A 27-Year-Old Woman With White Spots on Her Face

Discussion

The diagnosis of vitiligo was made clinically on the basis of the patient’s characteristic history and the physical examination findings. The painless, sharply demarcated, demelanotic macules and patches appeared in a linear distribution above her right eyebrow, in keeping with the diagnosis of segmental vitiligo, which affects one side of the body. These hypopigmented macules and patches were also nonscaly, as is classically described. The patient’s history and physical examination ruled out a diagnosis of idiopathic guttate hypomelanosis, as this condition primarily affects the middle-aged and elderly population.

Patients typically present with hypopigmented macules of 2-5 mm on sun-exposed areas of the upper and lower extremities, such as the extensor surfaces of the forearms and legs. These lesions also have a slight xerotic scaling and remain the same size, though their numbers increase. The physical examination also ruled out a diagnosis of tinea versicolor, which presents with small circular macules, usually on the upper back and chest wall, which have a white scale when scratched and golden fluorescence when examined under a Wood's lamp. The normal nervous system examination findings ruled out a diagnosis of tuberculoid leprosy, as these patients have asymmetric macules or patches of hypomelanosis that are insensitive to pain, heat, and touch. Associated anhidrosis and alopecia is also present. The elevated total T3 and T4 findings supported the diagnosis of vitiligo because many patients with vitiligo have an associated autoimmune disease, such as Graves disease or Hashimoto thyroiditis.

Vitiligo is a pigmentation disorder of unknown etiology in which melanocytes in the affected skin and mucous membranes are destroyed. This destruction is thought to be caused by an autoimmune process because patients with vitiligo have a high incidence of antibodies to melanocytes.^[1] Vitiligo affects approximately 1% of the world’s population.^[2] Furthermore, approximately 30% of vitiligo patients have a positive family history of the disorder.

In an analysis of genome-wide data that tested 33 candidate genes for generalized vitiligo, investigators found an association with TSLP, XBP1, and FOXP3.^[3] When the investigators evaluated CTLA4, the association with generalized vitiligo appeared to have a secondary epidemiologic association with other concomitant autoimmune diseases. Furthermore, linkage disequilibrium with major primary signals in the major histocompatibility complex (MHC) I and II regions at 6p21.33 may be the source of an association between TAP1-PSMB8 and generalized vitiligo.^[3]

Depigmentation can begin in childhood, and more than 75% of patients present before age 30 years. The disease is characterized by sharply demarcated, depigmented, nonscaly round or oval macules and patches on the skin and mucous membranes that range from a few millimeters to several centimeters in size. The condition is usually nonerythematous. The initial lesions occur most commonly on sun-exposed areas, such as the face, forearms, and dorsal surfaces of the hands and feet. Vitiligo has a periorificial predilection, with areas around the mouth, nose, eyes, nipples, umbilicus and anus commonly being affected. The axillae and genitalia are also commonly involved. Vitiligo may also develop at sites of trauma, such as cuts or burns (Koebner phenomenon). Sweating is increased in the depigmented areas while there may also be leukotrichia or depigmentation of the scalp hair, eyebrows, eyelashes, beard, and pubic hair. Patients with localized segmental vitiligo and poliosis usually do not have associated autoimmune diseases.

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Cite this: Miriam Kinai. A 27-Year-Old Woman With White Spots on Her Face - Medscape - Mar 17, 2011.