{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T00:18:52Z","timestamp":1792801132082,"version":"4.5.0"},"reference-count":38,"publisher":"SAGE Publications","issue":"1","license":[{"start":{"date-parts":[[2018,9,20]],"date-time":"2018-09-20T00:00:00Z","timestamp":1537401600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Vet Pathol"],"published-print":{"date-parts":[[2019,1]]},"abstract":"<jats:p>Severe Perkinsea infection (SPI) is an emerging disease of frogs responsible for mass mortalities of tadpoles across the United States. It is caused by protozoa belonging to the phylum Perkinsozoa that form a distinct group referred to as the Pathogenic Perkinsea Clade of frogs. In this work, we provide detailed description of gross and histologic lesions from 178 naturally infected tadpoles, including 10 species from 22 mortality events and 6 amphibian health monitoring studies from diverse geographic areas. On external examination, we observed abdominal distension (10, 5.6%), cutaneous erythema and petechia (3, 1.7%), subcutaneous edema (3, 1.7%), and areas of white skin discoloration (3, 1.7%). On macroscopic examination of internal organs, we found hepatomegaly (68, 38.2%), splenomegaly (51, 28.7%), nephromegaly (47, 26.4%), ascites (15, 8.4%), segmental irregular thickening and white discoloration of the intestine (8, 4.5%), pancreatomegaly (4, 2.2%), and pancreatic petechia (1, 0.6%). Histologically, over 60% of the liver (148\/165, 89.7%), kidney (113\/147, 76.9%), spleen (96\/97, 99%), and pancreas (46\/68, 67.6%) were invaded by myriad intracellular and extracellular Perkinsea hypnospore-like and trophozoite-like organisms. Numerous other tissues were affected to a lesser extent. Mild histiocytic inflammation with fewer lymphocytes or eosinophils was commonly observed in areas of infection that were not obscured by lympho-granulocytic hematopoietic tissue. In light of these observations, we suggest a logical pathogenesis sequence. Finally, we propose a \u201ccase definition\u201d for SPI to promote standardized communication of results and prevent misdiagnosis with epidemiological and pathologically overlapping diseases such as ranavirosis.<\/jats:p>","DOI":"10.1177\/0300985818798132","type":"journal-article","created":{"date-parts":[[2018,9,21]],"date-time":"2018-09-21T02:21:40Z","timestamp":1537496500000},"page":"133-142","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":14,"title":["Pathology and Case Definition of Severe Perkinsea Infection of Frogs"],"prefix":"10.1177","volume":"56","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9380-7254","authenticated-orcid":false,"given":"Marcos","family":"Isidoro-Ayza","sequence":"first","affiliation":[{"name":"Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA"},{"name":"National Wildlife Health Center\u2013US Geological Survey, Madison, WI, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel A.","family":"Grear","sequence":"additional","affiliation":[{"name":"National Wildlife Health Center\u2013US Geological Survey, Madison, WI, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aur\u00e9lie","family":"Chambouvet","sequence":"additional","affiliation":[{"name":"Laboratoire des Sciences de l\u2019Environnement Marin (LEMAR), UMR6539 UBO\/CNRS\/IRD\/IFREMER, Institut Universitaire Europ\u00e9en de la Mer (IUEM), Technopole Brest Iroise, Plouzan\u00e9, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2018,9,20]]},"reference":[{"key":"bibr1-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1508681112"},{"key":"bibr2-0300985818798132","first-page":"469","volume":"14","author":"Auzoux-Bordenave S.","year":"1995","journal-title":"J Shellfish Res"},{"key":"bibr3-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1016\/j.jip.2015.07.006"},{"key":"bibr4-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1007\/s10393-016-1120-1"},{"key":"bibr5-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejop.2012.07.004"},{"key":"bibr6-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1500163112"},{"key":"bibr7-0300985818798132","first-page":"258","volume-title":"Pathology of Domestic Animals","volume":"2","author":"Cullen