Ocular Allergy as a Risk Factor for Dry Eye in Adults and Children

Edoardo Villani; Giovanni Rabbiolo; Paolo Nucci


Curr Opin Allergy Clin Immunol. 2018;18(5):398-403. 

In This Article

Abstract and Introduction


Purpose of review: To provide an overview of the pathogenic mechanisms underlying the correlation between ocular allergy and dry eye disease (DED), highlighting how the first condition may be a risk factor for the second one.

Recent findings: Recent advances in our comprehension of the pathogenesis of ocular allergy and DED allow identifying several pathways of interaction between these two conditions. A growing body of evidence supports the role of ocular allergy as a risk factor for DED. Ocular allergy, particularly the severe forms of keratoconjunctivitis, can impact on different key mechanisms of the DED vicious cycle, including tear film instability, ocular surface inflammation and damage, and neurosensory abnormalities.

Summary: Ocular allergy and DED are two common, relevant, symptomatic, not mutually exclusive conditions affecting the ocular surface. They share some clinical and biochemical features. To better understand the complex interactions between these two conditions, it's essential to consider the very wide spectrum of clinical conditions included in the term ocular allergy and the still largely unexplored peculiarities of the pediatric ocular surface physio-pathology and DED.


In the daily clinical practice ocular allergy and dry eye disease (DED) are common and growing healthcare problems, with a significant negative impact on quality of life and productivity.[1,2]

Epidemiological studies, made difficult by heterogeneity and lack of standardization of diseases' definitions and diagnostic algorithms,[3,4] report prevalence ranges in the general population of 10–30% and 5–50%, respectively, for ocular allergy and DED.[1,2] However, although ocular allergy seems to affect more commonly children and adolescents,[1,5] DED prevalence increases with age.[2]

Ocular allergy and DED are different clinical entities affecting the ocular surface but their clinical manifestations include partly overlapping signs and symptoms.[6] The coexistence of these two conditions, hypothesized more than 20 years ago,[7] has been confirmed to be a common circumstance by large cross-sectional studies.[6] Several studies tried to investigate the relationship between ocular allergy and DED, suggesting that the first one can predispose to the second one, and the Tear Film and Ocular Surface Society Dry Eye WorkShop II (TFOS DEWS II) recently included Allergic Conjunctivitis among the 'probable' (supported by suggestive evidence, implying the existence of either inconclusive information from peer-reviewed publications or inconclusive or limited information but either not published or published somewhere other than in a peer-reviewed journal) risk factors for DED.[2]

The current article is aimed to provide a critical revision of new insights into the pathogenetic mechanisms of DED and how they can be affected by ocular allergy.