Autoimmune diseases

A Young Woman with Lightening of Skin

Ronald Rubin, MD—Series Editor

A 29-year-old woman presents for evaluation of changes in her skin. Several months ago, in the spring, she had noticed lightening of her skin in both elbow areas as well as her forehead area where the band of her frequently worn baseball style hat sat on her forehead. Then, more recently, after a vacation at the shore, yet more skin lightening appeared elsewhere on her face and torso where her bathing suit fit. These areas did not itch. There was no history of drug exposure or changes in her detergent, soap, or shampoo. She had applied a standard commercial sunscreen that she had used this in the past.

History

Her health otherwise is excellent with no chronic diagnoses. She has been on oral contraceptives for about 5 years, but otherwise takes no other medicines or dietary supplements.

Physical Examination

Physical examination is entirely within normal limits, except for her skin. Examination of the affected areas shows macules of homogeneous depigmentation with well-defined borders. Several of the more recent, post-vacation lesions demonstrated slightly hyperpigmented “rims.”

Which of the following is the most likely diagnosis?

A. She can expect her symptoms to stabilize and resolve if she avoids future sun exposure.

B. She is a good candidate for therapy with surgical techniques, such as autologous grafting or removal.

C. She is at increased risk for associated autoimmune disorders.

D. Treatment with local and/or systemic immunosuppressive agents is the initial measure of choice here.

(Answer and discussion on next page)

Correct Answer: C

The presented patient is manifesting vitiligo, the most common depigmenting disorder. Demographics of vitiligo include early age of onset (>50% prior to age 30); prevalence of 0.5% with an equal distribution by sex and race.1 She is manifesting the more common variety of generalized or nonsegmental vitiligo—attributed to 85% of cases.1 This variety results in a nondermatomal, usually bilateral, symmetric, and diffuse depigmentated patches. 

Nonsegmental vitiligo is progressive with periodic flare-ups and thus Answer A is not correct. As was the situation in our case, lesions are most common in skin sites sensitive to pressure or trauma (ie, where a hat fits around the forehead or an area of tight fitting, such as belt lines or bathing suits).

Pathogenesis

The pathogenesis of the condition involves the loss of epidermal melanocytes of an as yet poorly understood initial cause.1,2 Candidate causes or associations include neurogenic disorders (the most localized segmental form often involves dermatomes) and genetic/autoimmune factors. In population studies, genetic epitope clusters have been found and a clear personal and familial autoimmune diathesis has been clearly demonstrated.1 Thus Answer C is correct. Associated autoimmune phenomena include thyroid disease, pernicious anemia, and rheumatoid arthritis.

Diagnosis

Diagnosis can usually be made clinically with the finding of macules of homogeneous depigmentation and well-defined borders. Hyperpigmented rims in areas of sun exposure are also typical. A detailed examination by the dermatologist with a Woods ultraviolet lamp further confirms the depigmentation, well-defined borders, and related typical findings mentioned earlier. Skin biopsy is rarely, if ever, required to confirm the diagnosis.

Treatment

A variety of therapies are used in vitiligo. Their specifics are in the very specialized realm of dermatology, but an overview can be discussed here. An efficacious initial therapy is often narrowband ultraviolet (UV) B irradiation, which yields an efficacy (meaning repigmentation of 50% to 75%) in about two-thirds of patients.3 

Other therapies are more suited to more localized cases and include topical steroids and/or calcineurin inhibitors. In cases where extremely focal, limited extent, and stabilized vitiligo (usually the segmental form), surgical removal and grafting has been used. Our patient manifests a more generalized syndrome and has not demonstrated any stability as yet so surgical techniques. Answer B is not appropriate here. 

Systemic autoimmune therapies, such as corticosteroids and biologic modifiers, have been used in a limited basis and have a sporadic literature but require far more systematic study and trial evaluation before attaining standard of care status in any vitiligo situation and thus, Answer D is not correct.

Outcome of the Case

Subsequent skin examination including Woods lamp evaluation confirmed the diagnosis of vitiligo in the nonsegmental form. The initial plan of therapy is twice weekly narrowband UV therapy with evaluation of response at 3 months and total therapy for 9 months if responding. There was significant repigmentation at 3 months such that treatment is ongoing.

Ronald Rubin, MD, is a professor of medicine at Temple University School of Medicine and chief of clinical hematology in the department of medicine at Temple University Hospital, both in Philadelphia, PA.

References:

1. Taïeb A, Picardo M. Vitiligo. N Eng J Med. 2009;360:160-168.

2. Jin Y, Mailloux CM, Gowan K, et al. NALPI in vitiligo-associated multiple autoimmune disease. N Engl J Med. 2007;
356:1216-1225.

3.Bossuyt PM. Nonsurgical repigmentation therapies in vitiligo: meta-analysis of the literature. Arch Dermatol. 1998;134:
1532-1540.