Autoimmunity—Identify the Disease Which of the following is an autoimmune disease characterized by multisystem involvement and autoantibodies (e.g., anti-dsDNA, anti-Sm)?

Introduction / Context:
Autoimmune diseases arise when immune tolerance fails and self-reactive lymphocytes cause tissue damage. Systemic lupus erythematosus (SLE) is a prototypical systemic autoimmune disease with diverse clinical features and hallmark autoantibodies. This item differentiates autoimmune disease from infectious diseases and immunodeficiency syndromes.

Given Data / Assumptions:

• SLE involves immune complex deposition and complement activation.
• AIDS results from HIV infection and progressive immunodeficiency, not autoimmunity.
• Measles, mumps, influenza are viral infections, not autoimmune disorders.

Concept / Approach:
Identify which option depicts an autoimmune pathology rather than an infection or immunodeficiency. SLE uniquely fits, with chronic relapsing disease, multi-organ involvement (skin, kidneys, joints, CNS), and serologies such as ANA, anti-dsDNA, and anti-Sm antibodies.

Step-by-Step Solution:

Verification / Alternative check:
Diagnostic criteria include clinical and immunologic domains; serologic testing often reveals anti-dsDNA with low complement levels during flares.

Why Other Options Are Wrong:

• AIDS: acquired immunodeficiency, not autoimmune.
• Measles/Mumps/Influenza: acute viral infections.

Common Pitfalls:
Equating chronicity with autoimmunity; many chronic infections are not autoimmune.

Final Answer:
Lupus (systemic lupus erythematosus)