What are the two etiologies of a LIVER ABSCESS?
1. Pyogenic liver abscess: most common cause is biliary tract obstruction - obstruction of bile flow allows baterial proliferation. Other causes include GI infection (diverticulitis, appendicitis) with spread by the portal veonous system and penetating liver trauma (GUNSHOT WOUND, SURGERY)
-causative organisms: E. coli, klebsiella, proteus, eneterococcus, anaerobes
-features: fever, malaise, anorexia, weight loss, nausea, comiting, RUQ pain, jaundice.
diagnosis by US or CT scan: elevated LFTs
-treatment: FATAL if untreated *treatment with IVAB and percutaneous drainage of the abscess. which reduces the mortality to about 5-20%. Surgical drainage is sometimes considered
2. Amebic liver abscess: most common in men (9:1); homosexual. Fecal oral contact transmission. Caused by intestinal amebiasis (e. histolytica) - the amebae reach the liver via the hepatic portal vein.
-clinical features: fever, RUQ pain, n/v, hepatosplenomegay, diarrhea
-seriological testing (immunoglobulin G enzyme immunoassay) will estbolish diagnosis. Elevated LFTs; E. histolytica stool antigen test *detects protozoe in the stool). Imagine studies (US/CT) identifies the abscess but it is difficult to distinguish from a pyogenic abscess.
-IV metronidazole is effective treatment in most cases. Therapeutic aspiration of the abscesss (IMAGE_GUIDED percutaneous aspiratoin causses. Therapeutic aspiration of the abscess may be necessary if the abscess is larger (HIGH RISK OF RUPTURE) or if there is no response to medical therapy