Journals / İzmir Tıp Fakültesi Dergisi / 2026 / Cilt: 5 Sayı: 3

SILENT INVADERS OF THE BRAIN: NEUROIMMUNOLOGICAL MECHANISMS, NEUROLOGICAL AND PSYCHIATRIC EFFECTS OF PARASITIC INFECTIONS

BEYNİ ETKİLEYEN SESSIZ İSTİLACILAR: PARAZİTER ENFEKSİYONLARIN NÖROİMMÜNOLOJİK MEKANİZMALARI, NÖROLOJİK VE PSİKİYATRİK ETKİLERİ

Pınar Şimşek(İZMİR DEMOKRASİ ÜNİVERSİTESİ, SAĞLIK BİLİMLERİ ENSTİTÜSÜ)0009-0009-5762-2488
Hatice Kübra Beytekin(İZMİR DEMOKRASİ ÜNİVERSİTESİ, SAĞLIK BİLİMLERİ ENSTİTÜSÜ)0009-0005-3336-7786
Orhan Doğan(İZMİR DEMOKRASİ ÜNİVERSİTESİ, SAĞLIK BİLİMLERİ ENSTİTÜSÜ)0009-0008-8501-1564
Nurbanu Sezak(İZMİR DEMOKRASİ ÜNİVERSİTESİ, TIP FAKÜLTESİ)0000-0001-9472-1340
Gulden Diniz(İZMİR DEMOKRASİ ÜNİVERSİTESİ, TIP FAKÜLTESİ)0000-0003-1512-7584
Pages
227–237
Publication Date
2026-09-30
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Further well-designed prospective and multidisciplinary studies are required to clarify the underlying mechanisms and their clinical significance.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Parasitic infections remain a major global public health concern and may affect not only the gastrointestinal tract and other organs but also the central nervous system.
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Key Findings & Data:Growing evidence from the field of neuroparasitology indicates that several parasites contribute to neurological and psychiatric manifestations through direct tissue invasion as well as neuroinflammation, glial cell activation, blood-brain barrier disruption, and alterations in neurotransmitter metabolism.
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Conclusion & Impact:Further well-designed prospective and multidisciplinary studies are required to clarify the underlying mechanisms and their clinical significance.
🔬Design:Review & Systematic Survey
📍Scope:Comprehensive Sample
⚙️Variables:Paraziter enfeksiyonlar · nöroparazitolojş · nöroinflamasyon

Abstract

Parasitic infections remain a major global public health concern and may affect not only the gastrointestinal tract and other organs but also the central nervous system. Growing evidence from the field of neuroparasitology indicates that several parasites contribute to neurological and psychiatric manifestations through direct tissue invasion as well as neuroinflammation, glial cell activation, blood-brain barrier disruption, and alterations in neurotransmitter metabolism. This review summarizes the neuroimmunological mechanisms and neuropsychiatric consequences of the major parasitic infections involving the central nervous system. Particular emphasis is placed on infections caused by Toxoplasma gondii, Taenia solium, Plasmodium falciparum, Trypanosoma brucei, Toxocara spp., and free-living amoebae, highlighting their associations with epilepsy, encephalitis, cognitive impairment, behavioral changes, and selected psychiatric disorders. Current evidence regarding the roles of blood-brain barrier dysfunction, microglial and astrocytic activation, cytokine-mediated chronic neuroinflammation, the gut-brain axis, and neurotransmitter dysregulation is also reviewed. Although accumulating evidence suggests an association between several parasitic infections and neuropsychiatric disorders, causality has not yet been conclusively established for most conditions. Further well-designed prospective and multidisciplinary studies are required to clarify the underlying mechanisms and their clinical significance.

Özet

Paraziter enfeksiyonlar, dünya genelinde önemli bir halk sağlığı sorunu olmaya devam etmekte olup, yalnızca gastrointestinal sistem veya diğer organları değil, santral sinir sistemini de etkileyebilmektedir. Son yıllarda nöroparazitoloji alanında elde edilen bulgular, birçok parazitin doğrudan doku invazyonunun yanı sıra nöroinflamasyon, glial hücre aktivasyonu, kan-beyin bariyerinde bozulma ve nörotransmitter metabolizmasındaki değişiklikler aracılığıyla nörolojik ve psikiyatrik bozuklukların gelişimine katkıda bulunabileceğini göstermektedir. Bu derlemede, santral sinir sistemini etkileyen başlıca paraziter enfeksiyonlar ile bunların nöroimmünolojik mekanizmaları ve nöropsikiyatrik sonuçları güncel literatür ışığında değerlendirilmiştir. Özellikle Toxoplasma gondii, Taenia solium, Plasmodium falciparum, Trypanosoma brucei, Toxocara spp. ve serbest yaşayan amiplerin neden olduğu enfeksiyonlar ele alınmış; bu enfeksiyonların epilepsi, ensefalit, bilişsel bozukluklar, davranış değişiklikleri ve çeşitli psikiyatrik hastalıklarla ilişkileri özetlenmiştir. Ayrıca kan-beyin bariyerinin bozulması, mikroglia ve astrosit aktivasyonu, sitokin aracılı kronik nöroinflamasyon, bağırsak-beyin ekseni ve nörotransmitter metabolizmasındaki değişiklikler gibi temel patofizyolojik mekanizmalar güncel bilgiler doğrultusunda tartışılmıştır. Mevcut kanıtlar, bazı paraziter enfeksiyonların nöropsikiyatrik hastalıklarla ilişkili olabileceğini desteklemekle birlikte, bu ilişkinin çoğu durumda nedensellik düzeyinde kanıtlanamadığını göstermektedir. Konunun daha iyi anlaşılabilmesi için geniş örneklemli, prospektif ve multidisipliner çalışmalara gereksinim bulunmaktadır.

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Cite This Article

Şimşek, P., Beytekin, H. K., Doğan, O., Sezak, N., Diniz, G. (2026). SILENT INVADERS OF THE BRAIN: NEUROIMMUNOLOGICAL MECHANISMS, NEUROLOGICAL AND PSYCHIATRIC EFFECTS OF PARASITIC INFECTIONS. İzmir Tıp Fakültesi Dergisi, Cilt: 5 Sayı: 3, 227–237. https://doi.org/10.57221/izmirtip.1980711

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