SUMMARY A clinical study of vernal keratoconjunctivitis in black children in Southern Africa was conducted to report on the peculiar, predominantly limbal form of the disease, and to test its response to therapy. Pigmented and thickened limbal conjunctiva gave the disease its typical appearance. In severe cases these lesions were encroaching on to the cornea and threatened sight. Placebo had no effect on the course of the disease. Topical steroids and sodium cromoglycate were equally effective. A combination of steroids and SCG proved particularly effective in treating severe cases, indicating a possible synergistic effect of the 2 drugs.Vernal keratoconjunctivitis (VKC) is a recurrent external ocular disease of unknown aetiology, often characterised by seasonal exacerbations. The patient, usually in the first or second decade of life, usually a male, complains of itching, grittiness, watering, and photophobia. Diagnostic signs include a thick, stringy, mucous discharge, a giant 'cobblestone' papillary reaction of the upper tarsal conjunctiva, papillary changes of the bulbar conjunctiva, especially at the upper limbus, and corneal pathology, ranging from superficial punctate keratitis (SPK) through ulceration and plaque formation.Many patients have a personal or family history of atophy, and the disease has been characterised as a form of type I (immediate) hypersensitivity.' Therapy has centred about the use of topical corticosteroids,2 but there have been many encouraging recent reports of the use of sodium cromoglycate (SCG) eye drops in VKC,3-7 both to control the acute manifestations of the disease and to reduce the patients' dependence on the use of corticosteroids, which carry with them the attendant risks of infections and glaucoma.Most patients studied, usually of Western European background, display the typical picture of VKC as described above. But some have a rather different, though equally striking picture. They show a circumcorneal, pigmented limbal thickening, sometimes encroaching on to the cornea, practically or totally to the exclusion of other findings (see Figs.
