Comparison of Tear Functions and Ocular Surface Findings between Children and Adults with Atopic Dermatitis.

Abstract

Abstract: : Purpose:Atopic keratoconjunctivitis (AKC) associated with Atopic Dermatitis(AD) often has a chronic course and is refractory to treatment. We previously reported that the ocular surface disorder in AD was characterized by conjunctival squamous metaplasia and goblet cell loss. This time we studied the differences in tear functions and ocular surface health status between children and adults with AD. Methods:We recruited 20 eyes of 10 children, 16 eyes of 8 adult patients with AD starting during in infancy, and 18 eyes of 9 age and sex matched healthy subjects as controls.All patients had AKC. None of the patients or controls had any other ocular or systemic disease. All patients had the same treatment including topical antiallergics and steroids. All cases underwent corneal sensitivity measurements, tear clearance test, Schirmer test –1, BUT measurements, Rose–Bengal and fluorescein vital stainings, upper tarsal conjunctival impression and brush cytology (BC). Impression cytology (IC) specimens were evaluated by PAS and immunohistochemical staining employing Muc5AC antibodies. Cells from BC specimens obtained from upper tarsal conjunctiva were studied with Real Time PCR to assess the Muc5AC mRNA expression. The relation of activity and recurrences of AD to the study parameters was also looked for. Results:The mean corneal sensitivity, tear clearance, and BUT values were lower and vital staining scores were higher in AKC patients compared to controls (p<0.05). Schirmer test values were slightly lower in the patients than controls (p>0.05). IC showed significant keratinization and reduction of goblet cells with decreased mucin pick up as assessed by PAS and Muc5AC staining in eyes with AKC. Real Time PCR also showed decrease in Muc5AC expression in the patients. A comparison of adult AKC patients to children with AKC revealed the same trend in all examined parameters except Schirmer test–1 which showed a significant and a dramatic reduction in adult AKC patients. Activity and recurrences of skin disease had a significant correlation with deterioration of tear functions and ocular surface health as evidenced by the studied parameters. Conclusions:Tear functions and ocular surface health in AKC patients with AD seem to decline with duration and activity of skin disease suggesting follow up of such patients long after puberty and the need to study the histopathological changes in lacrimal gland in detail.

Keywords: cornea: tears/tear film/dry eye • conjunctivitis • cornea: clinical science