Fibrosis May Cause Aqueous Tear Deficiency in Stevens-Johnson Syndrome

Fibrosis in the periductal conjunctiva, not inflammation in the lacrimal glands, causes the severe aqueous tear deficiency in Stevens-Johnson syndrome (SJS), a study published in Ophthalmology suggests.¹ In fact, the study indicated, when patients experience severe SJS with no aqueous secretion, their lacrimal glands’ orbital lobes have normal acinar structure, secretory activity, and myoepithelial cells.¹

Doctors may be able to treat the fibrosis that patients experience, instead of needing to rejuvenate the entire lacrimal gland, the researchers say.¹

In the study, researchers biopsied the orbital lobe of six lacrimal glands from five patients with SJS who had a mean age of 33 years. Each gland had chronic ocular sequelae and no tear secretion. The team compared these glands to lacrimal glands from two body donors who did not have recent trauma or infections as well as tissue from orbital B-cell lymphoma (CD20). They then stained the 4μm serial sections of the tissue biopsies with hematoxylin-eosin, lactoferrin, lysozyme, S-100, smooth muscle actin alpha subunit (SMA), and CD20. 

They saw that five of the biopsies had maintained their acinar morphology and did not show acinar atrophy or fibrosis, and the sixth only showed that ductal tissue, not an acinar component, was present.¹ Myoepithelial cells with SMA expression were in most of the acini in all samples. Even though investigators had demonstrated that inflammation and scarring in the lamina propria causes ductal dilatation and proliferation, researchers did not see those ductal changes in the SJS glands’ interlobular ducts.¹ 

The researchers said further research might determine treatments for preventing and reversing the fibrosis in the superotemporal fornix.¹ The report adds to a 2019 study’s findings, which indicated that aqueous tear deficiency in SJS could be from fibrosis in the periductal conjunctiva, not primary inflammatory damage to the lacrimal gland.²

References

1. Singh S, Mishra DK, Shanbhag S, et. al. Lacrimal Gland Involvement in Severe Dry Eyes Following Stevens-Johnson syndrome. Published online August 21, 2020, Ophthalmology. doi: https://doi.org/10.1016/j.ophtha.2020.08.016.

2. Singh S, Narang P, Vashist U, et al. Histomorphological Changes in Lachrymal Glands of Patients With Chronic Stevens–Johnson Syndrome. Cornea. 2019;38(9):e39-e40 doi:10.1097/ICO.0000000000002037.