Liver%20abscess Treatment
Principles of Therapy
Principles of Empiric Antibiotic Therapy
- Antibiotics should be started as soon as pyogenic liver abscess is considered
- Antibiotic therapy alone w/o drainage should be considered only in patients w/ small abscesses (<3-5 cm) that are not amenable to drainage & in those in whom drainage will pose an unreasonable risk
- Initial antibiotics should be broad spectrum to cover common causative pathogens of pyogenic liver abscess
- Metronidazole should be part of the initial therapy to provide empiric treatment for both anaerobes & E histolytica
- Antibiotics should be based on local antimicrobial resistance patterns & modified based on culture & sensitivity testing results
Pharmacotherapy
Antibiotic Options
- Ampicillin + Aminoglycoside
- Should be part of antibiotic regimen when a biliary source is suspected
- Cephalosporins
- 2nd or 3rd generation cephalosporins are recommended when a colonic source is considered
- Provide excellent coverage for enteric bacilli
- Some cephalosporins have coverage against anaerobes
- Metronidazole or Clindamycin
- Should be included in antibiotic regimen to cover for anaerobes if other antibiotics being used do not have anaerobic coverage
- If amoebiasis is suspected, Metronidazole should be started
- Other antibiotics/antibiotic combinations that may be used for pyogenic liver abscesses include:
- Antipseudomonal penicillins w/ or w/o beta-lactamase inhibitor
- Carbapenems
- Recommended for patients w/ diabetes mellitus (DM) due to risk of extended-spectrum beta-lactamase (ESBL) infection
- Fluoroquinolone + Metronidazole +/- aminoglycoside
- Vancomycin + Metronidazole +/- aminoglycoside
Drugs for Amoebic Liver Abscess
- Chloroquine
- May be used as an adjunct w/ Metronidazole in patients w/ large & multiple abscesses
- Active against E histolytica trophozoites, achieves high concentrations in hepatic tissue
- Metronidazole
- Highly lethal to E histolytica trophozoites
- Absorbed quickly through the gut w/ excellent bioavailability
- Secnidazole, Tinidazole
- May be substituted for Metronidazole in uncomplicated cases of invasive amoebiasis
- Luminal amoebicides eg Diloxanide furoate, Etofamide, Iodoquinol, Nitazoxanide & Paromomycin are active against E histolytica cysts & trophozoites in the intestine
Duration of Antibiotic Therapy
Pyogenic Liver Abscess
- Duration of therapy should be based on severity of infection & patient’s response
- Intravenous (IV) antibiotics should be continued for at least 2 weeks; therapy may be continued through the oral route afterwards for up to 6 weeks
- Multiple abscesses may need up to 12 weeks of antibiotic treatment
Amoebic Abscess
- Intravenous (IV) Metronidazole should be given for 5-10 days
- Following a course of Metronidazole, an oral luminal amoebicide should be given for 7 days to eradicate residual amoeba in the intestines
Non-Pharmacological Therapy
Indications for Drainage
- Most pyogenic abscesses require drainage
- If multiple abscesses are present, only the largest abscess may require aspiration
- Dispensing w/ a drainage procedure (ie giving antibiotics alone) should be considered only in patients w/ small abscesses not amenable to drainage or in those for whom drainage is too risky
- Patients w/ amoebic abscesses require drainage only for very large lesions & for those in whom rupture is imminent
Percutaneous Needle Aspiration
- Done under computed tomography (CT) scan or ultrasound guidance; often the initial diagnostic procedure performed for a single abscess ≤5 cm
- Requires only local anesthesia & minimal sedation
- Allows sampling of small &/or multiple lesions for culture; may do away w/ the need for catheter placement
Percutaneous Catheter Drainage
- Standard of care for most liver abscesses
- Entails placement of a catheter under ultrasound or computed tomography (CT) scan guidance followed by daily flushing
- Should be the initial intervention for small abscesses <5 cm & for single abscess >5 cm
- May be used for draining multiple abscesses
- Advantages: Does not require general anesthesia, allows gradual drainage, faster recovery rate
- Contraindications: Complicated thick-walled abscess w/ viscous pus, peritonitis, complicated access
Surgical Drainage
- Indications for surgical drainage: Treatment of underlying intra-abdominal disorders including peritonitis, failure of previous percutaneous catheter drainage, multiple & loculated abscesses, ruptured abscess, viscous abscess obstructing the drain, large abscesses >5 cm
- Open drainage may be through the transperitoneal or transpleural approach
- Laparoscopic drainage enables exploration of entire abdomen w/ significantly reduced patient morbidity
- Possible complications of drainage include recurrent pyogenic hepatic abscess, intra-abdominal abscess, kidney or liver failure, surgical wound infection
Endoscopic Retrograde Cholangiopancreatography (ERCP)
- May be used in patients w/ prior biliary procedures & whose infection is connected w/ the biliary tree