Pyogenic Liver abscess (PLA)
Discuss the symptoms and signs of liver abscess?
- Symptoms- Fever, abdominal pain, nausea and vomiting, chest symptoms (cough, chest pain), weight loss, anorexia,
- Signs- abdominal tenderness, hepatomegaly, chest signs like consolidation, jaundice
Discuss the investigations for liver abscess?
- Abnormal LFTs- raised alkaline phosphatase in majority. Transaminases and bilirubin may be raised too
- CT scan or Ultrasound is used to diagnose PLA. Imaging cannot distinguish amoebic from pyogenic liver abscess
- Gram stain and cultures (both aerobic and anaerobic) of the aspirate
- Blood cultures should be done in all as a significant number are positive in PLA
What are the causes of liver abscess?
- Biliary source of sepsis from gallstones, biliary stricture, ERCP and operation is the commonest cause
- Portal pyaemia from diverticular disease, Crohn’s disease, colon cancer, appendix abscess
- Haematogenous spread of infection
- Cryptogenic- no cause found
Discuss the microbiology of PLA?
Mostly poly microbial with both aerobes and anaerobes
Gram negative bacilli and streptococcus milleri group are important causes
Discuss the management of PLA?
Systemic antibiotics are the mainstay of treatment. Ciprofloxacin plus metronidazole or augmentin (amoxicillin-clavulanate) may be used as the initial empiric treatment. The antibiotics are initially used IV. The regime should be changed based on the culture and sensitivity results. In the absence of drainage, antibiotics are given for 4-6 weeks. As usual the duration of therapy is guided by the clinical response and use of white cell count, CRP etc. In patients who have had drainage, the duration of therapy can be reduced to 2-4 weeks
Drainage- Large pyogenic abscesses (5 cms or more) usually need drainage, in addition to antibiotics for effective resolution. Drainage may also be needed in patients with poor response to antibiotics alone
There are currently two methods for drainage, namely:
Ultrasound or CT guided percutaneous drainage- a catheter is placed in the abscess cavity and left in place until drainage is minimal (5-7 days)
Surgical- open or laparoscopic drainage- may be required if there is inadequate response to percutaneous drainage. Surgical drainage may also be preferred if there is an underlying disease requiring primary surgical management. Surgical drainage may also be considered if there are multiple abscesses or if the abscesses are loculated
Discuss the role of large bowel investigations in PLA?
A barium enema or colonoscopy is usually done to locate a source of infection in PLA unless a biliary or other source is apparent.
