The management of hepatic abscess

Dr Miruna David Consultant Microbiologist and Clinical Service Lead University Hospitals Birmingham Epidemiology

• Amoebic – nearly exclusively in travellers and people born abroad • – Rare disease – Peak incidence in fifth and sixth decades of life Epidemiology

• Amoebic liver abscess – nearly exclusively in travellers and people born abroad • Pyogenic liver abscess – Rare disease – Peak incidence in fifth and sixth decades of life Pathogenesis

1. Direct spread from biliary infection. Underlying disease (eg. or malignant obstruction ) in 40 -60 % of cases 2. Haematogenous seeding from the systemic circulation (especially if monomicrobial and due to a streptococcal or staphylococcal species) 3. Portal vein pyemia, usually related to bowel leakage and 4. Via contiguous route - from surgical or penetrating wounds, including injury from migration of an ingested foreign body • most commonly involve the right lobe of the liver ( is larger and has greater blood supply than the left and caudate lobes) • may be accompanied by pylephlebitis (infective suppurative thrombosis of the portal vein) Aetiology (1)

• Bacteria (‘Pyogenic liver abscess’) – Gram negative • “coliforms”: E. coli, K. pneumoniae is an important emerging cause of primary liver abscess, most commonly in Asia (pyogenic liver abscess PLA syndrome). • Burkholderia pseudomallei (the agent of melioidosis) should be considered in patients from endemic areas (especially SE Asia and Northern Australia). – Gram positive: • Streptococcus milleri group (including S. anginosus, S. constellatus, and S. intermedius) • Staphylococcus aureus, Streptococcus pyogenes, and other gram- positive cocci (in specific circumstances ) – Anaerobes (Bacteroides, Fusobacterium, Clostridium) Aetiology (2)

• Tuberculous liver abscesses are uncommon but should be considered when typical pyogenic organisms are not recovered from cultures • Fungi (Candida sp.) – Hepatosplenic candidiasis in patients who have received chemotherapy and presents during recovery of counts following a neutropenic episode. – Neonates • Parasites – histolytica – especially in primary liver abscess, especially in patients who are from or have travelled to an endemic area within the past 6 months – Echinococccus granulosus (hydatid ) Diagnosis

A. Clinical features B. Imaging studies C. Microbiological cultures Clinical manifestations

• - in approx. 90 % of patients • Abdominal (right upper quadrant) pain and/or tenderness in 50 – 75 % patients • Hepatomegaly • Jaundice • , vomiting, anorexia, weight loss and malaise

• Abscess rupture – rare complication – perihepatic or into the pleural space – risk factors for rupture: abscess diameter >6 cm and coexisting Microbiology diagnosis

• Blood cultures are essential; positive in up to 50 % of cases • CT or ultrasound-guided aspiration - Gram stain and culture (both aerobic and anaerobic). • Culture-independent diagnosis • Amoebic ( very good sensitivity and specificity) Management

Drainage and Antibiotics Management - Drainage

• Drainage techniques – CT-guided or US-guided percutaneous aspiration/drainage (+/- catheter placement) – surgical drainage – drainage by ERCP • Drainage catheters should remain in place until drainage is minimal (usually 5-7 days). • If percutaneous needle aspiration (without catheter placement), repeat aspiration may be required in up to one-half of cases Antibiotics

• No randomized controlled trials • Based upon the probable source of infection and should be guided by local bacterial resistance patterns • Empirical broad-spectrum iv antibiotics need to be started as soon as blood cultures taken, to cover both Gram negative and anaerobic organisms • Targeted - if cultures positive • Can de-escalate to oral if improving Antibiotics

• Βeta-lactam/ beta-lactamase inhibitor combinations – Co-amoxiclav iv 1.2g TDS – Piperacillin-tazobactam 4.5g TDS • Fluoroquinolones (eg. ciprofloxacin ) and (in penicillin allergy or as an iv to oral switch) • Carbapenems (meropenem 1g TDS - in patients colonised with ESBL-producing organisms) Antibiotic therapy duration

• No randomized controlled trials evaluating the optimal duration of therapy. • 4-6 weeks total course , out of which first 2-3 weeks iv • determined by the extent of infection and the patient's clinical response to initial management. Patients with abscess(es) that are difficult to drain usually require longer courses of therapy. • Monitor clinical indicators :pain, temperature, WBC and CRP. • Follow-up imaging should only be performed in the setting of persistent clinical symptoms or if drainage is not proceeding as expected; radiological abnormalities resolve much more slowly than clinical and biochemical markers. Liver abscess in transplantation

• Often associated with hepatic artery thrombosis (HAT) • May require re-transplantation • Often due to multi-resistant organisms (ESBL, VRE, multi-resistant Pseudomonas) • Duration of treatment longer • Look out for drug interactions Antifungals for candida

Seek expert advice Depends on isolate and drug inetrcations • Fluconazole • Amphotericin B (Ambisome) • Echinocandins

Treatment of amoebic liver abscess (ALA) • Almost always can be treated with medical therapy alone • Metronidazole 750mg TDS for 7-10 days Or 2g od for 3 days PLUS • 10mg/kg PO TDS for 7 days (intraluminal agent to eradicate gut carriage and prevent relapse) THANK YOU