Epidermolysis bullosa simplex with mottled pigmentation
Overview
Epidermolysis bullosa simplex with mottled pigmentation: A variant of a skin blistering disease which also involved a skin pigmentation anomaly.
Symptoms
The list of signs and symptoms mentioned in various sources for Epidermolysis bullosa simplex with mottled pigmentation includes the 10 symptoms listed below: * Mottled skin pigmentation * Fragile skin * Skin blisters * Thickened skin on palms * Thickened skin on soles * Easily bruised legs * Curved nails * Mottled skin pigmentation on arms and legs * Thick, hard patches of skin on soles * Blisters on extremities
Causes
* Acanthosis nigricans –Velvety, hyperpigmented thickening of skin folds (e.g., axillae, groin, neck, and inframammary regions) –Associated with insulin resistance (e.g., DM, Cushing's diseases, hypothyroidism, obesity, polycystic ovarian syndrome, and exogenous corticosteroids) * Tinea versicolor –Mottled macular hyperpigmentation (and/or hypopigmentation) in rings and circles with little or no scale –Often on the upper trunk and shoulders –Caused by Pityrosporum orbiculare and P. ovale, which look like “spaghetti and meatballs” on KOH preparation –May be pruritic during acute phase, particularly in warm environments that encourage growth of the fungus * Postinflammatory hyperpigmentation –Patchy, transient hyperpigmentation after resolution of inflammatory rashes * Melasma (chloasma, “mask of pregnancy”) –Gradual blotchy macular hyperpigmentation, especially of the malar surfaces, chin, and forehead –Occurs with oral contraceptives, pregnancy, or idiopathic –May fade postpartum or after discontinuing oral contraceptives, and recur if either occurs again * Grey or blue hyperpigmentation –Medications: Amiodarone, minocycline, imipramine, chemotherapeutic drugs (e.g., bleomycin, doxorubicin), antimalarials, AZT –Heavy metal poisoning * Incontinentia pigmenti –Genetic disorder with associated systemic abnormalities; the final stage of skin disease can present as linear and whorled streaks or hyperpigmentation * Hemochromatosis –Diffuse hyperpigmentation * Diabetic dermopathy –Hyperpigmented, round, atrophic lesions on shins of diabetics
Diagnosis
The serum iron and iron-binding capacity should be measured to rule out hemochromatosis. A thyroid profile will exclude hyperthyroidism. A serum cortisol and ACTH stimulation test will identify Addison's disease. A urine for porphyrins and porphobilinogen will diagnose porphyria. A urine N -methyl niacinamide will help diagnose pellagra. If there is still doubt after these studies are done, a skin or liver biopsy may be done to rule out hemochromatosis, and a CT scan of the abdomen will help identify Addison's disease.
Treatment
* Acanthosis nigricans improves with adequate treatment of the underlying endocrine disorder; treatments may include weight loss, dietary/medication control of insulin resistance, and topical exfoliants (e.g., lactic acid, tretinoin, urea-based medications) * Tinea versicolor: Treatment includes topical (e.g., ketoconazole) or oral antifungals (e.g., fluconazole); normalization of pigmentation may take many months; long-term maintenance therapy is necessary to prevent recurrence * Melasma often improves spontaneously after pregnancy or discontinuation of oral contraceptives; sun avoidance and topical retinoids and hydroquinones facilitate normalization of pigment; chemical peels or laser procedures restore normal pigmentation * Avoid offending medications; adjuvant laser therapy may be necessary to remove or destroy residual drug particles, hemosiderin, or excess melanin in skin