Expression of Tissue inhibitor of metalloproteinase in ocular Stevens-Johnson Syndrome: An Immunohistochemical Study
Abstract
Purpose
Tissue inhibitor of metalloproteinase-1 (TIMP-1) forms complexes with Matrix Metalloproteinases to inhibit tissue degradation and extracellular matrix (ECM) accumulation. Involvement of TIMP-1 in Stevens -Johnson syndrome (SJS) ocular pannus formation remains unexplored. Therefore, this study aims to evaluate the expression of TIMP-1 in SJS ocular sequelae patients.
Methods
Pannus tissues of 18 SJS patients excised during ocular surface reconstruction surgeries were collected. Clinical and histopathological parameters were examined. Immunohistochemistry (IHC) was performed on all cases for TIMP-1 and evaluated on the basis of epithelial/stromal staining intensity. Expression of TIMP-1 was statistically correlated with the histopathological and clinical parameters.
Results
Mean age was 25.6 ± 13.10 years. There was a male preponderance. Antipyretics (38%) were the most common cause of ocular SJS. Mean duration from onset of systemic episode to first presentation was 8.3 ± 6.2 years. Mean BCVA was 2.72 logMAR ± 0.47, mean Schirmer's value was 0.27 ± 1 mm. Epithelial hyperplasia was found histologically in 88.8% and stromal vascularization in 55%. Stromal fibrosis was indentified in 22%. TIMP-1 expression was found in pannus epithelium in 13 cases and in stroma in 15 cases. Epithelial TIMP-1 expression was statistically significant with epithelial hyperplasia, epithelial keratinization, squamous metaplasia, inflammation and stromal fibrosis (p < 0.05). Stromal TIMP-1 positivity correlated significantly with epithelial keratinization (p = 0.0134).
Conclusions
TIMP-1 protein expression correlated with the histopathological factors in ocular manifestations of SJS. This indicates TIMP-1's contribution in pannus formation which involves ECM modifications. This may help TIMP-1 to be considered as a possible therapeutic target in SJS.
