Amebic liver abscess: spare the knife but save the child

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.

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.

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.

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.