How laboratories define a serological hallmark of systemic lupus erythematous and which assays they use to detect it could contribute to misclassification of patients identified as anti-nuclear antibody (ANA) negative, according to researchers. Most people who have lupus test positive for ANAs as part of an immunology screening for autoimmune disorders. The presence of ANAs…
![](https://www.the-rheumatologist.org/wp-content/uploads/2019/10/THR_1019_pg49a-150x150.png)