veterinaryВетеринария сегодняVeterinary Science Today2304-196X2658-6959"Veinard"10.29326/2304-196X-2026-15-3-236-240veterinary-1036Research ArticleОБЗОРЫ | БОЛЕЗНИ ЛОШАДЕЙREVIEWS | EQUINE DISEASESОбзор клинических проявлений питиоза лошадей (Pythium insidiosum)An overview of clinical features of equine pythiosis (Pythium insidiosum)https://orcid.org/0009-0003-4707-9000PinheiroJúlia A. SilvaPinheiroJúlia A. Silva

Júlia A. Silva Pinheiro, студент бакалавриата, Университетский центр UNA, кампус «Зеленая линия», факультет ветеринарной медицины

Minas Gerais

Júlia A. Silva Pinheiro, Undergraduate Student, Centro  Universitário UNA, Campus Linha Verde, Faculdade de Medicina  Veterinária

Campus Linha Verde, Belo Horizonte, Minas Gerais

juliapinheiro1306@gmail.comCentro Universitário UNAБразилияCentro Universitário UNABrazil202623092026153236240Copyright © Pinheiro J., 20262026Pinheiro J.Pinheiro J.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://veterinary.arriah.ru/jour/article/view/1036

Питиоз – это хроническое гранулематозное заболевание, поражающее различные виды животных, чаще всего лошадей. Распространено в тропическом, субтропическом и умеренном климате, тесно связано с влажной почвой и со стоячей водой – болотами и прудами. Возбудитель обитает на водных растениях, образуя подвижные зооспоры, которые проникают в организм хозяина через поврежденную кожу. В основе патогенеза лежит преимущественно Th2-тип иммунного ответа, для которого характерны продукция интерлейкинов IL-4, IL-5 и IL-13, а также выраженная эозинофилия и гранулематозное воспаление, способствующее длительной персистенции возбудителя в тканях хозяина. Клинически болезнь проявляется формированием эозинофильных гранулем, содержащих некротические массы, состоящие из гиф, коллагена и воспалительных клеток. Для терапии применяются различные подходы, включающие использование противогрибковых препаратов, хирургическое вмешательство и иммунотерапию. Хирургическое иссечение в сочетании с иммунотерапией считается наиболее эффективной стратегией, однако лечение сопряжено с трудностями из-за уникальных характеристик возбудителя: в отличие от истинных грибов, его клеточная стенка содержит целлюлозу и β-глюканы. Целью данного исследования является анализ биологических и инфекционных аспектов Pythium insidiosum, а также характеристика иммунопатогенеза питиоза у лошадей с акцентом на взаимодействие между этиологическим агентом и иммунным ответом хозяина.

Pythiosis is a chronic granulomatous disease affecting various animal species, most commonly equines. It occurs in tropical, subtropical, or temperate climates and is associated with waterlogged areas, such as swamps and ponds. The causative microorganism parasitizes aquatic plants and produces motile zoospores capable of infecting hosts through cutaneous lesions. Pathogenesis is associated with a predominant Th2-type immune response, characterized by the production of interleukins such as IL-4, IL-5, and IL-13, as well as intense eosinophilia and granulomatous inflammation, which contributes to the agent’s persistence in tissues. Clinically, the disease is characterized by the formation of eosinophilic granulomas containing “kunkers”, necrotic masses composed of hyphae, collagen, and inflammatory cells. Various therapeutic approaches have been employed, including the use of antifungals, surgery, and immunotherapy. Surgical removal combined with immunotherapy is considered the most effective strategy, although treatment poses challenges due to the agent’s unique characteristics; unlike true fungi, its cell wall contains cellulose and β-glucans. This study aims to analyze the biological and infectious aspects of Pythium insidiosum and to characterize the immunopathogenesis of equine pythiosis, focusing on the interaction between the etiological agent and the host immune response.

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The authors declare that there are no conflicts of interest present.