{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T15:32:56Z","timestamp":1787671976474,"version":"build-2736575974"},"reference-count":37,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:00:00Z","timestamp":1787616000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Hepatic cystic echinococcosis (HCE) is a chronic parasitic disease with a highly variable clinical course. Fistula formation represents one of its most clinically relevant complications, yet its determinants and prognostic impact remain incompletely defined.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective observational cohort study including patients with cystic echinococcosis managed at a tertiary referral centre between 1998 and 2025. Patients with hepatic involvement were classified according to the presence or absence of fistula formation. Clinical, laboratory, radiological, treatment and outcome variables were compared.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 539 patients with HCE, 87 (16.1%) developed fistula formation. Cystobiliary fistula was the predominant subtype (n=80), followed by transdiaphragmatic fistulas. Patients with fistulas were younger and more frequently symptomatic, with higher rates of complications. Fistula formation was independently associated with active cyst stages (CE1\u2013CE3), cyst diameter &amp;gt;7\u00a0cm and eosinophilia. Despite increased clinical complexity, no significant differences were observed between patients with and without fistula in recurrence, all-cause mortality, CE-related mortality or length of hospital stay.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Fistula formation in HCE identifies a subgroup of patients with larger and biologically active cysts, reflecting increased disease complexity rather than worse prognosis. When managed in specialised centres, fistulization does not appear to adversely affect long-term outcomes. Early identification of high-risk cysts may support targeted monitoring and timely intervention, particularly in endemic settings.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/trstmh\/trag098","type":"journal-article","created":{"date-parts":[[2026,8,8]],"date-time":"2026-08-08T11:51:21Z","timestamp":1786189881000},"source":"Crossref","is-referenced-by-count":0,"title":["Fistula formation in hepatic cystic echinococcosis: clinical impact, predictors, and outcomes from a 27-year cohort"],"prefix":"10.1093","author":[{"given":"Inmaculada","family":"Izquierdo\u00a0P\u00e9rez","sequence":"first","affiliation":[{"name":"Servicio de Medicina Interna, Unidad de Infecciosas, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amparo","family":"L\u00f3pez-Bernus","sequence":"additional","affiliation":[{"name":"Servicio de Medicina Interna, Unidad de Infecciosas, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Romero\u00a0Alegr\u00eda","sequence":"additional","affiliation":[{"name":"Servicio de Medicina Interna, Unidad de Infecciosas, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Montserrat","family":"Alonso-Sard\u00f3n","sequence":"additional","affiliation":[{"name":"\u00c1rea de Medicina Preventiva, Epidemiolog\u00eda y Salud P\u00fablica, Facultad de Medicina, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatriz","family":"Rodriguez\u00a0Alonso","sequence":"additional","affiliation":[{"name":"Servicio de Medicina Interna, Unidad de Infecciosas, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hugo","family":"Almeida","sequence":"additional","affiliation":[{"name":"Servicio de Medicina Interna, Unidad de Infecciosas, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josu\u00e9","family":"Pendones","sequence":"additional","affiliation":[{"name":"Servicio de Microbiolog\u00eda y Parasitolog\u00eda, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Departamento de Ciencias Biom\u00e9dicas y del Diagn\u00f3stico, Universidad de Salamanca, Centro Superior de Investigaciones Cient\u00edficas, Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javier","family":"Pardo-Lled\u00edas","sequence":"additional","affiliation":[{"name":"Servicio de Medicina Interna, Hospital Marqu\u00e9s de Valdecilla, Universidad de Cantabria, Instituto de Investigaci\u00f3n Valdecilla , Santander 39000 