Distinctive cutaneous and systemic features associated with antitranscriptional intermediary factor-1γ antibodies in adults with dermatomyositis

Background: Antibodies against transcriptional intermediary factor (TIF)-1 gamma are associated with malignancy in dermatomyositis (DM). Identification of clinical findings associated with anti-TIF-1 gamma antibodies in DM is a high priority for both patient diagnosis and risk assessment. Objective: We sought to define the clinical phenotype of patients with anti-TIF-1 gamma DM. Methods: Using a novel, sensitive, and specific assay for anti-TIF-1 gamma antibodies, we retrospectively tested plasma from 134 adult patients with DM and examined associations between anti-TIF-1 gamma antibodies and particular clinical and laboratory features. Results: In all, 55 (41%) patients had autoantibodies to TIF-1 gamma. Anti-TIF-1 gamma positive patients were less likely to have systemic features including interstitial lung disease, Raynaud phenomenon, and arthritis/arthralgia. Patients with TIF-1 gamma autoantibodies had more extensive skin involvement, and some patients manifested characteristic findings including palmar hyperkeratotic papules, psoriasis-like lesions and a novel finding of hypopigmented and telangiectatic ("red on white'') patches. Limitations: This was a retrospective study from a single tertiary referral center. Conclusion: TIF-1 gamma is the most commonly targeted DM-specific autoantigen in adults in a large US cohort. Although these patients tend to have less systemic involvement, their skin disease is often extensive and characteristic. Recognition of cutaneous findings in anti-TIF-1 gamma positive patients may allow more accurate and timely diagnosis and effective treatment of patients with DM.