epidemiological, clinical and paraclinical study of hydatid cysts in three educational medical centers in 10 years

background: echinococcosis or hydatidosis, caused by the larval stage of echinococcus granulosus (e. granulosus), is an important public health problem in many areas of the world  and  iran is a country of endemic situation for hydatidosis in the present study, we evaluated epidemiological, complications and clinical characteristics of hydatidosis at three university medical centers in tehran over a 10-year period. m aterials and methods: this is a descriptive cross-sectional study performed in patients with hydatid cysts. information about age, gender, number of cysts, organ involvement, morbidity and mortality and relapse were collected from medical records of hydatid patients. paraclinic information such as ct scan, mri, ultrasound, complete blood count, pathological diagnosis and complication of disease were collected. r es ults: overall, 81 patients, 35 (43.2%) male and 46 (56.8%) female, who were diagnosed as having hydatid cyst by clinical and radiological findings, with pathologic documentation were studied in three university medical center registries over a 10-year period (2003- 2012) in tehran. fourteen patients (17% of cases) had complications resulting from this disease. patients' age ranged from 5 to 86 years, and the peak prevalence of the disease was between 20 and 40 (34% of cases). c onclusion: iran  is a country of endemic situation for hydatidosis. prevalence rate of hydatidosis in iran was reported to be 0.61-2 in 100000 populations . the highest  rate of infection and complications were in patients of 20-40 years age. clinical examination revealed that abdominal pain was the most common complaint and was present in 51.7% of the cases. other most common complain were cough, abdominal mass, dyspnea, icterus, chest pain, dyspepsia, back pain and seizure; and it was result of occupying effect of cysts in organs. this is similar with previous studies in iran