Relation between serology and grow-up time in atypically localized hydatic cysts.

OBJECTIVE Hydatic cyst is a parasitic disease caused by the larvae of Echinococcus granulosus. In the study, the aim is to evaluate the relation between serology and grow-up time in atypically localized cysts. METHODS Retrospectively, all the patients with hydatic disease between December 2004 and May 2012 were screened from the hospital database. Hydatic cyst localization other than the liver and lungs were accepted as atypical localization. RESULTS There were 325 patients with a diagnosis of hydatic disease. Most common localizations of the cysts were the liver (72.8%) and lungs (21%). Atypically localized cyst rate was 6.4% (n: 21). The most common atypical localization was the spleen (2.4%). 80.9% of atypically localized cysts were primary cases. In 3 cases with primary intramuscular hydatic cyst and 2 cases with primary subcutaneous hydatic cysts, serology was negative. CONCLUSION The relation between the hydatid cyst and the host is the main factor in serological tests and grow-up time. In tissues with a weaker cellular immunity like muscle and subcutaneous tissue, serology tends to be negative and grow-up time to be faster. In atypically localized cysts,hematogenous dissemination cannot explain the pathogenesis fully. Therefore, lymphatic dissemination should be kept in mind.