepatomegaly
  • Mild jaundice can be present (more common in severe disease/multiple abscesses)

Investigations

  • Blood tests
    • FBC- anaemia (chronic disease); neutrophilic leucocytosis (NB eosinophilia is not often seen with amoebic disease)
    • LFTs- raised alkaline phosphatase, low albumin, raised ALT/AST, raised bilirubin
    • Blood cultures (will be positive in around 50%)
  • Imaging
    • Liver USS is often first line.  Further imaging (CT) is usually useful for further investigation e.g. aspiration
  • Needle aspiration (for microscopy and culture/sensitivity/serology for amoebiasis)
  • Other investigations which may be ordered as part of the workup include
    • CXR- may show a raised right hemidiaphragm
    • Stool culture can be investigated for signs of amoebiasis

Management

  • Antibiotics- Co-amoxiclav and Metronidazole
  • Drainage (percutaneous, CT/USS guided)
Advertisement

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: