Amebic liver abscess

Opinion statement Amebic liver abscess should be suspected in travelers returning from endemic areas or in immunocompromised patients who present with fever, right upper quadrant pain, hepatomegaly, and a liver lesion on an imaging study. Rapid initiation of therapy without serologic confirmation of infection, if necessary, is important to minimize complications. Metronidazole is given orally or intravenously for 14 days. The drug is generally well tolerated and leads to resolution of symptoms in most patients within 2 to 3 days. It is effective against luminal cysts in only 50% of patients and, therefore, must be followed by a course of treatment with paromomycin (Humatin; Parke-Davis, Morris Plains, NJ) or another luminal antiamebic agent to eradicate the parasite. Image-guided drainage of an amebic liver abscess is indicated in patients who do not respond to antimicrobial therapy or who are at risk of abscess rupture. Surgery is reserved for patients with a ruptured abscess. Although medical therapy is generally successful in the treatment of infection caused by Entamoeba histolytica, the development of potent vaccines will be needed for worldwide eradication of disease attributable to E. histolytica.     

Amebic liver abscess

We report eight cases of amebic liver abscess. All patients were men, and four were homosexual. Five of the eight patients had syphilis, but the four homosexual patients who were tested for HIV infection were negative. Ultrasonography (US), with or without needle aspiration, is the best method for diagnosing amebic liver abscess, and the treatment of choice is US-guided needle aspiration of the abscess followed by metronidazole therapy. Complication by other sexually transmitted diseases is another important factor affecting the treatment of this disease.     

Amebic liver abscess

Amebiasis is a widespread parasitic disease caused by Entamoeba histolytica. This protozoan organism is the third leading parasitic cause of death in the developing world and is an important health risk to travelers in endemic areas. Amebiasis most commonly results in asymptomatic colonization of the gastrointestinal tract, but some patients may develop intestinal invasive disease or extraintestinal disease-amebic liver abscess being the most common extraintestinal manifestation. This article reviews epidemiologic features, pathophysiology, clinical features, diagnostic tests, imaging studies, treatment of amebic liver abscess, and prevention measures.     

Amebic liver abscess

Amebic liver abscess (ALA) highly endemic in most developing tropical countries is being encountered more frequently in other geographical areas maybe secondary to increased travel to areas where the disease is endemic as well as in the homosexual population. We report a classical clinical case of ALA in a 44 years old man diagnosed by ultrasound and positive seroameba titers who responded to oral imidazoles.     

Amebic abscess of the liver

Fifteen patients with amebic abscess of the liver were seen at two California county hospitals over a period of 3 1/2 years. Of the 15 patients, 9 diagnoses were proven and 6 were presumptive. Fourteen of the patients had made a recent trip or had ready access to Mexico. The clinical finding of particular note was the high incidence of right lower lung field abnormalities. Useful laboratory studies included the combination of an elevated BSP, alkaline phosphatase, and direct reacting bilirubin. The value of the liver scan is emphasized. The high incidence of secondary infection of the abscesses is stressed. The uncomplicated postoperative courses of those patients treated by surgical drainage and postoperative chemotherapy for amebiasis is of particular importance since this approach has been considered in the past to be most hazardous.The author is indebted to Robert A. O'Reilly, M.D. for his assistance and helpful suggestions. The indirect hemagglutination tests were performed through the courtesy of Dr. John F. Kessel, School of Public Health, University of California, Los Angeles, Calif.     

Amebic liver abscess: 1966–1976

A 10-year retrospective analysis of 15 patients with amebic liver abscess is reviewed and represents a continuation of the previous 2-decade experience at our institution (37 patients). Records were studied to determine the population affected, presenting symptoms, physical and laboratory findings, type and response to therapy. Most patients were rural males of lower socioeconomic status in the third to fifth decade of life. They presented as a febrile illness with abdominal pain for an average of 2 1/2 months duration. Significant physical abnormalities were tender hepatomegaly (93%), right-sided pulmonary changes (40%), and fever (66%). All patients had abnormal liver scan, positive amebic serology, and hypoalbuminemia. All patients promptly responded to amebicidal therapy except one whose therapy was delayed. Clinical suspicion, liver scanning, serologic testing, and response to therapy are the keys to diagnosis.     

Amebic liver abscess: a therapeutic approach

The clinical presentation of 48 patients with amebic liver abscess was no different than that reported in earlier studies. However, most patients were from countries endemic for parasitic disease. Failure to consider this diagnosis resulted in potentially avoidable surgery for six patients. Although metronidazole was successful primary therapy in 85% of 41 patients so treated, four of seven ruptured abscesses occurred in cases where metronidazole treatment failed. For assessment of factors that might predict metronidazole treatment failures, multiple parameters were analyzed. Of the factors evaluated, only timing of clinical response correlated with successful therapy. Ninety-four percent of metronidazole responders showed dramatic clinical improvement within 72 hours of initiation of therapy, whereas only 33% nonresponders had improved modestly during this time (P = .0014). Therefore, early diagnosis of amebic liver abscess in patients from endemic areas and treatment with metronidazole will result in successful therapy in 85% of cases. Surgical intervention or alternative medical therapy is indicated for those patients who do not respond after 72 hours of metronidazole therapy.     

Amebic liver abscess. Three years experience

BACKGROUND: amebic liver abscess is frequently seen in endemic regions, and has a poor prognosis when diagnosis and treatment are inappropriate. AIM: to evaluate and compare our own results; to propose a new classification and therapeutic algorithm. DESIGN: an observational and retrospective study. METHOD: medical records were reviewed for sex, age, signs and symptoms, images, laboratory tests, size, location, treatment, hospital stay, and morbidity-mortality. RESULTS: sixteen patients with amebic liver abscess had been treated -9 were males, mean age was 30.56 years, all abscesses were solitary, 14 were in the right hepatic lobe, average size was 63.25, and 10 were of the collected type according to N Gbesso s classification. Seven patients had a good response to medical treatment, 6 needed percutaneous drainage, and 3 required surgery. Morbidity was 12.5% and mortality 0%. Average hospital stay was 7.68 days. CONCLUSION: our results are similar to those in other published series. The addition of two new groups to N Gbesso s classification provides better therapeutic orientation. We believe that early percutaneous drainage for collected abscesses bigger than 5 cm may improve symptoms and shorten hospital stay.     

Amebic liver abscess in an elderly AIDS patient

An elderly bisexual male AIDS patient, whose CD4 cell count was 128/mm3 and HIV-RNA was 3.0x10(5) copies/ml, was admitted because of amebic liver abscess and poor nutritional condition. He was treated with daily doses of 1,500 mg of metronidazole for 14 days for amebic liver abscess and with anti-HIV drugs; good therapeutic results were observed. Our study indicates that amebic liver abscess is easily treated by appropriate administration of metronidazole even in an old AIDS patient receiving anti-HIV drugs with low CD4 cell counts and high HIV-RNA values.     

Amebic liver abscess: presentation of 4 cases

We report four patients with amebic liver abscess diagnosed in our hospital between January 1985 and January 1990. Mean patient age was 40 years. All patients had previously travelled to an endemic area. Fever, weight loss, right-upper-quadrant pain and hepatomegaly were the most frequent clinical manifestation. Two patients had a history of diarrhea. Diagnosis was made by epidemiology, clinical manifestation, ultrasonic scanning and computerized tomography and serologic test. Two patients received metronidazole exclusively and two patients required percutaneous catheter drainage under ultrasound guidance.