Troubles Hyperpigmentaires chez les enfants

Pigmentary disorders are frequent in children and can result in significant psychosocial problems. Hyperpigmentary disorders can be classified into melanocytes problems (epidermal, dermal) and neurocutaneous disorders presenting with pigmentation problems. Giant congenital nevus carries a low risk of malignant transformation (melanoma) but it is important to exclude cutaneous neuromelanosis in high risk patients. Malignant lentiginosis…

Synthèse de la Mélanine et ses perturbations

Melanin is produced by mature melanocytes. The biosynthesis of melanin is a complex which implicateds numerous enzymes which include tyrosinase, TRP1, TRP2…Genetic disturbances of these enzymes can result in a pigmentary dilution which translates clinically with depigmentation as is seen for example in oculocutaneous albinism. The production of melanin is done within melanocytes in organelles…

Synthèse de la Mélanine et ses perturbations

Melanin is produced by mature melanocytes. The biosynthesis of melanin is a complex which implicateds numerous enzymes which include tyrosinase, TRP1, TRP2…Genetic disturbances of these enzymes can result in a pigmentary dilution which translates clinically with depigmentation as is seen for example in oculocutaneous albinism. The production of melanin is done within melanocytes in organelles…

Le rôle des Kératinocytes dans les troubles de la pigmentation

From the extremities of dendritic melanocytes, melanosomes are transfered to the neighbouring  keratinocytes. However, the mechanisms  implicated in this transfer are not well understood but involve an intimate contact between a melanocyte and a keratinocyte (in the epidermis). This in turn implies the presence of cell membrane proteins. The incapacity to do this explains the…

Le rôle des Kératinocytes dans les troubles de la pigmentation

From the extremities of dendritic melanocytes, melanosomes are transfered to the neighbouring  keratinocytes. However, the mechanisms  implicated in this transfer are not well understood but involve an intimate contact between a melanocyte and a keratinocyte (in the epidermis). This in turn implies the presence of cell membrane proteins. The incapacity to do this explains the…

Acide Tranéxamique en prise orale pour le traitement du melasma (chloasma, masque de grossesse): un résumé

Oral tranexamic acid taken orally is effective in the treatment of melasma (chloasma, pregnancy mask) refractory to topical combination treatment. These results are supported by evidence from previous studies frm Japan and South Korea. Tranexamic Acid (trans-4-aminomethylcyclohexanecarboxylic acid) is an anti-fibrinolytic agent which inhibits the activation of plasminogen by reversible blockade of lysine-binding molecules on…

Melasma (Chloasma, Masque de Grossesse): Comment le traiter ?

One of the reasons to this therapeutical frustration is due to the lack of understanding of the pathogenesis of melasma (chloasma, pregnancy mask). Although triggering factors (ultraviolet light, pregnancy, oral contraceptives) and immunohistochemical properties of melasma are well known, molecular and genetic mechanisms which are involved a poorly understood. Scientific Consensus says the following about…