JM","year":"2016"},{"key":"bibr8-0300985818798132","doi-asserted-by":"publisher","DOI":"10.3201\/eid0506.990601"},{"key":"bibr9-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1007\/s10393-007-0115-3"},{"key":"bibr10-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1007\/s10393-009-0271-8"},{"key":"bibr11-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.micro.091208.073435"},{"key":"bibr12-0300985818798132","first-page":"45","volume":"15","author":"Ford SE","year":"1996","journal-title":"J Shellfish Res"},{"key":"bibr13-0300985818798132","first-page":"59","volume":"160","author":"Frank G.","year":"1988","journal-title":"J Anat"},{"key":"bibr14-0300985818798132","first-page":"183","volume":"16","author":"Gosner KL","year":"1960","journal-title":"Herpetologica"},{"key":"bibr15-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-319-13755-1_8"},{"key":"bibr16-0300985818798132","doi-asserted-by":"publisher","DOI":"10.3354\/dao02138"},{"key":"bibr17-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1111\/j.1749-6632.2002.tb04400.x"},{"key":"bibr18-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1016\/S1521-6918(03)00016-7"},{"key":"bibr19-0300985818798132","author":"Isidoro-Ayza M","journal-title":"Accept Publ J Wildl Dis"},{"key":"bibr20-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-017-10456-1"},{"key":"bibr21-0300985818798132","doi-asserted-by":"publisher","DOI":"10.3354\/dao02539"},{"key":"bibr22-0300985818798132","doi-asserted-by":"publisher","DOI":"10.3354\/dao02625"},{"key":"bibr23-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1006\/viro.1996.0080"},{"key":"bibr24-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-319-13755-1_7"},{"key":"bibr25-0300985818798132","doi-asserted-by":"publisher","DOI":"10.3390\/v3112351"},{"key":"bibr26-0300985818798132","volume-title":"Infection with Ranavirus","author":"OIE","year":"2007"},{"key":"bibr27-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1016\/j.jip.2010.07.006"},{"key":"bibr28-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1177\/0300985817699861"},{"key":"bibr29-0300985818798132","volume-title":"Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America","author":"Powell R","year":"2016"},{"key":"bibr30-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1002\/dvdy.21891"},{"key":"bibr31-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1111\/j.1523-1739.1988.tb00334.x"},{"key":"bibr32-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1016\/j.jip.2013.06.001"},{"key":"bibr33-0300985818798132","volume-title":"A Field Guide to Western Reptiles and Amphibians","author":"Stebbins RC","year":"2003"},{"key":"bibr34-0300985818798132","unstructured":"IUCN 2018. The IUCN Red List of Threatened Species. Version 2018-1. Available at: http:\/\/www.iucnredlist.org. Accessed July 25 2018."},{"key":"bibr35-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-1795.2010.00373.x"},{"key":"bibr36-0300985818798132","doi-asserted-by":"publisher","DOI":"10.1186\/s13567-015-0266-0"},{"key":"bibr37-0300985818798132","first-page":"16","volume":"50","author":"Waki T","year":"2015","journal-title":"\u9b5a\u75c5\u7814\u7a76"},{"key":"bibr38-0300985818798132","first-page":"207","volume":"47","author":"White C","year":"2016","journal-title":"Herpetol Rev"}],"container-title":["Veterinary Pathology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/0300985818798132","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/0300985818798132","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/0300985818798132","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T18:59:09Z","timestamp":1777661949000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/0300985818798132"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,9,20]]},"references-count":38,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2019,1]]}},"alternative-id":["10.1177\/0300985818798132"],"URL":"https:\/\/doi.org\/10.1177\/0300985818798132","relation":{},"ISSN":["0300-9858","1544-2217"],"issn-type":[{"value":"0300-9858","type":"print"},{"value":"1544-2217","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,9,20]]}}}