Nelsons Chapter 386 - Liver Abscess

Question 1

Liver abscess have 1 of 2 infectious etiologies?

Answer 1

1. Pyogenic - involving bacteria

2. Parasitic - amebiasis, ascariasis, toxocariasis

Question 2

Pyogenic liver abscess are uncommon in children but reported in all ages
How bacteria can invade the liver?

Answer 2

Hematogenously through:

1. Hepatic artery
2. Biliary tract
3. Portal vein
4. By contiguous infection

Question 3

Pyogenic liver abscess of Uknown source are classified as?

Answer 3

• crypto genie

Question 4

Children with increased risk of liver abscess?

Answer 4

Children with:

• chronic granulomatous dse (CGD)
• hyper-immunoglobulin E (hyper-IgE) syndrome
• malignancies

Question 5

Clinical sx/s of pyogenic liver abscess?

Answer 5

Nonspecific

• fever
• child
• malaise
• fatigue
• nausea
• abdominal pain (w/ or w/o RUQ tenderness)
• hepatomegaly
• jaundice is uncommon

Question 6

Lab findings for pyogenic liver abscess?

Answer 6

• elevated inflammatory markers
• hypoalbuminemia
• elevated hepatic functioning test
• leukocytosis
• UTZ or
• CT scan
• CXR
  Elevation of the right hemidiaphragm with right pleural effusion
• solitary lesions of right hepatic lobe most common
  Solitary abscess can appear in any hepatic lobe or as multiple disseminated lesions (disseminated candidiasis, bartonellosis, rarely brucellosis)
• culture

Question 7

Culture of pyogenic liver abscess often yield mixed pop’n

Answer 7

• staphylococcus aureus
• streptococcus spp.
• enteric gram negative organisms
  (Escherichia coli, Klebsiella pneumoniae, serratia)
• anaerobic organisms

Question 8

Treatment for pyogenic liver abscess?

Answer 8

broad spectrum empiric antimicrobial treatment
- piperacillin-tazobactam
- ampicillin - sulbatam or
- metronidazole + 3rd gen cephalosporin
- vancomycin
Maybe added to cover methicillin resistant S. aureus
- therapy can be modified based on culture sensitivities

Question 9

Treatment duration of pyogenic liver abscess?

Answer 9

• not standardized
• based on:
  resolution of fever,
  clinical, and
  inflammatory marker improvement
  serial UTZ monitoring
• 4 to 6 wks therapy
  First 2wks parentally

Question 10

Depending on the size and extent of the lesions ___________ may be added to obtain samples for cultures and to shorten illness duration.

Answer 10

• percutaneous or surgical drainage
• percutaneous options include single-pass needle or catheter aspiration or insertion of a continuously draining catheter
• percutaneous drainage should be attempted first for large lesions (> = 5-7cm in dm)
• for smaller lesions initial approach is antibiotic therapy.
  Resolution is monitored by trending inflammatory markers and/or serial imaging

Question 11

• most common extraintestinal manifestation of Entamoeba histolytica infection
• more common in endemic areas
• presentation can be delayed by months to year
• more common among adults 18-55yo
• male predominant

Answer 11

Amebic Liver Abscess (ALA)

Question 12

Pathophysio of ALA?

Answer 12

• amoebic trophozoites invade colonic mucosa -> reach liver through the portal circulation.

Question 13

CM of ALA

Answer 13

• fever
• right upper quadrant pain
• anorexia
• weight loss
• may not have an associated colitis

Question 14

Lab findings in ALA

Answer 14

• leukocytosis with eosinophilia
• inc. alk phos.
• UTZ or CT -> abscess
• confirmed by serum ELISA
• most specific and sensitive: stool assays PCR > stool antigen detection > microscopy (least sensitive cause cant easily distinguish E dispar, E. moshkovskii)

Question 15

Tx of ALA

Answer 15

- nitroimidazole / metronidazole 
    7-10days 
    To kill trophozoites 
Followed by
- paromomycin 
    7days 
    Luminal agent
    To kill colonic cyst  
- for large abscess (>= 5-7cm in dm) my benefit from percutaneous aspiration in addition to medical therapy.