Association of Sulfur Mustard-induced Ocular Problems with Serum and Blood Biochemical Parameters Changes

Background & objective: Many biochemical features of sulfur mustard (SM) intoxication remained unknown. So far, the direct association between biochemical parameter changes and ocular problems in patients exposed to SM is not evaluated.The current study aimed at evaluating the associations between the ocular findings in patients with SM intoxication and the changes of serum and blood biochemical parameters. Methods: In the current study, 372 patients exposed to SM and 128 matched controls were compared concerning the association between their ocular problems and biochemical parameters. Ocular problems include photophobia, ocular surface discomfort (OSD), etc. Biochemical parameters include uric acid, creatinine (Cr), hematocrit (HCT), total, direct and indirect bilirubin, high-density lipoproteins (HDL), alanine aminotransferase (ALT), calcium (Ca), fasting blood sugar (FBS), mean corpuscular hemoglobin concentration (MCHC), etc. Results: The SM-exposed group with photophobia, OSD, tearing, blurred vision, abnormal tear status, and slit-lamp findings had significantly higher mean serum and blood levels of uric acid, Cr, HCT, and total and indirect bilirubin than the controls. The SM-exposed group with photophobia, tearing, ocular pain, blurred vision, bulbar conjunctival and limbal abnormalities had significantly higher mean serum and blood levels of HDL, ALT, Ca, FBS, MCHC, and HDL, indirect and total bilirubin, compared to the control group. Conclusion: The association of photophobia with uric acid, OSD and tearing with Cr, photophobia with HDL, ocular pain with Ca, and blurred vision with FBS may be explained for their known ocular effects in the SM-exposed subjects. SM-induced biochemical changes may intensify the ocular problems induced by the direct effects of SM.