Acquired pigmentary disorder. White macules and patches appear secondary to selective loss of melanocytes in the skin / mucous membranes.
50% of the time, age of onset is under 20 years old.
Can occur as a Koebner Phenomenon (occurs at injured sites)
When over 80% of the body surrface is covered
Least common type of vitiligo
Vitiligo - Treatment
Topically sunscreens, corticosteroids, vitamin D analogues, and calcineurin inhibitors can work.
Ultraviolet therapy can work as well
Nevus surrounded by a halo of depigmentation
+/- white hairs in depigmented area
Common in children, more worrisome in adults
Occurs in 70-90% of patients with Tuberous Sclerosis.
Reddish-brown smooth papules with a centro-facial distribution. Hundreds can occur and expect increased numbers with age.
Incidence of 1:6000
1/3 are autosomal dominant, while 2/3 are sporadic
Patients have Hamartomatous tumors in multiple organs such as the brain, heart, kidney, skin, lungs, eyes. These are benign, but may cause problems.
Classic triad of seizures, mental retardation and skin lesions.
Ungal Fibromas (Koenen Tumors)
Affects 88% of tuberous sclerosis cases.
Toes are affected more than fingers. Periungal or subungal growths on the toes.
Incidence of 1:3000
Autosomal dominant 50% or sporadic 50%
NF-1 gene that is a tumor suppressor is affected. This encodes Neurofibromin which inhibits the RAS proteins involved in regulation of cell proliferation.
All patients will have "Cafe au Lait spots"
Patients have neurofibromas too (benign tumor of nerve sheath)
Patients will have Lisch Nodules in eyes too
The elephant man had neurofibromatosis.
Slight raised well-circumscribed melanocytic hamartomas of the iris.
This is pathognomonic for neurofibromatosis
Neurofibromatosis - Prognosis
Lifelong and progressive
Phenotype is highly variable
Average life expectancy reduced by 15 years
Increased risk of malignancy for the peripheral nerve shealth tumors, pheochromocytoma, as well as CML, and ALL
Neurobehavioural problems are common
Is a mast cell tumor.
Mast cell granules contain histamine.
Usually occurs in young children.
Usually spontaneously resolves over a few years.