Acquired hyperpigmentations

Abstract

Cutaneous hyperpigmentations are frequent complaints, motivating around 8.5% of all dermatological consultations in our country. They can be congenital, with different patterns of inheritance, or acquired in consequence of skin problems, systemic diseases or secondary to environmental factors. The vast majority of them are linked to alterations on the pigment melanin, induced by different mechanisms. This review will focus on the major acquired hyperpigmentations associated with increased melanin, reviewing their mechanisms of action and possible preventive measures. Particularly prominent aspects of diagnosis and therapy will be emphasized, with focus on melasma, post-inflammatory hyperpigmentation, periorbital pigmentation, dermatosis papulosa nigra, phytophotodermatoses, flagellate dermatosis, erythema dyschromicum perstans, cervical poikiloderma (Poikiloderma of Civatte), acanthosis nigricans, cutaneous amyloidosis and reticulated confluent dermatitis.

FIGURE 1

Acquired hyperpigmentations. Moderate melasma, brown spots with irregular edges affecting the right hemiface, following a mandibular pattern in a patient with phototype V

FIGURE 2

Acquired hyperpigmentations. Severe melasma. Patient with skin phototype IV, presenting a somewhat homogeneous lesions, but with intense pigmentation, predominantly in the middle facial region

FIGURE 3

Acquired hyperpigmentations. Postinflammatory hyperpigmentation – bluish brown macules distributed around the trunk, secondary to extensive pityriasis rosea

FIGURE 4

Acquired hyperpigmentations. Periorbital hyperpigmentations – Depression and shaded aspect, with visualization of the superficial vascular network in the infraorbital region of a 38 years-old woman

FIGURE 5

Acquired hyperpigmentations. Phytophotodermatoses – hyperchromic brown spots, with a leaked aspect, located on the dorsal area of the hand and fingers, secondary to accidental contact with lemon juice followed by sun exposure

FIGURE 6

Acquired hyperpigmentations. Flagellate Dermatitis– Linear urticariform lesions, some with a slight superficial blistering, located on the lateral side of the chest, which appeared 15 days after the initiation of treatment with bleomycin

FIGURE 7

Acquired hyperpigmentations. Erythema Dyschromicum Perstans – Grayish macules of varying sizes, located on the anterior region of the thorax, abdomen and upper thighs of a 27 years-old woman

FIGURE 8

Acquired hyperpigmentations. Poikiloderma of Civatte. Note the grid-like hyperpigmentation, affecting the lateral areas and base of the neck in a 51 years-old phototype 3 woman. Observe photodamage lesions and a lighter area correspondings to the region shaded by the chin

FIGURE 9

Acquired hyperpigmentations. Acanthosis nigricans – Linear and coalescent papular hyperpigmentation, with velvety aspect, located in the axillary region of an obese adolescent

FIGURE 10

Acquired hyperpigmentations. Macular amyloidosis– a brownish itchy area, located in the dorsal region, corresponding to the range area of a dextral patient’s hand

FIGURE 11

Acquired hyperpigmentations. Amyloid lichen – plaque formed by the confluence of small grayishbrown papules located in the pretibial region