Alteration in inflammatory mediators in seriously eye-injured war veterans, long-term after sulfur mustard exposure

Sulfur mustard (SM) exposure produces extensive systemic and ocular adverse effects on the victims. One of the most important effects is immunological insults that can lead to other organ damages, including the eyes.

In this descriptive study, 128 SM-exposed veterans with severe eye injury were compared with 31 healthy controls. Tear levels of tumor necrosis factor (TNF)-α and serum concentrations of interleukin (IL)-1α, IL-1β, IL1Ra, IL-6, TNF-α, granulocyte-macrophage colony-stimulating factor (GM-CSF), and Fas Ligand (FasL) were compared between the two groups.

Meibomian gland dysfunction (MGD); tear breakup time (TBUT < 10″); and conjunctival, limbal, and corneal abnormalities were more frequent among the cases (MS-exposed veterans) than the controls. Ocular involvement was mild in 14.8%, moderate in 24.2%, and severe in 60.9% of the cases. Serum levels of IL-1α and FasL were significantly higher among the cases than among the controls (P < 0.001 and P = 0.037, respectively). Also, a significant decrease was observed in serum and tear levels of TNF-α in the cases as compared with controls (P < 0.001, P < 0.001, respectively). Serum levels of FasL were significantly higher in cases with severe ocular involvement than in the controls (P = 0.03). Nonetheless, serum levels of IL-1β, IL-1Ra, IL-1α/IL-1Ra, and IL-6 were not significantly different between the two groups.

Serum levels of IL-1α and FasL may cause different ocular surface abnormalities in SM-exposed patients. Lower tear TNF-α concentration may be due to lower serum levels of this cytokine in these patients.