The SARS-CoV-2 virus has the potential to adhere to the lacrimal gland in infected patients, making them susceptible to chronic bilateral dacryoadenitis, according to a case-control study published in JAMA Ophthalmology.
The retrospective case-control study was designed to examine the expression of SARS-CoV-2 nucleocapsid protein and ACE2 in the lacrimal gland tissues of a 35-year-old Japanese woman with COVID-19 who had lacrimal gland enlargements for 6 months with chronic bilateral dacryoadenitis (case), and a 43-year-old Japanese woman without COVID-19 but with idiopathic chronic bilateral dacryoadenitis (control). The main outcomes and measures were: Histopathology and immunohistochemistry with anti–SARS-CoV-2 nucleocapsid protein and ACE2 in the lacrimal glands.
Researchers found that the histopathologic findings for the patient with COVID-19 had marked inflammatory cell infiltration, lymphoid follicles, and germinal center formation in the lacrimal gland.
“The inflammation was mainly made up of lymphocytes and plasma cells with several polymorphonuclear leukocytes, where the lacrimal glands were atrophic. Of note, a number of lacrimal gland ducts markedly contained eosinophilic materials in the lumens, which indicated glandular damage. Immunoreactivity for SARS-CoV-2 nucleocapsid protein was noted in the inflammatory cells around the lacrimal gland ductal epithelia,” the investigators report. They also found strong ACE2 expression in the lacrimal gland.
In the patient who did not have COVID-19, her lacrimal gland had marked inflammation but no eosinophilic material deposits in the ductal lumens. “SARS-CoV-2 nucleocapsid protein immunoreactivity was not observed, whereas ACE2 was expressed in the lacrimal glands,” according to the study.
The study’s main limitation was that analysis by transmission electron microscopy and cryoelectron microscopy was unavailable.
Kase S, Ishida S. COVID-19-related chronic bilateral dacryoadenitis: a clinicopathological study. JAMA Ophthalmol. Published online February 17, 2022. doi:10.1001/jamaophthalmol.2021.6364.