Matrix metalloproteinase 9 is associated with conjunctival microbiota culture positivity in Korean patients with chronic Stevens-Johnson syndrome

BACKGROUND: Stevens-Johnson syndrome (SJS) is an abnormal immune-response causing extensive exfoliation of the mucocutaneous tissue including conjunctiva. While several factors are associated with the alteration of conjunctival microbiota, the conjunctiva of SJS patients are found to harbor a different microbiota compared to healthy subjects. We investigated the conjunctival microbiota of Korean SJS patients, and identified factors associated with the conjunctival microbiota and its positive culture. METHODS: Medical records were retrospectively reviewed in 30 chronic SJS patients who had undergone conjunctival swab culture sampling. Demographic factors, chronic ocular surface complications score (COCS), tear break-up time (TBUT), tear secretion, tear matrix metalloproteinase 9 (MMP9), and results of conjunctival swab culture were assessed. RESULTS: Positive culture was seen in 58.1%. Gram positive bacteria was most commonly isolated, among which Coagulase-negative Staphylococci (45.5%) and Corynebacterium species (40.9%) were predominantly observed. Tear MMP9 positivity was observed significantly more in the positive culture group (100%) compared to the negative culture group (70%) (P = 0.041). Topical cyclosporine and corticosteroid were not associated with repetitive positive cultures. No significant differences in COCS, TBUT, and tear secretion were found between culture-positive and culture-negative groups. CONCLUSION: Our study suggests that tear MMP9 positivity may be related with the presence of an abnormal ocular surface microbiota in chronic SJS patients.