Pigmentation abnormalities
All over the world, people have varying skin colors due to genetics. Different types of Melanin pigmentation are responsible for skin colour. Abnormalities mean that there is either a absence, a reduction, or an excess amount of melanin affecting parts of the skin or the body’s overall skin color. At birth, one in ten thousand African Americans have melanin deficiency, while one in thirty-six thousand White Americans are affected. Links exist between melanin deficiency or excess and other health conditions, such as Albanism, Addison’s Disease and Parkinson’s Disease.
What is Pigmentation abnormality?
Melanin is photochemical pigmentation present in the skin cells (melanocytes) of the epidermis and functions to produce pigmentation or skin color. There are three types of human melanin: Eumelanin responsible for yellow, brown, grey, and black color of hair and skin; Pheomelanin causing the red to pink color of lips, nipples, and genitals; and Neuromelanin present in pigmented neurons. Environmental and health factors can impact how these types of melanin function or the quantity of melanin produced in the body (melanogenesis). Besides genetics, there are different causes and types of pigmentation abnormalities affecting patches of skin or the entire body.
Types of Pigmentation abnormalities
There are mild types of pigment irregularities ranging from freckles to more severe types of pigment disorders discussed in the following section:
- Freckles (Ephelis)
- Hemochromatosis Disease
- Hemosiderosis Disease
- Jaundice
- Hyperpigmentation and Hypopigmentation
- Albinism
- Melasma or Chloasma
- Vitiligo
Freckles arise due to less photoprotective melanin in the body combined with concentrated amounts of melanin which react to Ultraviolet radiation (UV). Hemochromatosis Disease is hereditary and caused by excess iron absorption causing the skin to appear grey or bronze-like. Hemosiderosis Disease is also excess iron production in the body that may be due to a deficiency of ceruloplasmin, and may result in bleeding of the lungs or respiratory disorders. Jaundice causes yellow skin (sometimes itching due to pruritus) or yellowing whites of the eyes from too much bilirubin left in the blood when iron is removed through death of red blood cells.
Hyperpigmentation is excess melanin, darking skin areas forming patches, such as on the face in Melasma or Chloasma. Hypopigmentation is melanin depletion or not enough amino acid, tyrosine, involved in melanin production that can cause what looks like white scars. The conditions of Vitiligo (smooth white patches) and Albinism (large amounts of white skin with no melanin) are forms of Hypopigmentation. Some of these types have causes that overlap.
Causes of Pigmentation abnormalities
There are a range of causes that result in different types of pigmenation abnormalities, such as:
- Genetic (Freckles, Hemochomatosis, Hemosiderosis, Jaundice, Hypopigmentation – Albinism, and Hyperpigmentation - Melasma)
- Ultraviolet Radiation (Freckles, Hyperpigmentation - Melasma)
- Drugs (Hemochromatosis, Hemosiderosis, Jaundice, Hyperpigmentation)
- Excess Bilirubin (Jaundice)
- Injury, such as infection, inflammation, burns and ulcers (Hypopigmentation)
- Other health conditions (Hemochromatosis; Hemosiderosis - sickle cell anaemia; Jaundice – anaemia, liver malfunction, alcohol liver disease, viral hepatitis; Hyperpigmentation – Addison’s Disease; Vitiligo – Autoimmune disorder)
- Blood transfusions (Hemosiderosis)
- Pregnancy (Jaundice, Hyperpigmentation)
Diagnosing Pigmentation abnormalities
Freckles are visibly present, usually on the face and arms. Blood tests and liver biopsy is used to screen for Hemochromatosis and to monitor blood ferrin (iron) levels. Hemosiderosis is similarly tested, including tests for anaemia, thyroid, adrenalin, and calcium function. Besides the yellowing appearance, various tests can be done to diagnose Jaundice that include stool, urine and blood samples to test biliruben levels. Ultrasound and biopsy may also be used. Hyperpigmentation can be diagnosed at pregnancy or through testing adrenalin gland function. Hypopigmentation is usually clearly visible because the skin patches are white with no melanin color present. Testing melanin levels can be done through biopsy.
Treatments for Pigmentation abnormalities
The section below lists pigmentation abnormalities and treatments as follows:
- Freckles may be treated through creams, sunscreens, and laser treatment.
- Hemochromatosis is treated according to the underlying condition or organ affected, so a patient will be referred to a specialist, such as hematologist, cardiologist, and endocrinologist. Usually patients are told to avoid iron supplements and foods, and Vitamin C. Blood transfusions and phlebotomies may be given.
- Hemosiderosis, depending on the cause or organs affected, may be treated through oxygen supplementation, immunosuppressive therapy, supportive respiratory or ventilatory therapy, and blood transfusions.
- In the case of Jaundice, the cause needs to be identified for treatment, however vaccines are available to prevent Hepatitis A and B, and people can seek treatment for alcoholism before liver damage is severe.
- Hypopigmentation has no cure, but Vitiligo can be treated through corticosteroid creams and photo/ light therapy. Treatments for Albinism are mainly use of sunscreen to protect the skin from cancer. Cosmetics are sometimes used to cover and blend into parts of the skin for improved appearance.