The authors report a series of five markedly atopic patients in whom a severe sclerokeratitis developed within 1 to 4 weeks of keratoplasty. The onset was acute with discomfort, photophobia, hyperemia, and mucus production. This resulted in early loosening of sutures and was associated with microbial keratitis in two cases and graft rejection in one. The inflammatory reaction was controlled with high-dose oral steroids and did not recur when the treatment was terminated. Serum IgE levels were elevated in all these patients (range, 421-8434 kU/l). Binding of this IgE onto the surface of mast cells in the conjunctiva with subsequent degranulation may be involved in the pathogenesis of the induced inflammation. Principal recommendations include the use of interrupted sutures and early immunosuppression with high-dose oral steroids at the onset of this condition together with the control of risk factors for microbial keratitis.