Keratoconus and Inflammatory Skin Conditions Share Connection

Atopic diseases and keratoconus may be linked via the mechanical effects of eye rubbing, which is common in atopic dermatitis because of pruritic. Over time, the repetitive trauma of rubbing can exacerbate corneal damage. Photo: Julie Song, OD. Click image to enlarge. Corneal ectasias and immune-mediated afflictions have recently been hypothesized to have some sort of relationship. In particular, dermatologic conditions with underlying inflammation may be a potential contributor to keratoconus (KC) development due to inflammation being pathogenically involved.To better elucidate any possible relationship, researchers from Baylor College of Medicine collected data from the TriNetX Global Collaborative Network—an aggregated electronic health records database spanning 19 countries that includes 165 million patients. Then, adults aged 18 to 40 who were diagnosed with each of the included inflammatory skin conditions (with no corneal disorder history) were matched 1:1 with controls for demographics and known risk factors of KC.The investigators of the paper, published in Cornea, found that, compared with controls, patients with atopic dermatitis displayed a 2.3-fold increase risk of KC development at five years; for the same time span, patients with psoriasis had a 2.0-fold increased risk, seborrheic dermatitis conferred a 1.6-fold increase, contact dermatitis with a 1.6-fold increase and urticaria also with a 1.6-fold increase of developing the ocular disease. Interestingly, rosacea did not exhibit any significant association with KC.The authors relay in their paper that several mechanisms may be responsible for the observed relationship between conditions affecting different organ systems. At the core is the factor of immune dysregulation and inflammation. Certain inflammatory cytokines—interleukin-1b, interleukin-6, interleukin-17 and tumor necrosis factor alpha—are all commonly found in KC patients’ tears and corneal tissue but are also implicated in the conditions of psoriasis, seborrheic dermatitis and contact dermatitis.Elevated cytokine levels promote local inflammation as well as disrupting collagen crosslinking, which is a critical process in providing structural stability to the cornea and skin, the authors explained in the journal article. In keratoconus, reduction in corneal crosslinking leads to corneal thinning and ectasia, while, with inflammatory skin conditions, elevated cytokines can impair collagen structure and function, resulting in a systemic impact. To illustrate this point, the authors use the example of allergic inflammation having been shown to destabilize crosslinked collagen structures in the cornea, emphasizing the potential for systemic inflammatory processes to weaken corneal integrity.In relation to patients with inflammatory dermatologic conditions, the authors suggest that, “with appropriate index of suspicion and increased awareness of populations at heightened risk for KC, it may be possible to diagnose patients with these conditions earlier in their disease course, potentially reducing complications associated with late-stage disease.”They further point out that “our findings also raise important questions about the role of systemic inflammation in KC pathogenesis and whether early identification and management of inflammatory skin conditions could have preventive implications.”Click here for the journal source. Muayad J, Madsen JA, Sontam TR, et al. Real-world analysis of inflammatory dermatologic conditions and their association with keratoconus. Cornea. 2025;00:1-6. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.