18- Pyogenic liver abscess

Question 1

3 common causes of pyogenic liver abscesses

Answer 1

• post peritonitis
• biliary infection
• arterial hematogenous seeding in systemic infection

Question 2

rf for pyogenic liver abscesses

Answer 2

diabetes mellitus
hepatobiliary (gall stones, malignant obstruction) or pancreatic disease
liver transplant
regular use of proton pump inhibitor
Geographic and host factors

Question 3

what is portal vein pyemia

Answer 3

collection of pus in the portal venous system due to inflammation; this often follows bowel leakage and peritonitis and eventually leads to pyogenic liver abscesses

Question 4

T/F a mnonmicrobial liver abscess due to strep or staph species should cuase investigation for an additional source of infection esp infective endocarditis

Answer 4

T

Question 5

most pyogenic liver abscesses etiologies are

Answer 5

polymicrobial
- mixed enteric facultative and anaerobic species
- E coli and K pneumonia
- Streptococcus milleri group (including S. anginosus,
S. constellatus, and S. intermedius) is an important
cause of liver abscess. When implicated, it should prompt a search for
simultaneous metastatic infections at other locations
• Staphylococcus aureus, Streptococcus pyogenes, and other gram-positive
cocci are recognized pathogens in specific circumstances; in a report of liver abscesses in patients who underwent transarterial
embolization for hepatocellular carcinoma, they accounted for 60 percent of
pathogens

Question 6

manifestation of pyogenic liver abscess

Answer 6

fever, abdominal pain

Question 7

does the absence of right upper quadrant pain exclude liver abscess

Answer 7

no

1/2 of pts with abscess have hepatomegaly, RUQ tenderness or jaundice

Question 8

dx of pyogenic liver abscess

Answer 8

US
CT
MRI

Question 9

primary ddx for liver abscess on imaging is

Answer 9

amebic liver abscess due to E histolytica
NOTE you cant tell pyogenic from amebic with imaging only
- Not so common is Tuberculous abscesses which manifest as multiple small abscesses (military TB)
- Echinococcus hyatid cysts can be differentiated by imaging and serology
- Candida: microabscesses occur in hematologic malignancy during recovery of neutrophic count
- Bartonella, fasciola and endemic fungal infections are small and nodular

Question 10

tx of pyogenic liver abscess

Answer 10

drainage (with CT guide, or US; open surgical - if you need to perform sugery too, laparoscopic, ERCP - useful for pts who previously had biliary procedures ) - the approach to abscess drainage depends on size and number of abscesses and antibiotic therapy (covering streptococci, enteric gram negative bacilli, anaerobes)- 3+ gen cephalosporin, B lactamase inhibitor
Metronidazole to cover E histolytica

Question 11

amebiasis is due to

Answer 11

protozoa entamoeba histolytica

Question 12

most infection of E histolytica are asymtpmatic

Answer 12

True, common manifestations are amebic dysentry and extraintestinal disease (amebic liver abscesses, pulmonary, cardiac, brain)
Amebic liver abscess is the most common
extraintestinal manifestation of amebiasis
Amebae establish hepatic infection by
ascending the portal venous system

Question 13

clincal of pts with amebic liver abscess

Answer 13

• 1-2 weeks of right upper quadrant pain
• cough, sweating, malaise, weight loss, anorexia
• 50% have hepatosplenomegaly

Question 14

tx for amebic liver abscesses

Answer 14

Uses a tissue agents and a luminal agent.
Tissue agents: metronidazole or tinidazole
Luminal agents: it is used to eliminate intraluminal cysts even with stool microscopy for amebic liver abscesses is negative (eg paromomycin, diiodohydroxyquin, diloxanide)

Question 15

hydatid cyst disease is caused by

Answer 15

echinococcus tapeworm (metacestode)

• E granulosus (worldwide- grazing areas), E multilocularis (northern hemisphere)
• E vogeli E oligarthus (central and south america)

Question 16

echinococcus granulosus infection sx

Answer 16

• primary phase is always asymptomatic
• infections are acquired in childhood but do
  not cause clinical manifestations until adulthood
  latent period can last 50 years

Question 17

clinical presentation of E granulosis infection depends on

Answer 17

the site of the cysts and their size (small calcified cysts can remain asymptomatic. But symptoms due to mass effect can also occus)
- cysts grow at 1-5 cm/year

Question 18

hyatid cysts are only in the liver

Answer 18

false
E. granulosus infection of the liver frequently
produces no symptoms.
The right lobe is affected in 60 to 85 percent of
cases.
Significant symptoms are unusual before the
cyst has reached at least 10 cm in diameter.
If the cysts become large, hepatomegaly with or
without associated right upper quadrant pain,
nausea, and vomiting can result.

Question 19

e multilocularis is usually (sx or not?)

Answer 19

symptomatic, non specific

if left untreated 90% of pts will die in 10 years

Question 20

dx of hyatid cysts

Answer 20

imaging and serology

Question 21

T/F serology for E multilocularis is more sensitive and specific than for E granulosis

Answer 21

T

Question 22

gharbi US classification

Answer 22

stage 1: homogeneously hypoechogenic cystic
thin-walled lesion
– stage 2: septated cystic lesion
– stage 3: cystic lesion with daughter lesions
– stage 4: pseudo-tumor lesion
– stage 5: calcified or partially calcified lesion
(inactive cyst)

Question 23

tx options for hydatid cysts

Answer 23

• surgical excision
• PAIR (puncture, aspiration, injection, reaspiration)
• chemotx with anti helminthic agent
• watch and wait for inactive and silent cyst

Question 24

The most common types of visceral abscesses (abscess within an intra-abdominal organ) are

Answer 24

pyogenic liver abscesses

Question 25

T/F Some , abscesses arise from surgical or penetrating wounds,
including injury from migration of an ingested foreign body

Answer 25

T

Question 26

Complications of pyogenic liver abscesses

Answer 26

Abscess rupture (rare; RF for rupture are diameter >6cm with cirrhosis- most ruptures are perihepatic or pleural)

Question 27

RF for mortality in amebic abscesses

Answer 27

• bilirubin >3.5
• albumin <2
• large volume of abscess cavity
• multiple abscesses
• encephalopathy

Question 28

RF for developing pulmonary amebiasis

Answer 28

malnutrition
chronic alcoholism
atrial septal defect (L to R shunt)

Question 29

most common symptoms of pulmonary cystic echinococcus

Answer 29

cough, chest pain, dyspnea

- Majority are asymptomatic in teens despite size

Question 30

Principle manifestations of cyst rupture

Answer 30

fever and acute hypersensitivity reactions (anaphylaxis)