Limbal vernal keratoconjunctivitis: clinical characteristics and immunoglobulin E expression compared with palpebral vernal.

Limbal and palpebral vernal keratoconjunctivitis (VKC) are usually considered to be different expressions of the same disease. This single centre population of 120 patients with VKC had 32 patients with limbal VKC, 54 with palpebral VKC and 34 with mixed palpebral and limbal VKC. There were higher proportions of females (p = 0.015) blacks, Indians and Asians (p = 0.0001) in the limbal group and fewer limbal patients had other atopic diseases (p = 0.03). The age of presentation was similar for all groups; 87/112 (78 per cent) presenting before the age of 16. The follow-up period was shorter in the limbal VKC patients (p = 0.004) suggesting a shorter disease course. Only one limbal VKC patient developed corneal opacities compared to fifty (47 per cent) with palpebral or mixed VKC, 24 (27 per cent) of whom lost vision. Tear and serum levels of total IgE and specific IgE to the major inhalent allergens cat, house dust mite and grass pollen were compared in 17 patients with palpebral or mixed VKC and ten with limbal VKC; no statistically significant differences were shown. However the significant variations in sex, racial distribution and associated atopic disease suggest that limbal VKC may be a different disease from palpebral VKC although this is not expressed in terms of IgE production.