Echinococcus of the liver.

There are two forms of echinococcus that affect the liver of humans, E granulosus and E multilocularis. The second is comparatively rare and geographically isolated. Differentiation between the two is important and easy using specific serological tests. Treatment and prognosis differ considerably; E granulosus is comparatively simple to treat and death is exceptional, whereas E multilocularis is often inoperable and death has until recently been common in all but early disease although chemotherapy is now changing the outcome. The clinical presentations of both forms of hydatid disease are comparatively nonspecific. The past 10 years have seen considerable changes in the treatment of hydatid disease. The introduction of mebendazole, albendazole, and praziquantell-3 has improved treatment. What now are the relative places of surgery and chemotherapy? Patients with genuinely inoperable disease and those who are unfit for surgery should clearly receive medical treatment while the young and fit with symptomatic, easily removable cysts should have surgery but adjuvant chemotherapy may reduce the risks of recurrence.4 5 The treatment of asymptomatic cysts is less clear. For large cysts, surgery should be favoured but many patients can now be successfully treated medically. The treatment of patients who do not fall into these extremes is less clear. Most patients probably remain best served by an operation but with both pre and postoperative chemotherapy.