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Dr. A.R. Verhagen, St. Joseph Hospital, Aalsterweg, Eindhoven (The Netherlands) Dear Sir, In 1964 [1] and 1966 [2], Shrank described ‘keratosis circumscripta’ as a separate entity in Nigeria. Soyinka andLaja [3] suggest that it is a variant of psoriasis. Between 1965 and 1974 we saw a number of patients who fitted Shrank’s description in Kenya, East Africa. About 10 cases were studied and observed in systematic fashion, including biopsy and prolonged follow-up, as we planned to confirm Shrank’s observations. Only the localisation and sharp margins may have somewhat resembled psoriasis. Otherwise, the aspect, notably the type of hyperkeratosis, was totally different. There were deep furrows resembling lichenification or even some types of congenital ichthyosis, but no profuse silvery white scales with the wax candle phenomenon. In the histological picture, there were hardly any dermal abnormalities, notably in the papillae, or Munro’s abscesses. The age distribution showed, as suggested by Shrank, a disease of children and adolescents. We could add a prolonged follow-up to Shrank’s observations: The patches were remarkably stable over many months or years, they hardly responded to cortico-steroids, as suggested by Soyinka andLaja [3], and we never saw a transition into classical psoriasis. We reported in 1967 [4] that psoriasis was by no means rare in tropical Africa and we confirmed this repeatedly [5, 6]. However, like Shrank, we hardly ‘considered psoriasis in our deliberations’ [3] in our cases of ‘keratosis circumscripta’; there was hardly any resemblance. We conclude that Shrank [1, 2] and Soyinka andLaja [3] have described different groups of patients and that ‘keratosis circumscripta’ may be found elsewhere in Africa. However, we agree with Soyinka andLaja [3] that we found keratosis circumscripta in several tribes belonging to widely different linguistic groups and that the predominance of Yoruba’s in Ibadan [1 ‚ 2] might simply reflect the composition of the local population. References Shrank, A.B.: Keratosis circumscripta. 1st Int. Congr. Trop. Dermatology, Naples 1964. Shrank, A.B.: Keratosis circumscripta. Archs Derm. 93: 408-410 (1966). Soyinka, F. and Laja, A.O.: Keratosis circumscripta. A distinct dermatological entity or a variant of psoriasis? Dermatologica 156: 341-350 (1978). Verhagen, A.R.H.B. and Koten, J.W.: Psoriasis in Kenya. Archs Derm. 96: 39-41 (1967). Letters to the Editor 183 Verhagen, A.R.H.B.; Koten, J.W.; Chaddah, V.K., and Patel, R.I.: Skin diseases in Kenya. Archs Derm. 98: 577-586 (1968). Verhagen, A.R.H.B.: Dermatoses in dark-skinned people, a pictorial documentation in 8 parts (Ciba-Geigy Ltd., Basle 1976).