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2230-1256","authenticated-orcid":false,"given":"Moncef","family":"Belhassen-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Servicio de Medicina Interna, Unidad de Infecciosas, Hospital Universitario de Salamanca, Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca, e-INTRO, Centro de Investigaci\u00f3n en Enfermedades Tropicales, Universidad de Salamanca , Salamanca 37007 ,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,8,25]]},"reference":[{"issue":"1","key":"2026082511145948100_bib1","doi-asserted-by":"crossref","first-page":"e893","DOI":"10.1371\/journal.pntd.0000893","article-title":"Cystic echinococcosis in Spain: current situation and relevance for other endemic areas in Europe","volume":"5","author":"Rojo-Vazquez","year":"2011","journal-title":"PLoS Negl Trop Dis"},{"issue":"3","key":"2026082511145948100_bib2","first-page":"125","article-title":"Evoluci\u00f3n de la hidatidosis en Espa\u00f1a desde 2015 hasta 2023","volume":"32","author":"Rodr\u00edguez-Campelo","year":"2024","journal-title":"Bol Epidemiol Seman"},{"issue":"3","key":"2026082511145948100_bib3","doi-asserted-by":"crossref","first-page":"101974","DOI":"10.1016\/j.gassur.2025.101974","article-title":"Cystic echinococcosis of the liver","volume":"29","author":"Aziz","year":"2025","journal-title":"J Gastrointest Surg"},{"issue":"3","key":"2026082511145948100_bib4","doi-asserted-by":"crossref","first-page":"628","DOI":"10.4269\/ajtmh.19-0019","article-title":"Complications associated with initial clinical presentation of cystic echinococcosis: a 20-year cohort analysis","volume":"101","author":"Collado-Aliaga","year":"2019","journal-title":"Am J Trop Med Hyg"},{"issue":"5","key":"2026082511145948100_bib5","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1007\/s00383-020-04637-9","article-title":"A serious complication of liver hydatid cysts in children: cystobiliary fistulas","volume":"36","author":"Demir","year":"2020","journal-title":"Pediatr Surg Int."},{"issue":"2","key":"2026082511145948100_bib6","first-page":"214","article-title":"Pulmonary embolism as a rare complication of liver hydatid cyst: report of two cases","volume":"43","author":"Toumi","year":"2018","journal-title":"Iran J Med Sci"},{"issue":"1","key":"2026082511145948100_bib7","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1111\/j.1478-3231.2009.02116.x","article-title":"Surgical management of liver hydatidosis: a multicentre series of 1412 patients","volume":"30","author":"Secchi","year":"2010","journal-title":"Liver Int"},{"issue":"11","key":"2026082511145948100_bib8","doi-asserted-by":"crossref","first-page":"1249","DOI":"10.1001\/archsurg.136.11.1249","article-title":"Intrabiliary rupture of a hepatic hydatid cyst: associated clinical factors and proper management","volume":"136","author":"Atli","year":"2001","journal-title":"Arch Surg"},{"key":"2026082511145948100_bib9","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1007\/s005950200107","article-title":"Surgical management of spontaneous intrabiliary rupture of hydatid liver cysts","volume":"32","author":"Bedirli","year":"2002","journal-title":"Surg Today"},{"issue":"1","key":"2026082511145948100_bib10","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1159\/000018582","article-title":"Rupture of the hydatid disease of the liver into the biliary tracts","volume":"15","author":"Paksoy","year":"1998","journal-title":"Dig Surg"},{"issue":"4","key":"2026082511145948100_bib11","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1016\/j.ijsu.2009.06.012","article-title":"Asymptomatic occult cysto-biliary communication without bile into cavity of the liver hydatid cyst: a pitfall in conservative surgery","volume":"7","author":"Unalp","year":"2009","journal-title":"Int J Surg"},{"issue":"6","key":"2026082511145948100_bib12","doi-asserted-by":"crossref","first-page":"1408","DOI":"10.1016\/S0168-8278(97)80479-5","article-title":"Resolution of hydatid liver cyst by spontaneous rupture into the biliary tract","volume":"26","author":"Becker","year":"1997","journal-title":"J Hepatol"},{"issue":"2","key":"2026082511145948100_bib13","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/S0002-9610(02)01202-3","article-title":"Distribution of hydatid