In which of the following combinations of auto antibodies are both antibodies used in the diagnosis of the same autoimmune disease?
High-Yield Explanation
Anti-Smith (Sm) and anti-double-stranded DNA antibodies are both used in the diagnosis of systemic lupus erythematosus (SLE). Anti-Sm (Smith) antibodies are less sensitive (30%) than anti-double-stranded DNA (60% to 70%), but are more specific (100%). Regarding the other choices: Anti-SS-A (Ro) antibodies are positive in Sjogren syndrome and anticentromere antibodies are positive in CREST syndrome. Anti-ribonucleoprotein has a high specificity for mixed connective tissue disease. Anti-histone antibodies have a high specificity (> 95%) in drug-induced SLE. Anti-SS-B (La) antibodies have a high specificity (60%-90%) for Sjogren syndrome. Anti-single-stranded DNA antibodies are commonly seen in drug-induced SLE. Anti-mitochondrial antibodies have a high specificity for primary biliary cirrhosis. Anti-microsomal antibodies are seen in Graves disease and Hashimoto's thyroiditis. Ref - Harrison's principles of internal medicine 20e pg 2515, 2516f, 2517t, 2518t, 2522