Linear lichen planopilaris of the trunk: first report of a case.
BACKGROUND
Lichen planopilaris (LPP) is believed to be a follicular variant of lichen planus that affects pilosebaceous units, mainly of the scalp. An extremely rare variant of LPP is a linear form, which follows the lines of Blaschko. Of the five previously documented cases of linear LPP, all were limited to the face.


OBJECTIVE
We report the case of a 34-year-old male who presented with a nonpruritic eruption on the trunk consisting of erythematous, keratotic, folliculocentric papules following Blaschko's lines.


RESULTS
Biopsy revealed lichenoid and interface dermatitis involving the basilar epidermis and hair follicles, as well as apoptotic keratinocytes, consistent with LPP.


CONCLUSIONS
This represents the first documented case of LPP, following the Blaschko's lines, in a nonfacial distribution.
Baker
Kristi
K
Department of Pathology, Division of Dermatology, SMBD-Jewish General Hospital, McGill University, Montreal, QC.
Pehr
Kevin
K
D000287:Administration, Topical; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D003937:Diagnosis, Differential; D006801:Humans; D006854:Hydrocortisone / Q000627:therapeutic use; D008010:Lichen Planus / Q000188:drug therapy / Q000473:pathology*; D008297:Male; D013909:Thorax / Q000473:pathology*
D000893:Anti-Inflammatory Agents; D006854:Hydrocortisone