Posters

Keratoconus: an inflammatory disorder?

Poster Details

First Author: A.Tello COLOMBIA

Co Author(s):    V. Galvis   T. Sherwin   J. Merayo   R. Barrera   A. Acera        

Abstract Details

Purpose:

Perform a literature review of published biochemical changes in keratoconus that would support that this could be, at least in part, an inflammatory condition.

Setting:

Centro Oftalmologico Virgilio Galvis, Floridablanca, Colombia. Faculty of Health Sciences. Universidad Autonoma de Bucaramanga, Floridablanca, Colombia. Department of Ophthalmology. New Zealand National Eye Centre. Faculty of Medical and Health Sciences. University of Auckland, Auckland. New Zealand. Instituto Oftalmologico Fernandez-Vega, Oviedo, Spain. Bioftalmik Applied Research, Derio, Spain.

Methods:

For this review, we searched PubMed database for articles related to keratoconus using the terms “keratoconus”, "corneal ectasia" and "pellucid marginal degeneration" combined with the terms “aetiology”, “pathophysiology”, "antioxidants", "extracellular matrix enzymes", "oxidative stress" and “inflammation”. Papers published up to December 2014 were included. All articles and their list of references were carefully reviewed. In total we found 342 articles, but finally we selected 167 articles. Additionally we used a web search engine (Google) to find other publications (books or chapters) on the topic. We reviewed four chapters of two recently published books.

Results:

It has been suggested that IL-1, TNF-α, TGF, IL-6, IL-8 and PDGF, might regulate a protease cascade involving the plasmin system, cyclooxygenase and metalloproteinases, which eventually would lead to the observed changes in the extracellular matrix of the cornea with keratoconus. The majority of studies in the tears of patients with keratoconus have found increased levels of IL-6, TNF-α and MMP-9. In ocular rosacea, IL-1α and MMP-9 have been reported to be significantly elevated, and cases of inferior corneal thinning have been reported. Eye rubbing recently has been also shown to increase the levels of MMP-13, IL-6 and TNF- α.

Conclusions:

Increasing evidence supports the fact that thinning and ectasia of the cornea are related to a degraded extracellular matrix involving inflammatory events (mainly increased levels of MMP-9, IL-6 and TNF-α) and increased oxidative stress. The already demonstrated involvement of inflammatory mediators in the pathophysiology of keratoconus might make that keeping it classified as a non-inflammatory condition may be no longer adequate. Although the condition does not meet all the classic criteria for an inflammatory disease, published biochemical changes in keratoconus seem to support that this could be, at least in part, an inflammatory condition.

Financial Disclosure:

NONE