Panniculitis, an Uncommon Skin Manifestation in Adult Dermatomyositis

Abstract

Objective: The skin manifestations of dermatomyositis (DM) are complex and diverse, with some rashes having diagnostic significance, while others have a certain suggestive effect on the patient’s condition, visceral damage, and prognosis. This case-cohort study was performed to investigate the skin manifestations of 205 adult inpatients with DM. We then analyzed the association between the clinical characteristics and panniculitis in adult patients with DM. Methods: This study was conducted at the First Medical Center of PLA General Hospital, Beijing, China from March 1, 2016 to December 30, 2020 with follow-up until December 31, 2021. This case-cohort study involved 205 eligible participants with DM who met the criteria for idiopathic inflammatory myopathy. Clinical data, cutaneous manifestations, and lesion locations were screened and analyzed. Serum samples were collected, and immunoblotting was used to detect 16 types of myositis-specific antibodies and myositis-associated antibodies. Results: The results showed that 16 (7.8%) of the 205 adult patients with DM had panniculitis. The panniculitis was mainly distributed in the subcutaneous fat of the abdomen, buttocks, and thighs. This condition was often accompanied by skin ulcers, atrophic scars, and calcinosis. Moreover, 9 (72.7%) of the 16 patients with panniculitis were positive for antibodies to nuclear matrix protein 2 (anti-NXP2 antibodies). Conclusion: The data showed that panniculitis is an uncommon skin manifestation in adult patients with DM, with a positivity rate of 7.8%. The appearance of panniculitis is likely associated with anti-NXP2 antibodies.