cysts into the liver with reference to cystobiliary communications and cavity-related complications","volume":"185","author":"Kayaalp","year":"2003","journal-title":"Am J Surg"},{"key":"2026082511145948100_bib14","doi-asserted-by":"crossref","first-page":"881","DOI":"10.1007\/s00423-012-0926-8","article-title":"Cysto-biliary communication in liver hydatidosis","volume":"397","author":"Ramia","year":"2012","journal-title":"Langenbecks Arch Surg"},{"issue":"1","key":"2026082511145948100_bib15","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1007\/s00383-025-06041-7","article-title":"A study of hepatic hydatid cysts, focusing on cystobiliary fistula formation in children","volume":"41","author":"Tutu\u015f","year":"2025","journal-title":"Pediatr Surg Int"},{"issue":"3","key":"2026082511145948100_bib16","first-page":"257","article-title":"Pulmonary cystic echinococcosis","volume":"16","author":"Santivanez","year":"2010","journal-title":"Curr Opin Pulm Med"},{"issue":"2","key":"2026082511145948100_bib17","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1055\/s-0030-1270702","article-title":"Abdominothoracic fistulas due to complicated echinococcosis","volume":"60","author":"Karamustafaoglu","year":"2012","journal-title":"Thorac Cardiovasc Surg"},{"issue":"3","key":"2026082511145948100_bib18","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1067\/msy.2002.118713","article-title":"Spontaneous rupture of primary musculoskeletal hydatid cyst","volume":"132","author":"Natarajan","year":"2002","journal-title":"Surgery"},{"issue":"6","key":"2026082511145948100_bib19","doi-asserted-by":"crossref","first-page":"710","DOI":"10.4067\/S0716-10182018000600710","article-title":"Equinococosis qust\u00edca m\u00fasculo-esquel\u00e9tica primaria de evoluci\u00f3n cr\u00f3nica","volume":"35","author":"Botello","year":"2018","journal-title":"Rev Chil Infect"},{"issue":"1","key":"2026082511145948100_bib20","doi-asserted-by":"crossref","first-page":"2458420","DOI":"10.1080\/20565623.2025.2458420","article-title":"Preoperative predictive factors of cystobiliary fistulas in liver hydatid cysts: results of a monocentric study","volume":"11","author":"Jarrar","year":"2025","journal-title":"Future Sci OA"},{"key":"2026082511145948100_bib21","doi-asserted-by":"crossref","first-page":"995","DOI":"10.2147\/TCRM.S104400","article-title":"Value of cyst localization to predict cystobiliary communication in patients undergoing conservative surgery with hydatid cyst","volume":"12","author":"Bircan\u00a0Alan","year":"2016","journal-title":"Ther Clin Risk Manage"},{"issue":"7","key":"2026082511145948100_bib22","doi-asserted-by":"crossref","first-page":"670","DOI":"10.1177\/0218492316658374","article-title":"Pulmonary hydatid cysts: the naturally occurring models for rupture","volume":"24","author":"Ashour","year":"2016","journal-title":"Asian Cardiovasc Thorac Ann"},{"key":"2026082511145948100_bib23","doi-asserted-by":"crossref","first-page":"1539","DOI":"10.1007\/s11748-021-01670-w","article-title":"Clinical features and treatment of bronchial rupture of pulmonary hydatid cyst in children: a retrospective study of 36 patients","volume":"69","author":"Kabiri","year":"2021","journal-title":"Gen Thorac Cardiovasc Surg"},{"issue":"1","key":"2026082511145948100_bib24","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.actatropica.2009.11.001","article-title":"Expert consensus for the diagnosis and treatment of cystic and alveolar echinococcosis in humans","volume":"114","author":"Brunetti","year":"2010","journal-title":"Acta Trop"},{"issue":"1","key":"2026082511145948100_bib25","first-page":"62","article-title":"Diagnosis and treatment of imported eosinophilia in travellers and immigrants: recommendations of the Spanish Society of Tropical Medicine and International Health (SEMTSI)","volume":"30","author":"Salas-Coronas","year":"2016","journal-title":"Rev Espan Quimioter"},{"issue":"2","key":"2026082511145948100_bib26","doi-asserted-by":"crossref","first-page":"125","DOI":"10.5152\/tjg.2017.17553","article-title":"Cystobiliary communication in hepatic hydatid cyst: predictors and outcome","volume":"28","author":"Nakeeb","year":"2017","journal-title":"Turk J