Most of the standard text books stress that as against pyogenic liver abscesses , which are always multiple, amoebic liver abscess is usually single.

Material and Methods

CT Scan was done on 12 patients on whom isotope liver scan was first ordered. Out of cases having one abscess on isotope scan, cases had small multiple abscesses (less than 2 cm in diameter) in addition to the single large abscess seen on isotope scan (Fig. 1). In the other three cases having two abscesses seen on isotope scan, all three extra one to three small abscesses seen on CT Scan (Fig. 2).

CT Scan ordered in four cases with diagnosis made elsewhere of "amoebic hepatitis", showed a single abscess in one case and multiple liver abscesses in the other three.

Discussion

In 1979 and earlier, I wrote that multiple amoebic liver abscesses are more common than a single abscess. [1] But this finding was based on my autopsy experience. At that time the only imaging available was isotope liver scan. Because of a number of fallacies of this scan, often the second abscess or abscesses were missed.

With the availability of single photon emission computed tomography (SPECT) wherein the gamma camera rotates 360° around the patient and the computer gives cross-sectional images like x-ray CT, the yield of information has significantly improved, especially for liver lesions in depth.

Since CT Scanning at present is the most accurate imaging, based on the experience of this imaging, I have now confirmed that amoebic liver abscess is more often multiple. Sonography may not be as accurate in academic classification of multiple amoebic liver abscesses.

Earlier my impression was that multiple small amoebic liver abscesses (Fig. 3) always carried a very bad prognosis. I had observed that these occurred in serious patients having acute amoebic dysentery symptoms and most of these patients died of amoebic peritonitis. At that time, I had observed that these occurred in serious pa -abscesses (Fig. 4) or having one large and multiple small liver abscesses had a good prognosis. While patients with large multiple liver abscesses (Fig. 5) had better prognosis than multiple small amoebic liver abscesses.

My impressions have changed since the new imaging procedure of CT Scan has been available in Bombay. Multiple amoebic liver abscesses are quite common in a patient who has no acute attack of bloody dysentery and who is not toxic or serious. In fact, such patients are in very good health and are often diagnosed as "Amoebic Hepatitis", because of paucity of physical signs and symptoms.

In conclusion multiple amoebic liver abscesses can be divided into two subtypes. The ones which are present in a toxic patient having a severe attack of acute bloody dysentery and where these are often fatal. While the other type are benign and invariably the patient recovers with only antiamoebic drugs. These patients are often labeled as suffering from "Amoebic Hepatitis" or a single liver abscess.

References

1. . KAPOOR 0. P., Amoebic Liver Abscess. S. S. Publishers, Bombay Page 155, 1979.