Correlation between lymphotoxin-α concentrations and conjunctival goblet cell density in dry eye patients

Abstract Purpose To explore the relationship between the tear lymphotoxin-α (LT-α) concentration, conjunctival goblet cell density (GCD) and ophthalmic parameters in dry eye patients and the value of the LT-α concentration and conjunctival GCD in diagnosing dry eye. Methods Prospective case‒control study. Seventy-eight dry eye patients and twenty normal subjects were recruited. After completing the China Dry Eye Questionnaire, all subjects were examined in sequence with slit-lamp microscopy, tear LT-α concentration analysis, tear meniscus height measurement, the Schirmer I test and the conjunctival GCD examination using confocal microscopy. Results The conjunctival GCD (54.70 (24.38–126.50) cells/mm 2 ) in the dry eye group was lower than that in the control group (125.80 (72.75–180.00) cells/mm 2 ) (P = 0.011). The LT-α concentration(0.17(0.05–1.18) ng/ml) in the dry eye group was lower than that in the control group(0.30(0.13–1.32) ng/ml) without statistical significance (P = 0.366). And the LT-α concentrations were positively correlated with the tear film breakup time (FBUT) ( r = 0.262, p < 0.01). When LT-α < 1.47 ng/ml (81.6% subjects fell in this range), conjunctival GCD was positively correlated with the LT-α concentration (β = 63.92, P = 0.004). The area under the ROC curve (AUC) of LT-α concentration in the diagnosis of dry eye was 0.5657, the cutoff value was 0.11 ng/ml, the sensitivity was 41.03%, and the specificity was 80.00%. The AUC of conjunctival GCD in the diagnosis of dry eye was 0.6993, the cutoff value was 67.90 cells/mm 2 , the sensitivity was 59.15%, and the specificity was 82.35%. Conclusion The LT-α concentration is valuable in evaluating conjunctival GCD and tear film stability. The value of evaluating the conjunctival GCD using confocal microscopy in dry eye diagnosis is worthy of attention.