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Abstract
The vitreous humor is a biological matrix that has been poorly explored in Canine Visceral Leishmaniasis (CVL). Its study represent an alternative approach for investigating Leishmania infantum. This report describes the molecular detection and isolation of L. infantum in the vitreous humor of a dog from an endemic area in northwestern São Paulo State, Brazil. An adult male dog presented with progressive weight loss, lymphadenomegaly, and signs of bilateral chronic uveitis associated with vision loss. Infection was confirmed by Dual Path Platform (DPP®) and ELISA serological tests. Lymph node and bone marrow samples were collected before euthanasia; spleen, liver, cornea, lens, and vitreous humor samples were collected afterwards. Samples of spleen, liver, lymph node, and ocular tissues were analyzed in parasitological culture. Additionally, real-time PCR (qPCR) was performed on bone marrow and ocular samples, using the canine GAPDH gene as an endogenous quality control. The cornea and lens yielded negative results in both methodologies. qPCR confirmed the presence of L. infantum DNA in the bone marrow and vitreous humor. The isolation and molecular detection of L. infantum in the vitreous humor demonstrate intraocular involvement in CVL and reinforce the parasite’s presence in different tissue compartments. These findings broaden our understanding of the tissue tropism of L. infantum and contribute to knowledge about the parasite’s dissemination in the ocular tissues of naturally infected dogs.
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Copyright (c) 2026 Denise Maria Bussoni Bertollo, Graziela Matiel Doimo Bailon, Fernanda Modesto Tolentino Binhardi, Ana Beatriz Pinheiro da Silva, Isabel Cristina Brasil Boska, Ricardo Gava, Vera Lucia Pereira-Chioccola, Jose Eduardo Tolezano