How to manage asymptomatic liver hydatids.

ystic echinococcal disease disappeared many decades ago from industrial countries. Only rarely now, and primarily because of increased international travel, liver hydatids surface as clinical curiosities at medical conferences in western countries. The situation is usually that of a liver hydatid having ruptured into the biliary system causing bile duct obstruction. Invariably the consensus among discussants is that the patient should have been operated upon much earlier to avoid the cyst becoming complicated. Such a verdict, however, is inappropriate and inapplicable in endemic areas of developing countries where echinococcal disease is still rampant. In these regions so many cases of asymptomatic cases of liver hydatids are detected in the course of ultrasound investigation for other conditions, that it would impossible to handle all of them surgically. The fact that many liver hydatids are first encountered as irrgularly calcified and clinically silent lesions, suggests that most liver hydatids undergo a slow process of spontaneous abortion. They can, therefore, be left alone. An equally important reason for a conservative approach to incidentally discovered liver hydatids in endemic areas is an economic one. To manage all asymptomatic liver hydatids prophylactically to avert possible complications, would overwhelm available health resources in endemic areas. To operate on the many, fearing complications in the few, cannot be justified in that setting. Can incidentally discovered asymptomatic liver cysts be treated mediaclly when risk taking, even for the few, is unacceptable? About forty years ago benzimidazole carbamate derivatives, mebendazole first and then albendazole, were reported from Europe to have deleterious effects on the larval stage of the parasite Echinococcus granulosus in man. Mebendazole has been used for many years in India as an effective vermifuge with low absorption rate. Enough experience has accumulated to show that clinical efficacy of these drugs against hydatid cyst is no more than about 50%, even after prolonged administration. Fortunately their toxicity over long periods of time is also very low. 4 It would be reasonable, therefore, to empirically administer these drugs to patients in endemic areas who are accidentally found to have a benign cystic lesion of the liver suspected to be echinococcal. Drug treatment should be continuous and not interrupted, with liver function and the blood picture checked at intervals, and pregnancy avoided in the interim. Both the physician and the patient should fully understand that success is neither guaranteed nor apparent until at least a full year of drug treatment. Involution of the cyst may have been the fate of the cyst and not the effect of the medicine. Given the fact that pharmaceutical companies of industrial countries are not likely to invest money in discovering better drugs for Echinococcosis, a disease seen only in endemic areas of the world, one should not expect a truly effective drug for this parasitic condition becoming available soon. The problem of how and when asymptomatic liver hydatids should be treated, remains unknown. Another approach to asymptomatic liver hydatids, also originating in the West, is percutaneous needle aspiration of the cyst followed by instillation of hypertonic saline and 90% alcohol. For a number of reasons this particular form of treatment, while in line with the now fashionable mode of minimal access cannot be recommended, for two reasons: a) While univesicular liver cysts can be needle aspirated, only centrally located multivesicular hydatids are likely to rupture into major bile ducts and precipitate acute biliary obstruction. Hitting each and every small daughter cyst in these multivesiular lesions is technically impossible and Opinion