Liver abscesses and cysts

Question 1

Define liver abscess/cyst.

Answer 1

Liver infection resulting in walled off collection of pus or cyst fluid.

Question 2

What are the risk factors for liver abscesses?

Answer 2

• Biliary tract disease
• Age >50 years
• Underlying malignancy
• DM
• Interventional biliary or hepatic procedures
• Living or visiting an area endemic for amoebiasis

Other:

• Cirrhosis
• Liver transplantation
• Alcoholism - may increase risk
• Male sex
• Cardiopulmonary disease
• Immunocompromised
• Penetrating abdominal trauma
• IBD, pancreatitis, appendicitism diverticulitis or peritonitis
• Bacteraemia,endocarditis or intravascular infection

Question 3

What is the aetiology of liver abscesses?

Answer 3

Iatrogenic

Pyogenic - E coli, Klebsiella, enterococcus, bacteroides, streptococci, staphylococci. 60% caused by biliary disease (gallstones, strictures, congenital cysts), cyryptogenic (15%)

Amoebic - Entamoeba histolytica

Hydatid cyst - Tapeworm Echinococcus granulosis

Other - Tuberculosis, fungal due to candida.

Question 4

What is the most common underlying condition in people with pyogenic liver abscesses?

Answer 4

Biliary tract disease

Question 5

When do fungal liver abscesses usually occur?

Answer 5

In immunocompromised hosts

Question 6

How common are liver abscesses?

Answer 6

Pyogenic - incidence 0.8 in 100,000 with mean age 60 years, most common liver abscess in industrialised world.

Amoebic - most common type worldwide (10% of world’s population has been infected)

Hydatid disease - common in sheep-rearing countries

Question 7

What is the pathophysiology of liver abscesses?

Answer 7

Liver abscesses form by spread of infection from 1 of the following sources:

• Biliary tree
• Portal vein - drains GI tract, gall bladder and pancreas.
• Hepatic vein
• Extension of contiguous infection
• Penetrating trauma incl. iatrogenic

Question 8

How do liver abscesses present?

Answer 8

• Fever, malaise, nausea, anorexia, night sweats, weight loss
• RUQ pain or epigastric pain which may be referred to shoulder (diaphragmatic irritation)
• Jaundice, diarrhoea, pyrexia of unknown origin
• Ask about foreign travel

Question 9

What are the signs of liver abscesses on examination?

Answer 9

• Fever (continuous or spiking), jaundice
• Tender hepatomegaly, right lobe affected more commonly than left
• Dullness to percussion and decreased breath sounds at right lung base caused by reactive pleural effusion

Question 10

What investigations would you do for liver abscesses/cysts?

Answer 10

Bloods:

• FBC - mild anaemia, leukocytosis, increased eosinophils in hydatid disease
• LFTs - increased AlkPhos, high bilirubin
• Raised ESR and CRP
• Blood cultures
• Amoebic and hydatid serology

Stool microscopy, cultures - for E histolytica and tapeworm eggs

Imaging:

Liver US or CT/MRI - localises structure of mass

CXR - right pleural effusion or atelectasis, raised hemidiaphragm

Invasive:

Aspiration and culture of abscess material - most pyogenic liver abscesses are polymicrobial. Amoebic abscesses contain anchovy sauce fluid of necrotic hepatocytes and trophozoites

Question 11

What is the diagnosis?

A healthy 55-year-old man presents with a 1-week history of fevers, chills, fatigue, and anorexia, followed by right shoulder pain, paroxysmal cough, and generalised abdominal pain. He is ill-appearing, and his physical examination is notable for a temperature of 38.3°C (101°F) and a tender liver edge that is palpated approximately 2 cm below the right costal margin. Percussion or movement worsens the pain.

Answer 11

Liver abscess = most common presenting symptoms are fever, chills, and RUQ pain. Right-sided pulmonary symptoms may also occur. Can present in an insidious manner.

Question 12

What is the management of a liver abscess?

Answer 12

Antibiotics - IV metronidazole + cefuroxime/ciprofloxacin - antibiotics initially IV then 4-6weeks oral

Drainage - needle aspiration under USS, indwelling catheter under CT guidance, open or laparoscpic surgery.

NB: for abscesses <3cm, abx alone may be sufficient to treat the abscess.

Question 13

What are the complications of liver abscess?

Answer 13

• Metastatic complications - more common with Klebsiella
• Sepsis
• Abscess rupture
• Subphrenic abscess
• Fistula to adjacent organs
• Hepatic artery pseudoaneurysm
• Abdominal or hepatic venous thrombosis
• Liver failure
• Acute pancreatitis
• Abscess recurrence

Question 14

Which genetic condition commonly presents with liver cysts?

Answer 14

ADPKD

Question 15

What are some differentials for a liver cyst?

Answer 15

• Mucinous cystic neoplasm
• Necrotic malignancy
• Hepatic abscess
• Haemangioma
• Hamartoma

Question 16

How do you diagnose liver cysts?

Answer 16

Usually imaging is sufficient

If suspicious → aspiration for cytology

Question 17

Do patients with liver cysts need follow up?

Answer 17

Usually no as simple cysts do not have malignant potential

Question 18

What are the causes of liver cysts?

Answer 18

• Infectious e.g. parasitic or non parasitic as discussed in previous cards
• Polycystic liver/kidney disease
• Von Hippel Lindau
• Old age
• Female
• Estrogen exposure - multiple pregnancy, oral contraceptives, HRT

Question 19

What are the clinical features of liver cysts?

Answer 19

Usually asymptomatic

If large → hepatomegaly, abdo pain, bile duct infections or obstruction

Rarely haemorrhage, rupture, infection