Leukoderma: Description, Causes and Risk Factors:
Absence of pigment (melanin), partial or total, in the skin.
Alternative Name: Hypomelanosis, leukopathia.
Melanocytes are the pigment-producing cells of the skin. They reside mainly in the basal layer of the epidermis and the matrix of the hair follicle. Melanocytes are highly dendritic cells; their origin is the neural crest, from where they migrate during embryogenesis. Within the cytoplasm of the melanocytes, the melanin pigment is deposited in specific organelles named melanosomes. As the melanosomes mature and acquire melanin, they move to a perinuclear position into the dendrites. Each melanocyte interconnects with 36 keratinocytes. These surrounding keratinocytes phagocytize the tips of the melanosome-containing dendrites and transfer the pigment. This transference is essential for normal skin pigmentation. The differences between color in skin resides not in the number or density of melanocytes but in the activity of the individual melanocytes. In darker skin, a greater number of mature melanosomes with an increased level of melanin production is found.
Leukoderma is a condition in which the skin layers experience loss of skin-pigment. Leukoderma causes white patches on the skin surface. It is more common in women than in men and is mostly seen on the hands, neck, back and wrist. They can be either congenital/hereditary or acquired. The pattern of involvement can be circumscribed, diffuse, linear, or reticulated.
Leukoderma is not contagious i.e. it cannot spread by touching someone or even by handling personal belongings or food.
The leukoderma sufferers are observed all over the world, including the white skin communities. However, epidemiologically most cases are recorded in India and Mexico. Males and females are affected equally, inclusive of children age group. It may begin at any age.
Possible causative reason may include:
Disappearance or destruction of melanin from the skin secondary to any cause.
- In coordination in melanosomes degradation in the epidermal keratinocytes.
- Disturbances in the transfer and melanisation of melanosomes.
- Lack of formation of melanosomes matrix in the melanocytes.
- Disturbances in the synthesis and transport to tyrosinase.
- Lack of proper mitosis of melanocytes.
- Lack of migration of melanoblasts to the skin and disturbances in the transformation of melanoblasts into melanocytes.
The main causes of leukoderma are said to be excessive mental worry, chronic or acute gastric disorders, impaired hepatic function such as jaundice, worms or other parasites in the alimentary canal, typhoid, a defective perspiratory mechanism, and burn injuries. Heredity is also a causative factor and about 30 per cent of patients have a family history of the disorder.
Risk factors may include:
Malignancy of skin.
- Diabetes mellitus.
- Malignant melanoma.
- Pernicious anaemia.
- Alopecia areata.
- Addison's disease.
- Thyroiditis and thyroid carcinoma.
- Hyperthyroidism as also hypothyroidism.
- Toxic and simple goiter.
The whiteness starts as a small discolored white or pale brown spot, which spreads and becomes whiter after a few days, finally turning milky white in color.
- Premature graying of hair.
- Alopecia or loss of hair.
- General weakness.
- Sensitivity towards cold.
- Hair on the affected area also become white.
Differential diagnosis may include:Piebaldism, hypomelanosis of Ito, tuberous sclerosis, lupus erythematosus, scleroderma, sarcoidosis, Lichen sclerosus et atrophicus, halo nevi, pityriasis alba, mycosis fungoides, tinea versicolor, leprosy, idiopathic guttate hypomelanosis, postinflammatory hypopigmentation, segmental vitiligo, nevus anemicus, nevus depigmentosus, Steroid-injection-related hypomelanosis.
Diagnosing the patient with leukoderma is very easy and simple. Everyone can easily identify the disease as leukoderma with its characteristic whiteness of the skin.
When a health professional assumes that a person suffer from leukoderma, he/she instigates inquiring the person concerning his or her medical history. Medical history of a person includes a history of vitiligo in family, sunburn, or other skin sufferings of vitiligo before depigmentation started. However the doctor will observe the patient having other medical problems. The doctor may recommend a blood test or an eye examination to find out the antinuclear antibodies presence. All this help to make a precise conclusion whether the patient has another autoimmune diseaseor not.
Since leukoderma is restricted to the epidermis, there would not be any change in blood or urine. Biopsy can reveal the absence of pigments. Fungal infections can resemble vitiligo patches. So, in doubtful cases, it has to be ruled out with biopsy and culture. Also, sensation over the leukoderma is normal, compared to other discoloration diseases.
There is no scheduled conservative treatment for leukoderma. No single therapy for leukoderma produces good results in all patients. Treatment course and medicines always vary and are unpredictable. Usually, treatment is a long process which may take months or years.
As doctors prescribe, people go for internal medicines, external applications, radiation therapy, photosensitivity therapy, depigmentation therapy with bleachers and surgery. All have their own side-effects and limitations. Patients should be aware of the risks of drugs or procedures before undergoing treatment.
Surgical Options May Include: Transplantation of the epidermis, autologous suction-blister grafts, autologous punch grafts, and autologous melanocyte transplant are some of the possible surgical procedures that should be practiced only on teenagers or adults.
Method to be used depends on the type and site of lesion. Hence, selection of the appropriate surgical technique is important for good cosmetic results.
Miniature punch grafting.
NOTE: The above information is educational purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.
- Ultra thin skin grafting.
- Suction blister grafting.
- Therapeutic spot or regional dermabrasion.
- Melanocyte culture and transplantation.