Clostridium perfringens type D epsilon toxin (EXT) causes an important neurologic disorder of sheep, goats and, rarely, cattle. The disease can occur in peracute, acute, subacute, and chronic forms. High circulating levels of ETX produce vasculocentric brain lesions, in which microvascular endothelial injury results in diagnostically useful perivascular and intramural extravasations of plasma protein, especially in sheep, and less frequently in goats. With lower toxin doses, a more protracted clinical course tends to occur, particularly in sheep, leading to focal, bilaterally symmetrical, necrotic foci in certain brain regions. Although these morphologic features usually permit the diagnostic pathologist to make a definitive etiologic diagnosis, there are many aspects of the pathogenesis of these cerebral lesions that are not completely understood. ETX has also been shown to produce microvascular damage in the retina of rats, resulting in severe, diffuse vasogenic edema, similar to that found in brains exposed to this neurotoxin. The pathoclisis and vascular theories offer alternative explanations of the differential susceptibility of different brain regions to the same neurotoxic insult.

中文翻译：

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D型产气荚膜梭状芽胞杆菌ε毒素产生的脑和眼损伤的发病机制和诊断特征。

D型产气荚膜梭菌epsilon毒素（EXT）引起绵羊，山羊，很少有牛的重要神经系统疾病。该疾病可以以急性，急性，亚急性和慢性形式发生。ETX的高循环水平会产生以血管为中心的脑部病变，其中微血管内皮损伤会导致血浆蛋白的诊断性有用的血管周围和壁内渗出，尤其是在绵羊中，而在山羊中则较少。使用较低的毒素剂量，往往会出现更持久的临床过程，尤其是在绵羊中，导致某些大脑区域出现局灶性，两侧对称的坏死灶。尽管这些形态特征通常使诊断病理学家能够做出明确的病因诊断，但是这些脑部病变的发病机理有很多方面尚未完全了解。还已经显示，ETX会在大鼠视网膜中产生微血管损伤，导致严重的弥散性血管源性水肿，类似于暴露于这种神经毒素的大脑中的情况。病理和血管理论为不同的大脑区域对同一神经毒性损伤的敏感性差异提供了另一种解释。