{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T06:05:28Z","timestamp":1771308328719,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T00:00:00Z","timestamp":1771027200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Instituto Oswaldo Cruz","doi-asserted-by":"publisher","award":["309493\/2025-0"],"award-info":[{"award-number":["309493\/2025-0"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Instituto Oswaldo Cruz","doi-asserted-by":"publisher","award":["317510-2021-5"],"award-info":[{"award-number":["317510-2021-5"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Instituto Oswaldo Cruz","doi-asserted-by":"publisher","award":["307933\/2025-3"],"award-info":[{"award-number":["307933\/2025-3"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Faperj: Proc.","award":["200.528\/2023"],"award-info":[{"award-number":["200.528\/2023"]}]},{"DOI":"10.13039\/501100003593","name":"CNPq","doi-asserted-by":"crossref","award":["465489\/2014-1"],"award-info":[{"award-number":["465489\/2014-1"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Canine visceral leishmaniasis (CVL), caused by Leishmania infantum, is a multisystemic disease in which ocular involvement is frequent but often underestimated. This study aimed to comprehensively evaluate the clinical, ophthalmological, parasitological, hematological, biochemical, and histopathological alterations in dogs naturally infected with L. infantum from an endemic area of northeastern Brazil, with special emphasis on the relationship between ocular manifestations and systemic disease. Twenty-five symptomatic dogs were evaluated through clinical and ophthalmological examinations, parasitological culture, PCR, laboratory analyses, and histopathology of ocular and periocular tissues. Ocular alterations were observed in 80% of the animals, predominantly bilateral and frequently associated with multiple concurrent lesions, including ocular discharge, conjunctivitis, blepharitis, uveitis, and corneal opacity. Functional ophthalmological tests revealed keratoconjunctivitis sicca and corneal ulcers in a substantial proportion of dogs. Hematological abnormalities were highly prevalent, particularly anemia and thrombocytopenia. Comparative analysis demonstrated that dogs with ocular involvement exhibited significantly higher leukocyte counts and segmented neutrophils, as well as increased AST levels, indicating an enhanced systemic inflammatory response. Histopathological examination revealed intense plasmacytic inflammatory infiltrates and the presence of amastigote forms in ocular and periocular tissues, indicating that both immune-mediated and parasite-driven mechanisms could be involved in disease pathogenesis. Collectively, these findings underscore ocular involvement as a clinically relevant manifestation of CVL and reinforce the importance of routine ophthalmological evaluation in clinical management.<\/jats:p>","DOI":"10.3390\/pathogens15020217","type":"journal-article","created":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T11:11:28Z","timestamp":1771240288000},"page":"217","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ocular Involvement as a Key Marker of Systemic Disease in Dogs Naturally Infected with Leishmania infantum: Clinical, Laboratory, and Histopathological Insights"],"prefix":"10.3390","volume":"15","author":[{"given":"Caroline","family":"Magalh\u00e3es-Cunha","sequence":"first","affiliation":[{"name":"Laborat\u00f3rio de Protozoologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"},{"name":"Programa de P\u00f3s-gradua\u00e7\u00e3o em Medicina Tropical, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2167-3725","authenticated-orcid":false,"given":"Ana L\u00facia","family":"Abreu-Silva","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Patologia Veterin\u00e1ria, Departamento de Patologia, Universidade Estadual do Maranh\u00e3o, Av. Louren\u00e7o Vieira da Silva, 1000, Jardim S\u00e3o Crist\u00f3v\u00e3o, S\u00e3o Lu\u00eds 65055-310, MA, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcelo","family":"Pelajo-Machado","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Medicina Experimental e Sa\u00fade, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Celeste da Silva Freitas de","family":"Souza","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Protozoologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karen Lebreiro dos","family":"Santos","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Protozoologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6613-930X","authenticated-orcid":false,"given":"Lucas Almeida","family":"Zangirolami","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Protozoologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"},{"name":"Programa de P\u00f3s-gradua\u00e7\u00e3o em Biologia Parasit\u00e1ria, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2026-1836","authenticated-orcid":false,"given":"Fl\u00e1via de Oliveira","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Protozoologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro 21040-360, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"K\u00e1tia da Silva","family":"Calabrese","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Protozoologia, Instituto Oswaldo Cruz, Fiocruz, Av. 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