Vitiligo: Segmental Type with Rapid Onset

Diagnosis: Vitiligo (Segmental)

A 16-year-old female presenting with sharply demarcated depigmented patches in a unilateral dermatomal distribution on the left face and neck.

Clinical Presentation

Well-defined, chalk-white depigmented macules and patches in a band-like distribution involving the left forehead, periorbital area, and extending to the left side of the neck. Does not cross the midline. Under Wood lamp, lesions are bright white. Poliosis in affected eyebrow.

Clinical History

Onset 3 months ago with rapid progression over 6 weeks before stabilizing. No preceding trauma or sunburn. No personal or family history of autoimmune disease. Thyroid function tests normal.

Treatment

Topical tacrolimus 0.1% ointment twice daily for facial lesions. Narrowband UVB phototherapy (3x/week) initiated. Topical mometasone furoate 0.1% applied on alternate days. Melanocyte transplantation discussed once stable.

Differential Diagnosis

• Pityriasis alba • Pityriasis versicolor • Post-inflammatory hypopigmentation • Chemical leukoderma • Tinea versicolor • Morphea • Leprosy • Mycosis fungoides (hypopigmented)

Key Learnings

• Autoimmune destruction of melanocytes — T-cell mediated • Wood lamp accentuates depigmented areas (bright white fluorescence) — essential for diagnosis in fair skin • Segmental vitiligo: dermatomal distribution, earlier onset, less associated with autoimmune disease, more stable • Non-segmental vitiligo: progressive, bilateral, associated with autoimmune thyroid disease, type 1 DM, pernicious anemia • Koebner phenomenon present • Screen for associated autoimmune diseases: TSH, CBC, vitamin B12 • Ruxolitinib cream (JAK inhibitor) FDA-approved for non-segmental vitiligo • Repigmentation often starts perifollicularly (from follicular melanocyte reservoir)

Tags: vitiligo, depigmentation, phototherapy, autoimmune, segmental