LIVER ABSCESSES
Two categories of liver abscess have been identified: amebic
and pyogenic. Amebic liver abscesses are most commonly
caused by Entamoeba histolytica. Most amebic liver abscesses
occur in the developing countries of the tropics and sub-
tropics because of poor sanitation and hygiene. Pyogenic
liver abscesses are much less common, but they are more
common in developed countries than the amebic type.
Pathophysiology
Whenever an infection develops anywhere along the biliary
or GI tract, infecting organisms may reach the liver through
the biliary system, portal venous system, or hepatic arterial
or lymphatic system. Most bacteria are destroyed promptly,
but occasionally some gain a foothold. The bacterial toxins
destroy the neighboring liver cells, and the resulting necrotic
tissue serves as a protective wall for the organisms.Meanwhile,
leukocytes migrate into the infected area.The result is an
abscess cavity full of a liquid containing living and dead
leukocytes, liquefied liver cells, and bacteria.Pyogenic
abscesses of this type may be either single or multiple and
small. Examples of causes of pyogenic liver abscess include
cholangitis (usually related to benign or malignant obstruction
of the biliary tree) and abdominal trauma.
Clinical Manifestations
The clinical picture is one of sepsis with few or no localizing
signs. Fever with chills and diaphoresis, malaise, anorexia,
Two categories of liver abscess have been identified: amebic
and pyogenic. Amebic liver abscesses are most commonly
caused by Entamoeba histolytica. Most amebic liver abscesses
occur in the developing countries of the tropics and sub-
tropics because of poor sanitation and hygiene. Pyogenic
liver abscesses are much less common, but they are more
common in developed countries than the amebic type.
Pathophysiology
Whenever an infection develops anywhere along the biliary
or GI tract, infecting organisms may reach the liver through
the biliary system, portal venous system, or hepatic arterial
or lymphatic system. Most bacteria are destroyed promptly,
but occasionally some gain a foothold. The bacterial toxins
destroy the neighboring liver cells, and the resulting necrotic
tissue serves as a protective wall for the organisms.Meanwhile,
leukocytes migrate into the infected area.The result is an
abscess cavity full of a liquid containing living and dead
leukocytes, liquefied liver cells, and bacteria.Pyogenic
abscesses of this type may be either single or multiple and
small. Examples of causes of pyogenic liver abscess include
cholangitis (usually related to benign or malignant obstruction
of the biliary tree) and abdominal trauma.
Clinical Manifestations
The clinical picture is one of sepsis with few or no localizing
signs. Fever with chills and diaphoresis, malaise, anorexia,
