Leucoderma and Vitiligo: Are there differences between these conditions?

Leucoderma is a term derived from the ancient Greek leukós, meaning white, and dérma, referring to the skin. The etymology of this term allows us to understand that it is related to a white discolouration of the skin. According to the dictionary of the National Academy of Pharmacy, leucoderma is defined as follows: "Hypopigmentation or depigmentation of areas of the epidermis due to a deficiency or absence of melanin. It can be congenital, as in albinism, or acquired, for example in leprosy, psoriasis, syphilis, vitiligo or the scar tissue of a wound."

Vitiligo is a specific form of leucoderma characterised by a selective loss of melanocytes.

There are several types of leucoderma, which can result from various causes. Leucoderma can thus be the consequence of a lack of melanin pigment, following a decrease in the number of melanocytes or a defect in the synthesis or transfer of melanin, localised vasoconstriction, a deposit of white substance such as cutaneous calcification for example, tension exerted on the epidermis, by a cyst wall notably, a skin infarction such as in white atrophy or Degos disease or even a keratosis as in warts or molluscum contagiosum. Leucodermas can be diffuse or circumscribed. Based on this criterion and the age at which they appear, it is possible to differentiate them and determine if it is a case of vitiligo, as shown by the decision tree below.