Abstract: Clinical and pathological data of 9 cases with acquired reactive perforating collagenosis from Jan.2015 to Dec.2017 were retrospectively analyzed. The ratio of male to female was 1:1.25. The average age at onset was 53.89 years old. The average duration was 9.67 months. The biopsy shows denatured collagen fibers within the epidermis. There were 8 cases (88.9%) with diabetes, 2 (25%) with hypertension. All 9 patients were misdiagnosed as other diseases, including prurigo nodular , eczema , cutaneous vasculitis , pyoderma gangrenosum skin?ulcers , mycotic infection , neurodermitis prurigo bullous pemphigoid , epidermolysis bullosa, ?lichen planus(1 time).

Key words: acquired reactive perforating collagenosis, clinic, pathology