liver abscess

Question 1

definition of liver abscess

Answer 1

liver infection = walled off collection of pus

A localized infection in the liver parenchyma that may be bacterial, fungal, or parasitic in origin

Question 2

aetiology of liver abscess

Answer 2

Pyogenic: Escherichia coli, Klebsiella, enterococcus, bacteroides, streptococci, staphylococci. Sixty percent caused by biliary tract disease (gallstones, strictures, congenital cysts),cryptogenic (15%).

Amoebic: Entamoeba histolytica.

Hydatid cyst: TapewormEchinococcus granulosis.

Other: Tuberculosis

infection can spread to the liver through the biliary tree, hepatic vein, or portal vein from adjacent infection or because of trauma

fungal abscesses can occur in immunosuppressed

Recurrent pyogenic cholangitis (associated with hepatolithiasis) due to Salmonella typhi may cause pyogenic liver abscess

Abscesses caused by Klebsiella species have been associated with extrahepatic complications, including endophthalmitis and central nervous system infections.

Question 3

RF for liver abscess

Answer 3

• biliary tract disease
• >50yrs
• underlying malignancy
• dm
• interventional biliary/hepatic procedures
• living in or visiting area endemic for amebiasis
• cirrhosis
• cardiopulmonary disease
• immunocompromise

Question 4

pathophysiology of liver abscess

Answer 4

abscesses form from spread of infection from either

• biliary tree - most common
• protal vein
• hepatic vein
• extension of contiguous infection
• penetrating trauma

The portal vein drains the gastrointestinal tract, gallbladder, and pancreas.

Pylephlebitis (portal vein inflammation) from inflammatory bowel disease, pancreatitis, appendicitis, or diverticulitis can result in liver abscess.

A migrated foreign body can also be associated with liver abscess.

Question 5

epidemiology of liver abscess

Answer 5

pyogenic

• incidence 0.8 in 100000
• 60yrs
• most common in industrialised world

amoebic - most common worldwide

hydatid disease - common in sheep rearing countries

Question 6

Sx of liver abscess

Answer 6

fever

nausea

malaise

anorexia

night sweats

weight loss

RUQ/epigastric pain - may be referred to shoulder (diaphragmatic irritation)

jaundice

diarrhoea

pyrexia of unknown origin

ask about foreign travel

Question 7

signs of liver abscess

Answer 7

fever - continuous/spiking

jaundice

tender hepatomegaly, R lobe affected more commonly than L

dullness to percussion and reduced breath sounds at R base of lung from reactive pleural effusion

Question 8

Ix for liver abscess

Answer 8

blood

• FBC - mild anaemai, leukocytosis, increased eosinophils in hydatid disease
• LFT - high alkphos, and BR
• high ESR
• high CRP
• blood cultures
• amoebic and hydatid serology

stool microscopy, cultures - E histolytica or tapeworm eggs

Liver US or CT/MRI- localises structure of mass

CXR

• R pleural effusion/atelectasis
• raised hemidiaphragm

aspiration and culture of abscess material

• most pyogenic liver abscesses are polymicrobial
• .Amoebic abscesses contain ‘anchovy sauce’ fluid of necrotic hepatocytes and trophozoites.