Diagnostic value of the café-au-lait spot in children.

The significance of the cafe-au-lait spot in the diagnosis of certain disorders of childhood is still not as widely appreciated as it should be, partly due to lack of information as to the normal incidence of such pigmentation, and partly to confusion over its relation to other forms of congenital pigmentation. The varieties of congenital melanin pigmentation of the skin consist of a number of separate entities superimposed upon the basic normal colour of the skin, depending on the racial and genetic endowment of the individual. Although these entities are clear cut and separate in form and histology, and irrespective of the basic colour of the skin, a small number may give rise to difficulty in differentiation from each other. These accessory pigmented areas include the various types of moles or melanotic naevi, mongolian spots, and caf&-au-lait spots. The various types of vitiligo also merit inclusion in this group, because there is often a distinct suggestion of hyperpigmentation at the border of the depigmented areas. Although these pigmentary changes are so universally present as to be regarded as normal, under certain circumstances they may indicate the coexistence of an underlying disease. This is particularly so with respect to the cafe-au-lait spot and, to a lesser degree, to the reverse phenomenon, vitiligo. Even in a very recent and comprehensive review of the pigment cell (Riley and Fortner, 1963), the cafe-au-lait spot has been largely ignored. Early recognition of the importance of the cafe-au-lait mark was probably obscured by the nineteenth century grouping of all congenital pigmented birth marks as 'pigmented naevi', but Marie and Bernard (1896) and Chauffard (1896) independently drew attention to the association of certain types of pigmentation of the skin with generalized neurofibromatosis of the type previously described in 1882 by von Recklinghausen. Since that time the significance of these observations has been amply confirmed and extended, but the condi-