Purpose

To describe the association between Sars-CoV-2 infection and small fiber neuropathy in the cornea identified by in vivo corneal confocal microscopy.

Methods

Twenty-three patients who had overcome COVID-19 were recruited to this observational retrospective study. Forty-six uninfected volunteers were also recruited and studied as a control group. All subjects were examined under in vivo confocal microscopy to obtain images of corneal subbasal nerve fibers in order to study the presence of neuroma-like structures, axonal beadings and dendritic cells. The Ocular Surface Disease Index (OSDI) questionnaire and Schirmer tear test were used as indicators of Dry Eye Disease (DED) and ocular surface pathology.

Results

Twenty-one patients (91.31%) presented alterations of the corneal subbasal plexus and corneal tissue consistent with small fiber neuropathy. Images from healthy subjects did not indicate significant nerve fiber or corneal tissue damage. Eight patients reported increased sensations of ocular dryness after COVID-19 infection and had positive DED indicators. Beaded axons were found in 82.60% of cases, mainly in patients reporting ocular irritation symptoms. Neuroma-like images were found in 65.22% patients, more frequently in those with OSDI scores >13. Dendritic cells were found in 69.56% of patients and were more frequent in younger asymptomatic patients. The presence of morphological alterations in patients up to 10 months after recovering from Sars-CoV-2 infection points to the chronic nature of the neuropathy.

Conclusions

Sars-CoV-2 infection may be inducing small fiber neuropathy in the ocular surface, sharing symptomatology and morphological landmarks with DED and diabetic neuropathy.

中文翻译：

---

Covid-19患者角膜小纤维神经病变与眼表疾病的发生有关

目的

描述 Sars-CoV-2 感染与通过体内角膜共聚焦显微镜确定的角膜小纤维神经病变之间的关联。

方法

这项观察性回顾性研究招募了 23 名战胜 COVID-19 的患者。还招募了 46 名未感染的志愿者作为对照组进行研究。在体内共聚焦显微镜下检查所有受试者以获得角膜基底神经纤维的图像，以研究神经瘤样结构、轴突串珠和树突细胞的存在。眼表疾病指数 (OSDI) 问卷和 Schirmer 泪液试验被用作干眼病 (DED) 和眼表病理学的指标。

结果

21 名患者 (91.31%) 表现出与小纤维神经病变一致的角膜基底丛和角膜组织的改变。来自健康受试者的图像没有显示出明显的神经纤维或角膜组织损伤。8 名患者报告 COVID-19 感染后眼部干燥感增加，并且 DED 指标呈阳性。在 82.60% 的病例中发现珠状轴突，主要是在报告眼部刺激症状的患者中。在 65.22% 的患者中发现神经瘤样图像，在 OSDI 评分 > 13 的患者中更常见。在 69.56% 的患者中发现了树突状细胞，并且在较年轻的无症状患者中更为常见。从 Sars-CoV-2 感染恢复后长达 10 个月的患者存在形态学改变，这表明神经病变具有慢性性质。

结论

Sars-CoV-2 感染可能会诱发眼表小纤维神经病变，与 DED 和糖尿病性神经病变具有相同的症状和形态学标志。