Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Oct 12;13(20):3188.
doi: 10.3390/diagnostics13203188.

Neuroinflammatory Findings of Corneal Confocal Microscopy in Long COVID-19 Patients, 2 Years after Acute SARS-CoV-2 Infection

Pilar Cañadas  1 , Leonela Gonzalez-Vides  1   2 , Marta Alberquilla García-Velasco  1 , Pedro Arriola  3 , Noemí Guemes-Villahoz  3 , Jose Luis Hernández-Verdejo  1
Affiliations

Neuroinflammatory Findings of Corneal Confocal Microscopy in Long COVID-19 Patients, 2 Years after Acute SARS-CoV-2 Infection

Pilar Cañadas et al. Diagnostics (Basel). .

Abstract

Objective: To describe corneal confocal microscopy findings in patients with long COVID-19 with persistent symptoms over 20 months after SARS-CoV-2 infection.

Design: A descriptive cross-sectional study that included a total of 88 patients; 60 patients with Long COVID-19 and 28 controls. Long COVID-19 diagnosis was established according to the World Health Organization criteria. Corneal confocal microscopy using a Heidelberg Retina Tomograph II (Heidelberg Engineering, Heidelberg, Germany) was performed to evaluate sub-basal nerve plexus morphology (corneal nerve fiber density, nerve fiber length, nerve branch density, nerve fiber total branch density, nerve fiber area, and nerve fiber width). Dendritic cell density and area, along with microneuromas and other morphological changes of the nerve fibers were recorded.

Results: Long COVID-19 patients presented with reduced corneal nerve density and branch density as well as shorter corneal nerves compared to the control group. Additionally, Long COVID-19 patients showed an increased density of dendritic cells also with a greater area than that found in the control group of patients without systemic diseases. Microneuromas were detected in 15% of Long COVID-19 patients.

Conclusions: Long COVID-19 patients exhibited altered corneal nerve parameters and increased DC density over 20 months after acute SARS-CoV-2 infection. These findings are consistent with a neuroinflammatory condition hypothesized to be present in patients with Long COVID-19, highlighting the potential role of corneal confocal microscopy as a promising noninvasive technique for the study of patients with Long COVID-19.

Keywords: COVID-19; Long-COVID; corneal confocal microscopy; corneal nerve plexus; dendritic cells.

PubMed Disclaimer

Conflict of interest statement

All The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Dendritic cell count.
Figure 2
Figure 2
Dendritic cell area analysis.
Figure 3
Figure 3
Corneal sub-basal nerve plexus with visible microneuromas marked by with arrows.
Figure 4
Figure 4
Representative CCM images: (A) Corneal nerve plexus in control patient. (B) Corneal nerve plexus in Long COVID-19 patients. (C) Dendritic cell representative image in Long COVID-19 patient.
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Mao L., Jin H., Wang M., Hu Y., Chen S., He Q., Chang J., Hong C., Zhou Y., Wang D., et al. Neurologic Manifestations of Hospitalized Patients with Coronavirus Disease 2019 in Wuhan, China. JAMA Neurol. 2020;77:683–690. doi: 10.1001/jamaneurol.2020.1127. - DOI - PMC - PubMed
    1. Soriano J.B., Murthy S., Marshall J.C., Relan P., Diaz J.V. A clinical case definition of post-COVID-19 condition by a Delphi consensus. Lancet Infect. Dis. 2022;22:e102–e107. doi: 10.1016/S1473-3099(21)00703-9. - DOI - PMC - PubMed
    1. Nasserie T., Hittle M., Goodman S.N. Assessment of the Frequency and Variety of Persistent Symptoms Among Patients with COVID-19: A Systematic Review. JAMA Netw. Open. 2021;4:e2111417. doi: 10.1001/jamanetworkopen.2021.11417. - DOI - PMC - PubMed
    1. Delbressine J.M., Machado F.V.C., Goërtz Y.M.J., Van Herck M., Meys R., Houben-Wilke S., Burtin C., Franssen F.M.E., Spies Y., Vijlbrief H., et al. The Impact of Post-COVID-19 Syndrome on Self-Reported Physical Activity. Int. J. Environ. Res. Public Health. 2021;18:6017. doi: 10.3390/ijerph18116017. - DOI - PMC - PubMed
    1. Malik P., Patel K., Pinto C., Jaiswal R., Tirupathi R., Pillai S., Patel U. Post-acute COVID-19 syndrome (PCS) and health-related quality of life (HRQoL)-A systematic review and meta-analysis. J. Med. Virol. 2022;94:253–262. doi: 10.1002/jmv.27309. - DOI - PMC - PubMed

LinkOut - more resources