Atypical Linear Atrophoderma of Moulin Complicated with Elevated Immunoglobulin M: A Case Report

Linear atrophoderma of Moulin (LAM) is a rare acquired skin disease. Clinically, LAM is characterized by hyperpigmented and atrophic unilateral band-like or linear dermatoses of variable size following the Blaschko lines. The lesions do not present induration or sclerosis. Its course is asymptomatic without systemic involvement or progression. The etiology of LAM is still unclear. Based on the characteristics of its skin lesions distributed along the Blaschko lines, some scholars speculate that its pathogenesis may be related to chromosome mosaicism. We hereby present a case report of LAM in a 29-year-old Chinese female who had persistent brown patches distributed along the Blaschko lines on the left lower back, buttocks, and lower limbs with positive antinuclear antibody (ANA, 1:320, nucleolar type) and elevated immunoglobulin M (3.47 g/L). Including this case, a total of 6 LAM cases have been reported to have abnormal serum immunological markers.