Amoebic liver abscess

Amebic liver abscess: Clinico-radiological findings and interventional management

In its classic form, amebic liver abscess (ALA) is a mild disease, which responds dramatically to antibiotics and rarely requires drainage. However, the two other forms of the disease, i.e., acute aggressive and chronic indolent usually require drainage. These forms of ALA are frequently reported in endemic areas. The acute aggressive disease is particularly associated with serious complications, such as ruptures, secondary infections, and biliary communications. Laboratory parameters are deranged, with signs of organ failure often present. This form of disease is also associated with a high mortality rate, and early drainage is often required to control the disease severity. In the chronic form, the disease is characterized by low-grade symptoms, mainly pain in the right upper quadrant. Ultrasound and computed tomography (CT) play an important role not only in the diagnosis but also in the assessment of disease severity and identification of the associated complications. Recently, it has been shown that CT imaging morphology can be classified into three patterns, which seem to correlate with the clinical subtypes. Each pattern depicts its own set of distinctive imaging features. In this review, we briefly outline the clinical and imaging features of the three distinct forms of ALA, and discuss the role of percutaneous drainage in the management of ALA.

Amoebic liver abscess: presentation and complications

BACKGROUND

Amoebic liver abscess (ALA) is the most common inflammatory space occupying lesion of the liver. It has a highly variable presentation causing diagnostic difficulties. Untreated, complicated ALA has high morbidity and mortality.

OBJECTIVE

To study the various types of clinical presentation and complications of ALA in order to establish early diagnosis and prevent complications.

MATERIALS AND METHODS

A prospective study was conducted in the Department of Surgery of Calcutta National Medical College and Hospital from July 2005 to June 2008. All patients with a confirmed diagnosis of ALA during this period were included in the study.

RESULTS

Seventy-two patients with 76 ALAs were studied over a 3-year period. The age ranged from 21 to 72 years (mean age being 43.64 years). There were 66 males (91.67% of the patients) and 6 females (8.33% of the patients). The (31-40 years) age group showed the highest incidence consisting of 40.28% of the cases. Pain was located most commonly in the right hypochondrium in 60 patients (83.33%). Fever was observed in 58 patients (80.56%). Solitary abscess cavity was present in 68 patients (94.44%). The right lobe alone accounted for 65 (85.53%) of the abscesses. The most common echo pattern encountered in ultrasonography was the echorich pattern in 54 (71.05%) abscesses. Forty-four patients (61.11%) gave history of alcohol consumption. Diagnosis was missed in 21 patients (29.17%), particularly in those with atypical presentations. The most common complication was pleuropulmonary in 24 patients (33.33%), followed by intraperitoneal rupture in 19 patients (26.39%). Other complications were jaundice (n = 11), ascites (n = 9), subhepatic effusion (n = 7), subphrenic abscess (n = 3) and intrapleural rupture (n = 2). Ultrasonography was useful in diagnosing ALA. Despite successful therapy 23 patients (31.94%) had residual abscess cavities on ultrasonography even after 6 months.

CONCLUSION

In an endemic area a patient presenting with lower chest or upper abdominal pain along with tender hepatomegaly should raise the suspicion of ALA. Sonography remains an important tool in the diagnosis of ALA.

Amoebic liver abscess in pregnancy

We describe the case of an amoebic liver abscess (ALA) presenting in the third trimester of pregnancy which raised both diagnostic and treatment dilemmas as well as being associated with preterm labour. Amoebic liver abscess is caused by the protozoan organism Entamoeba histolytica which is endemic in many parts of the developing world. Invasion of the colonic mucosa results in the clinical syndrome of amoebic dysentery and in some cases dissemination to the liver or other organs occurs resulting in abscess formation. Amoebic liver abscess is a rare complication of pregnancy and there are few reports in the world literature, these being mostly from endemic areas. We present here the case of a caucasian female who presented with an amoebic liver abscess in the third trimester of pregnancy, thirteen months after returning to Australia from a short holiday in Bali.

Amebic liver abscess: spare the knife but save the child

BACKGROUND/PURPOSE

Amebic liver abscess (ALA), the most common extraintestinal manifestation of infection with Entameba histolytica, carries significant morbidity and mortality in the pediatric age group. The efficacy of metronidazole in the treatment of ALA is well established, but the role of surgical intervention remains controversial. Many investigators still advocate aggressive surgical therapy for complicated and ruptured ALA. Reports regarding management of ALA in children are sparse and deal with small numbers of patients. The objective of this study was to assess the effectiveness of parenteral metronidazole combined with judicious aspiration of ALA in obviating the need for surgical intervention.

METHODS

The medical records of all children admitted with the diagnosis of ALA between 1986 and 1997 to the Aga Khan University Hospital were reviewed retrospectively. The diagnosis of ALA was confirmed in 48 patients by an ultrasound scan together with elevated indirect hemagglutination (IHA) titres (>250). Ages ranged from 3 weeks to 14.5 years.

RESULTS

Thirty-seven (75%) children were below the fifth percentile for height and weight, and 45 (93.7%) presented with a hemoglobin level of less than 10.0 g/dL. Comorbid factors included pulmonary tuberculosis (n = 2, chicken pox (n = 1), tetralogy of Fallot (n = 1), and thalassemia major (n = 2). There was a mean delay of 13 days before presentation to the hospital. All patients were treated with parenteral metronidazole and broad-spectrum antibiotics. The latter were discontinued on confirmation of the diagnosis. The duration of treatment with metronidazole ranged from 2 to 5 weeks. Percutaneous aspiration of the ALA was performed under ultrasound guidance using sedation in 28 patients for one or more of the following indications; ALA greater than 7.0 cms (n = 20), left lobe involvement (n = 8), and no response after 48 hours of medical therapy (n = 6). Nine patients required more than one aspiration. One patient with peritoneal rupture of the ALA additionally underwent percutaneous aspiration of the peritoneal cavity under ultrasound guidance. One patient required insertion of a chest tube after rupture of the ALA into the right pleural cavity, and another underwent urgent bronchoscopy after rupture of the abscess into the tracheobronchial tree. The hepatobronchial fistula closed spontaneously with medical therapy. No patient required open surgical drainage, and all recovered without relapse. The mean duration of hospitalization was 12 days.

CONCLUSION

Our experience suggests that parenteral metronidazole combined with timely aspiration of the abscess can obviate the need for surgical intervention in large and complicated ALA even in malnourished children who present late for treatment.

Conservative initial treatment for liver abscesses in children

A total of 124 children aged less than 14 years with a liver abscess were seen in a 16-year period (1974-1990) and treated by non-operative initial management. Of the abscesses 98 occurred in the right liver and 26 in the left. The abscesses were solitary in 93 patients. Overall, 77 of the solitary and 21 of the multiple abscesses were confined to the right liver. In 78 of the right-sided and 20 of the left-sided abscesses the infection was primarily pyogenic in nature with Staphylococcus aureus being the usual organism cultured. The remainder were of amoebic origin. Clinical features were similar in patients with amoebic and pyogenic abscesses. Clinical and ultrasonographic follow-up demonstrated successful non-operative management and healing in 37 per cent of all patients submitted to an initial protocol of medical supportive care and antibiotic therapy. Of the multiple abscesses 60 per cent responded to non-operative management. Fourteen of the 16 solitary left-sided liver abscesses required drainage and three left-sided abscesses ruptured before drainage. Patients with a solitary left-sided abscess warrant early operative intervention.