Eye involvement in a series of 94 young patients with congenital ichthyosis: importance of early ophthalmological referral.

Eye involvement in congenital ichthyosis, now reclassified as epidermal differentiation disorders (EDDs) is well recognized, but precise prevalence and risk factors remain unclear. Dry eye disease (72%) and meibomian gland dysfunction (62%) are highly prevalent. Ocular involvement varied by EDD subtype. Patients with STS-nonsyndromic EDD (nEDD) (formerly recessive X-linked ichthyosis) and KRT1/KRT10 nEDD (formerly keratinopathic ichthyosis) exhibited significantly fewer ocular findings, whereas those with severe involvement and syndromic forms showed higher rates of DED, MGD, and ectropion. In univariate analysis, age was the strongest predictor of DED. In multivariate modelling, EDD type, but not severity, remained associated with ocular involvement, while age showed a positive trend toward increasing risk over time. Causal inference analysis demonstrated a stepwise progression of eye disease: age-related MGD led to evaporative DED, which triggered conjunctival inflammation and keratopathy. Corneal opacities arose secondarily from chronic DED and exposure, and directly from ectropion. Astigmatism was strongly associated with DED and ectropion, likely due to progression of corneal surface irregularity. Importantly,this model suggests that ocular morbidity in EDD is not solely a function of severity, but reflects cumulative effects of time, eyelid changes, and tear film instability.
Dry eye disease appears pivotal, driving conjunctival injection, keratopathy, and corneal opacities. Early ophthalmologic referral is crucial to prevent irreversible visual impairment.