Gastroenterol"},{"key":"2026082511145948100_bib27","doi-asserted-by":"crossref","first-page":"3884","DOI":"10.1007\/s00268-020-05661-5","article-title":"Nomogram analysis and internal validation to predict the risk of cystobiliary communication in patients undergoing hydatid liver cyst surgery","volume":"44","author":"Wang","year":"2020","journal-title":"World J Surg"},{"issue":"6","key":"2026082511145948100_bib28","doi-asserted-by":"crossref","first-page":"385","DOI":"10.1016\/S1473-3099(07)70134-2","article-title":"Prevention and control of cystic echinococcosis","volume":"7","author":"Craig","year":"2007","journal-title":"Lancet Infect Dis"},{"issue":"3","key":"2026082511145948100_bib29","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1128\/JCM.02420-15","article-title":"Cystic echinococcosis","volume":"54","author":"Agudelo\u00a0Higuita","year":"2016","journal-title":"J Clin Microbiol"},{"issue":"1","key":"2026082511145948100_bib30","first-page":"16","article-title":"Eosinophilia and cystic echinococcosis: what is the relationship?","volume":"114","author":"Collado-Aliaga","year":"2020","journal-title":"Trans R Soc Trop Med Hyg"},{"issue":"6","key":"2026082511145948100_bib31","doi-asserted-by":"crossref","first-page":"e1154","DOI":"10.1371\/journal.pntd.0001154","article-title":"Justified concern or exaggerated fear: the risk of anaphylaxis in percutaneous treatment of cystic echinococcosis-a systematic literature review","volume":"5","author":"Neumayr","year":"2011","journal-title":"PLoS Negl Trop Dis"},{"issue":"5","key":"2026082511145948100_bib32","doi-asserted-by":"crossref","first-page":"568","DOI":"10.1111\/j.1398-9995.1992.tb00683.x","article-title":"Anaphylactic shock by rupture of hydatid hepatic cyst","volume":"47","author":"de\u00a0San\u00a0Pedro","year":"1992","journal-title":"Allergy"},{"key":"2026082511145948100_bib33","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1186\/1471-2482-10-16","article-title":"Predictive model of biliocystic communication in liver hydatid cysts using classification and regression tree analysis","volume":"10","author":"El\u00a0Malki","year":"2010","journal-title":"BMC Surg"},{"issue":"11","key":"2026082511145948100_bib34","doi-asserted-by":"crossref","first-page":"1182","DOI":"10.1002\/bjs.1800791127","article-title":"Significance of intracystic pressure in abdominal hydatid disease","volume":"79","author":"Yalin","year":"1992","journal-title":"Br J Surg"},{"issue":"10","key":"2026082511145948100_bib35","doi-asserted-by":"crossref","first-page":"e0011724","DOI":"10.1371\/journal.pntd.0011724","article-title":"Risk factors and management of biliary leakage after endocystectomy for hepatic cystic echinococcosis","volume":"17","author":"Abbasi\u00a0Dezfouli","year":"2023","journal-title":"PLoS Negl Trop Dis"},{"issue":"1","key":"2026082511145948100_bib36","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1007\/s002680020005","article-title":"Management of liver hydatid cysts with a large biliocystic fistula: multicenter retrospective study","volume":"25","author":"Zaouche","year":"2001","journal-title":"World J Surg"},{"issue":"3","key":"2026082511145948100_bib37","doi-asserted-by":"crossref","first-page":"e91342","DOI":"10.1371\/journal.pone.0091342","article-title":"Study of hydatidosis-attributed mortality in endemic area","volume":"9","author":"Belhassen-Garc\u00eda","year":"2014","journal-title":"PLoS One"}],"container-title":["Transactions of The Royal Society of Tropical Medicine and Hygiene"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/trstmh\/advance-article-pdf\/doi\/10.1093\/trstmh\/trag098\/70784508\/trag098.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/trstmh\/advance-article-pdf\/doi\/10.1093\/trstmh\/trag098\/70784508\/trag098.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T15:15:10Z","timestamp":1787670910000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/trstmh\/advance-article\/doi\/10.1093\/trstmh\/trag098\/8770389"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,25]]},"references-count":37,"URL":"https:\/\/doi.org\/10.1093\/trstmh\/trag098","relation":{},"ISSN":["0035-9203","1878-3503"],"issn-type":[{"value":"0035-9203","type":"print"},{"value":"1878-3503","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,25]]},"article-number":"trag098"}}