ABSTRACT
BACKGROUND: Eruptive pseudoangiomatosis (EPA) is a rare, benign, spontaneously regressing childhood exanthem. It is characterized by the sudden onset of several bright red angioma-like papules surrounded by pale halos with a distinct histopathology from true angiomas. OBJECTIVE: This study was performed to evaluate the clinical and histopathologic characteristics of EPA occuring in adults. METHODS: Ten adult patients who visited Pusan National University Hospital and Mok Hye-Soo . Jang Ho-Sun Dermatology Clinic from March 2005 to September 2006 were evaluated. We prospectively evaluated the sex, age, onset season, past medical history including immunosuppressive abnormalities, systemic disorders and other diseases including allergies. We also investigated the relations of mosquito biting, patients' occupations and outdoor activities to occurrence of EPA. In addition, simultaneous occurrence in family members, the clinical, histopathologic, laboratory findings, disease courses and responses to treatment were evaluated. Based on medical records, photographs and pathologic slides, we retrospectively diagnosed another 20 EPA patients suspected as insect bite from October 2003 to March 2005. The same questions were inquired as for the 10 patients who prospectively underwent evaluation. RESULTS: In the study, female predominance (76.7%) was observed and the average age of onset was 54.2 years. Interestingly, there was no child patient during the period of study. Multiple, 2~5 mm sized, red angiomatous papules surrounded by pale halos occurred on exposed areas such as the arms (86.7%), legs (50%), and face (46.7%), although it could also occur to a non-exposed area. EPA occuring in adults usually appeared in summer (80%). The mean disease duration was 3.4 weeks. Although EPA spontaneously regressed, it had the potential of recurrence (46.7%). Histopathologic findings showed dilated dermal blood vessels without the evidence of increase in numbers, and perivascular lymphocytes infiltration. Inside the lumen of dermal blood vessels, plump endothelial cells were found. CONCLUSION: EPA occuring in adults usually happened to exposed sites in summer, so it can be misdiagnosed as insect bite. We suggest that dermatologists should be concerned about EPA in adults and conduct further investigation to have a better understanding of the disease.