Skin pigmentation lecture

1. pegmentation
SKIN

2. Hyperpigmintation and
Melasma
Dr. Bassam Aldharasi

3. Hyperpigmentation (Hypermelanosis)
Hyperpigmentation is skin
darkening brought about by an
excess of melanin pigment in
the skin
Melanocytes are specialized
skin cells, which when exposed
to sunlight result in the
production of more melanin
pigment. This causes the outer
layer of the skin to tan and
darken.

4. Causes of Hyperpigmentation
A. Congenital
Circumscribed
• Nevus of Ota
• Nevus of Ito
• Mongolian spot
• Dermal melanocytic hamartoma
• Lentiginosis (generalized,
zosteriform, eruptive, centrofacial)
• Café-au-lait macules
Diffuse
• Incontinentia pigmentii
• Linear and whorled nevoid hypermelanosis
• Dyskeratosis congenita
• X-linked reticular pigmentary disorder
• Naegeli–Franceshetti–Jadassohn syndrome
• Dermatopathia pigmentosa reticularis
• Dyschromatosis hereditaria universalis
• Reticulate acropigmentation of Dohi
• Reticulate acropigmentation of Kitamura
• Dowling–Degos disease
• Familial progressive hypermelanosis

5. Causes of Hyperpigmentation
B. Acquired
Circumscribed
• Freckles
• Fixed drug rash
• Post-inflammatory
hyperpigmentation
• Becker’s nevus
• Nevus of Hori
• Riehl’s melanosis
• Erythema dyschromicum perstans
• Flagellate pigmentation
Diffuse
• Endocrine: Addison’s disease, Cushing’s
syndrome, Melasma, pregnancy, diabetes,
acanthosis nigricans
• Nutritional: Kwashiorkor, pellagra,
vitamin B12 deficiency
• Metabolic: prophyria, cutanea tarda,
hemochromatosis
• Physical: radiation, trauma
• Drug induced: clofazimine, amiodarone,
zidovudine, antimalarials, minocycline

6. Causes of Hyperpigmentation
C. Others
Non-melanin causes of brown–black discoloration
Haemosiderin – from broken haem pigment in extravasated blood
Homogentisic acid – deposited in cartilage, in particular, in the inherited
metabolic defect known as alkaptonuria
Drugs and heavy metal toxicity – dark pigmentation of the skin and mucosae
seen in silver, gold, mercury, and arsenic poisoning; amiodarone and
phenothiazines cause slate-grey, dusky skin pigmentation in exposed sites;
minocycline may cause patchy pigmentation in exposed or other sites

7. Genralized hyperpigmentation
Types of Hyperpigmentation
1.Addison’s disease
due to destruction of the adrenal cortex Pigmentation
is marked in the flexures, sites of trauma, scars, and
sun-exposed areas, but the mucosae and nails are
also hyperpigmented.
.2.Acanthosis nigricans
which is much more marked in the flexures and is
accompanied by exaggerated skin markings and skin
tags.
3.haemochromatosis (bronzed diabetes)
in which iron is deposited in the viscera, including
the pancreas (giving rise to diabetes) and the liver
(causing cirrhosis The pigmentation is more
pronounced over sun-exposed areas, genitalia, and
scars.

8. Localized hyperpigmentation
Types of Hyperpigmentation
1. Mongolian spots, the naevus of Ota, and
the naevus of Ito
are large, flat, grey–brown patches and can be
confused with bruising and other conditions The
bluish color is attributed to the Tyndall effect.
2. chloasma or melasma:
3.Riehl’s melanosis (pigmented cosmetic
dermatitis)
is frequently seen over the forehead. Post-
inflammatory hyperpigmentation may be due to
melanocytic hyperplasia occurring as part of
epidermal thickening in chronic eczema, particularly
atopic eczema.

9. Melasma

10. Introduction
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11. Melasma
• Melasma is an acquired
hyperpigemrntaion disorder
which is the dark
brown skin pigmentation that is
observed in regions of sun
exposure.
• Melasma can occur anywhere in
the body but is usually noticed
on the face
• is more common in female but it
dose occur in male.
• It’s also called chloasma, or the
“mask of pregnancy

12. Clinical picture
02

13. Symptoms of melasma
Melasma causes patches of discoloration. The patches
are darker than usual skin color. It typically occurs on the
face and is symmetrical, on both sides of the face. Other
areas of body that are often exposed to sun can also
develop melasma.
1. cheeks
2. forehead
3. bridge of the nose
4. chin
It can also occur on the neck and forearms.
The skin discoloration doesn’t do any physical harm, but
you may feel self-conscious about the way it looks.

14. Aetiology
03

15. Sunlight: sunlight triggers the body to produce more
melanin.
Pregnancy: An increase in the hormones
estrogen and progesterone, which occurs during
pregnancy, is thought to trigger melasma.
Some medications: The following medications may
trigger melasma in some people:
Anti-seizure medications
contraceptive pills
Medications make skin more sensitive to sunlight
(includes retinoids, some antibiotics,)
Stress: An increase in cortisol may elasmtrigger ma.
Thyroid disease:
Causes and risk factors of melasma

16. Diagnosis
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17. by looking closely at the face and neck using:
Wood’s lamp or dermatoscope. Placed on (or near) the skin
skin biopsy, which involves removing a small bit of skin.
Diagnosis of melasma

18. Treatment
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19. The goals of treatment are to
• Decrease how much pigment your
body makes.
• Even out your skin tone, restoring
it to your natural color.
Treatment of melasma
The goals of treatment are to

20. Treatment of melasma
Skin protiction
Sunscreen with zinc
oxide, iron oxide
hydroqunion
Commmn treatment
Triple compination
creamed
others
As Vitamin c
Tertinoin and a
mild compination of
corticosteroids
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