Melasma Diagnosis

Melasma
Diagnosis
Any person of any race can be affected. However, it is more common in dark constiturtive types, the brown, Hispanics and Asians, from areas exposed to intense sunlight. Melasma is more common in women than in men. Women are affected in 90% of cases. When men are affected the same clinical and histological. Melasma is rare before puberty and more common in women during the reproductive period of life.
Patients may develop melasma after prolonged use of oral contraceptives and pregnancy. Intense or chronic exposure to sunlight worsens the condition and may precipitate melasma, but because of the insidious development of pigmentation often patients can not recognize the association.
Physical examination. Macular hyperpigmentation of melasma is bronze-brown color. Blue or black may be evident in patients with dermal melasma. Distribution is centrofaciala, malaria and jaw. You can see and arms in women who are treated with exogenous progesterone. Melanin in excess can be viewed located in the dermis and epidermis through a Wood's lamp. Epidermal pigment is revealed during examination with Wood's lamp, while no skin pigment. Clinic is suspected if large amount of dermal melanin is blue-black hyperpigmentation. In people with dark brown skin examination with Wood's lamp does not locate the pigment, and these patients are classified as undetermined.
Diagnosis
Melasma Diagnosis Histological examination. Melanin is increased in the epidermis, dermis, or more frequently in both locations. Melanin is found in epidermal keratinocytes and basal area suprabazala. In most cases the number of melanocytes is not increased, although they are larger, more dendritic and more active. Dermal melanin is found in superficial and deep dermis with macrophages which frequently crowded around the small vessels, dilated. Inflammation is absent.
The differential diagnosis is made with the following diseases: Addison's disease, drug-induced photosensitivity, discoid lupus erythematosus, mastocytosis, poikilodermical of Civatte, actinic plan chargers, linear morphea.