Unusual presentation: concomitant segmental vitiligo, segmental morphea, and lichen striatus.

Background: Segmental vitiligo, segmental morphea, and lichen striatus are distinct dermatological conditions that may share pathogenic mechanisms involving genetic mosaicism and immune dysregulation. Their simultaneous occurrence is extremely rare and may offer insights into their shared etiology.

Case presentation: A 24-year-old female presented with a 6-year history of progressive indurated and discolored skin lesions. Dermatological examination revealed dermatomal depigmented macules consistent with segmental vitiligo on the right trunk, a violaceous Blaschkoid macule compatible with lichen striatus on the right lateral trunk, and multiple sclerotic plaques on the left side, consistent with segmental morphea. Histopathological examination confirmed the diagnosis of all three entities: loss of melanocytes in vitiligo, dermal sclerosis in morphea, and epidermal spongiosis with lymphocytic infiltrates and melanophages in lichen striatus.

Conclusion: To our knowledge, this is the first reported case presenting the concurrent manifestation of segmental vitiligo, segmental morphea, and lichen striatus in the same patient. The segmental and Blaschkoid distribution patterns support a common pathogenic basis likely rooted in genetic mosaicism triggered by an autoimmune mechanism. Recognition of this rare co-occurrence may help elucidate the shared immunopathological mechanisms underlying these conditions.