Colonic involvement in amebic liver abscess: does site matter?

BACKGROUND Colonic involvement in amebic liver abscess (ALA) occurs in more than half of the patients. However no studies have found any association between the site of the colonic lesions and location of abscesses in the liver. Thus, the present study was designed to find the correlation between colonic involvement in solitary and multiple ALAs. METHODS This is a case control study of 80 patients allocated in two groups, the first with solitary (controls) and the second with multiple ALAs (cases). Colonoscopy was performed in all patients enrolled in the study. RESULTS Solitary ALA was seen in 70% of patients whereas multiple ALAs in 30%. Colonic involvement in the form of erythema, inflammation and ulceration was seen in 77.5% of cases of ALA. 71.4 % cases of solitary ALA had colonic lesions compared to 91.6% cases of multiple ALAs (P=0.02). Most of the patients with multiple ALAs had involvement of the transverse and right colon (75%). Involvement of right colon was present in all patients with colonic involvement. A significant involvement of the right and transverse colon was seen in cases of multiple compared to solitary ALA (P<0.0001). CONCLUSION Colonic involvement is present in more than two thirds of patients with ALA. When colonic involvement is present, right colon lesion is universally present. Colonic involvement may extend beyond hepatic flexure in patients with multiple amebic ALAs, either involving right hepatic lobe or both lobes.