Correspondence

Safety of percutaneous drainage for liver hydatid cysts

Losanoff and associates1 expressed their concern that the safety and effectiveness of percutaneous therapy (e.g., the PAIR [puncture, aspiration, injection, reaspiration] technique) for cystic echinococcosis has not been fully established. We believe that extensive experience in many countries has found that when physicians use a protocol that addresses the major safety issues, such as anaphylactic shock, sclerosing cholangitis and peritoneal dissemination, the safety and efficacy of this approach to treatment is comparable or superior to conventional surgical techniques.

Sclerosing cholangitis has been described in the literature as a consequence of surgery2 but rarely, if ever, after PAIR. In our protocol,3 we inject hypertonic contrast agent into the cyst cavity after aspiration of the fluid. This allows the detection of communications with the biliary tree that might have gone unnoticed at the time of imaging because of intra-cystic pressure. If communication is detected, we do not inject alcohol, but simply leave the contrast agent inside. Being hypertonic, the agent is scolicidal but produces no damage to the biliary epithelium. Peritoneal dissemination of inadvertently released protoscolices is prevented by prophylactic administration of albendazole (as is routine postoperatively).

Although long-term (5–10 yr) follow-up is needed to assess the rate of postoperative recurrence or dissemination, some reports have addressed this aspect.4 Our findings from patients followed up for more than 10 years (unpublished data), based on whole body CT scanning performed on 5 patients show no signs of dissemination or recurrence in the peritoneum or at any other site. As for serologic surveillance, we do not believe that at the present stage of development available tests can be relied upon for follow-up. Current research performed at our centre is designed to evaluate whether immunoglobulin E antibodies or total and specific immunoglobulin G subclasses can be used to determine the outcome of treatment.