Histopathologic examination of hyperpigmented lesions has shown diffuse hypermelanosis
of the entire epidermis with no melanin incontinence and a sparse perivascular lymphocytic infiltrate in the dermis in a previous study.4 Similar findings of increased basal layer pigmentation and lymphocytic infiltrate were noted in this study, but in addition melanophages were also seen in the dermis.
Melasma is a word originating from Greek melas, meaning "black." It is a very common hypermelanosis
, characterized by well-demarcated gray-brown patches that occur frequently on sun-exposed areas of the face and rarely on the neck and forearms.
Incontinentia pigmenti, linear and whorled nevoid hypermelanosis
, and progressive cribriform and zosteriform hyperpigmentation follow a linear pattern.
Studies on tyrosinase inhibitors, such as hydroquinone, azelaic acid, kojic acid, and arbutin, can effectively expand the scope of research on hypermelanosis
Melasma (also known as chloasma or mask of pregnancy) is an acquired, chronic, symmetrical hypermelanosis
, characterized by brown patches of variable darkness on sun-exposed areas of the body.
* Associated with systemic diseases (e.g., Addison's disease, Peutz-Jeghers syndrome) Palmoplantar Due to localized hypermelanosis
hyperpigmentation * Polymorphous brown macules with sharp or indistinct borders * Creases on the palms often present with hyperpigmentation; may contain hyperkeratotic papules or pits.
There may also be hyperpigmentation of the buccal mucosa that may be reactive postinflammatory hypermelanosis
. (10) In our case, the patient had no white keratotic patch, vesicles, ulcerations, or any other associated oromucosal abnormality; he had healthy periodontium and teeth.
Melasma, also known as Chloasma or mask of pregnancy is an acquired, chronic, and symmetrical hypermelanosis
, characterized by brown patches of variable darkness on sun exposed areas of body .
Effect of Artemia nauplii enriched with vitamin-A palmitate on hypermelanosis
on the blind side in juvenile Japanese flounder Paralichthys olivaceus.
Hypomelanosis and Hypermelanosis
. Irwin MF, Arthur ZE, Klaus W, K Frank A, Lowell AG, Stephen IK.
Well-delineated areas of hypermelanosis
affect the face and neck.