BackgroundCystic echinococcosis (CE) is a neglected tropical disease which affects more than 1 million people globally, causing a loss of 1-3 million disability-adjusted life years (DALYs) and a financial burden of US$ 3 billion annually.The two most commonly involved organs are the liver and the lungs with involvement in 75% and 5 -15% of cases respectively. The rest of the body can be involved in up to 10% of cases. In this study, we aim to explore the presentation, treatment and outcomes of CE in unusual locations.MethodsRetrospective review of charts of 225 patients of CE admitted at Aga Khan Hospital, Karachi from 2007-2017 was done. Demographic information, date of admission, clinical presentation, laboratory and radiological findings, histopathology reports (where applicable), treatment course and outcomes were noted.ResultsCE occurred in the liver in 146 (64.9%) patients, in the lungs in 55 (24.4%) patients and in unusual locations in 24 (10.7%) patients. Primary involvement of unusual locations was seen in 22 (91.7%) cases. Amongst the 24 patients with disease in unusual locations, 13 (54.2%) were males and 11 (45.8%) were females and the median age of these patients was 43 years. Fever and dyspnea were the most common presenting complains, occurring in 5 (20.8%) patients each followed by epigastric abdominal pain and weight loss occurring in 3(12.5%) patients each. Spleen was the most common unusual location for CE with four cases (16.7%) of splenic involvement occurring, followed by cardiac, spinal and mediastinal involvement occurring in three (12.5%) patients each. Other unusual locations included the abdominal cavity, bones, breast, kidney, seminal vesicle, brain, adrenal glands and the inguinal region. The treatment courses employed were a) medical, consisting of oral albendazole use(400 mg twice daily), b) surgical c) combined (medical plus surgical) therapy. Combined surgical and medical therapy, was the most common modality employed, with it being given to 14 (58.3%) patients. Surgery only was performed in 5 (20.8%) patients while medical therapy only to 3 (12.5%) patients. Resolution of the disease was seen in 19 (79.2%) patients on follow up imaging. Recurrence occurred in 4 (16.7%) and mortality in 1 patient. Two patients (8.3%) were lost to follow up.ConclusionsCE can be challenging to diagnose especially when it occurs in unusual locations. CE must be included in the differential diagnosis of a cystic lesion in any organ of the body, especially in endemic areas, to ensure timely diagnosis and treatment, to prevent morbidity and mortality associated with chronicity of the disease.