Amoebic versus pyogenic liver abscess.

OBJECTIVES To study the differences between the clinical presentation and complications of amoebic and pyogenic liver abscess. To correlate the diagnostic significance of Entamoeba Indirect Haemagglutination test (E.IHA) in establishing the diagnosis of amoebic liver abscess. DESIGN Open cohort observational study. SETTING Department of Medicine (Medical Unit II) Jinnah Postgraduate Medical Centre, Karachi. PARTICIPANTS Fifty two patients aged 13-70 years admitted in Medical Unit II and diagnosed to have liver abscess. INTERVENTIONS Group A comprised of patients clinically diagnosed to have amoebic liver abscess and received Metronidazole 500mg iv x 8 hourly for atleast 10 days or more if patient developed complications. Group B comprised of patients diagnosed to have pyogenic abscess and received Cefotaxime 1g iv x 8 hourly for the same duration or more if complicated (antibiotic reviewed in accordance with culture and sensitivity report). MAIN OUTCOME MEASURES Differences in the clinical presentation, complications and diagnostic parameters between the two groups of patients. RESULTS It was not possible to differentiate between amoebic and pyogenic liver abscess on clinical grounds, routine investigations and imaging techniques. Aspiration of pus, especially if the abscess was multiple, was most helpful in differentiating the two types of abscesses. Serological test of E.IHA was highly specific and sensitive for amoebic liver abscess. CONCLUSION Majority of liver abscesses in Karachi are due to Entamoeba Histolytica. Pyogenic abscess though less frequent, must be excluded by pus aspiration and culture and sensitivity. E.IHA is a good rapid method of discriminating between the two types of abscesses.