Purpura annularis telangiectodes of Majocchi: A case report

BACKGROUND: Purpura annularis telangiectodes of Majocchi (PATM), also known as Majocchi, is a rare subclass of pigmented purpuric dermatoses. The etiology of PATM is unknown, but it seems more common in children and young women. The skin lesions are mostly symmetrical ring-shaped reddish-brown macules on the lower limbs. CASE SUMMARY: A 9-year-old girl, who has received treated in our department, presented with reddish-brown ring-shaped rash on both lower limbs that had been present for 6 mo. These lesions, red brownish annular or petaloid patches, were mostly found on ankles and lower limber, which do not fade when adding pressure and no feel of infiltration and no atrophy when touching those lesions. Pathological examination showed deposition of hemosiderin in papillary dermis. However, dermoscopy showed the pigmentation in the center as well as the lavender patches on the edge of lesion. The child was thus diagnosed with PATM. After diagnosis, we suggested the patient avoid strenuous exercise. she was given vitamin C tablets for oral and mometasone furoate cream for external use. Follow-up examinations and treatment continue to support the clinical diagnosis to date. CONCLUSION: This is the first report of investigating PATM using dermoscopy, which can differentiate PATM from other diseases due to its unique microscopic feature under dermoscopy. Although PATM is harmless, it still requires long-term follow-up. Moreover, dermoscopy technique can be applied for observation of multi-site lesions and correlated with histopathology. Thus, we believe this approach could be generalized for future diagnosis of PATM.