Assessment of disease activity and damage in SLE: Are we there yet?

: Systemic Lupus Erythematosus is a systemic autoimmune disease characterized by a great heterogenicity in course and clinical manifestations. Although prognosis improved in the last decades of the 20th century, mortality remains higher than in the general population and uncontrolled disease activity and therapy-related adverse effects have been identified as major contributors to damage accrual and poor outcomes. Assessment of disease activity and damage in SLE represents a great challenge even to the expert rheumatologist. Global disease activity indices are tools developed to assess activity across multiple organ systems. Several disease activity indices have been developed over the years, each with its own strengths and weaknesses, and knowing them is essential for understanding research studies, such as clinical trials, in which they are used. Organ-specific activity indices have been developed concurrently to represent organ involvement such as glomerulonephritis, cutaneous and musculoskeletal lupus manifestations. Regarding damage, the SLICC/ACR damage index has proven to be an effective tool for damage accrual assessment, yet not devoid of drawbacks. This review provides an overview of the most frequently utilized indices developed for the assessment of activity and damage in SLE highlighting their pros and cons when applied to the research and clinical setting.