A clinicohistopathological study was made of 19 cases with different types of congenital hyperkeratoses in Kenyan Africans. Gradations were found between the bullous and nonbullous types of congenital ichthyosiform erythroderma of Brocq (CIEB). This led to the conclusion that there exists a spectrum of variants between these two forms of the disease. Ichthyosis hystrix and congenital ichthyosiform erythroderma showed no essential histological differences and should be considered as generalized and localized forms of the same condition.
Verhagen ARHB, Koten JW. Congenital Hyperkeratoses in Africans. Arch Dermatol. 1968;98(4):364-371. doi:10.1001/archderm.1968.01610160038007