Ocular tuberculosis (OTB) encompasses all forms of intra- and extra-ocular inflammation associated with Mycobacterium tuberculosis (Mtb) infection. However, the organism is rarely found in ocular fluid samples of diseased eyes, rendering the pathomechanisms of the disease unclear. This confounds clinical decision-making in diagnosis and treatment of OTB. Here, we critically review existing human and animal data related to ocular inflammation and TB pathogenesis to unravel likely pathomechanisms of OTB. Broadly there appear to be two fundamental mechanisms that may underlie the development of TB-associated ocular inflammation: a. inflammatory response to live/replicating Mtb in the eye, and b. immune mediated ocular inflammation induced by non-viable Mtb or its components in the eye. This distinction is significant as in direct Mtb-driven mechanisms, diagnosis and treatment would be aimed at detection of Mtb-infection and its elimination; while indirect mechanisms would primarily require anti-inflammatory therapy with adjunctive anti-TB therapy. Further, we discuss how that most clinical phenotypes of OTB likely represent a combination of both mechanisms, with one being predominant than the other.

中文翻译：

---

眼结核的发病机制：新的观察和未来的方向

眼结核 (OTB) 包括与结核分枝杆菌 (Mtb) 感染相关的所有形式的眼内和眼外炎症。然而，在患病眼睛的眼液样本中很少发现这种微生物，使得该疾病的发病机制尚不清楚。这混淆了 OTB 诊断和治疗的临床决策。在这里，我们批判性地审查了与眼部炎症和 TB 发病机制相关的现有人类和动物数据，以揭示 OTB 的可能发病机制。从广义上讲，似乎有两种基本机制可能是 TB 相关眼部炎症发展的基础： a．对眼睛中活的/复制的 Mtb 的炎症反应，和 b. 由非活性 Mtb 或其在眼睛中的成分引起的免疫介导的眼部炎症。这种区别很重要，因为在直接 Mtb 驱动机制中，诊断和治疗旨在检测 Mtb 感染并消除；而间接机制主要需要抗炎治疗和辅助抗结核治疗。此外，我们讨论了 OTB 的大多数临床表型如何可能代表两种机制的组合，其中一种机制比另一种机制占主导地位。