An antibody to Sm, a ribonucleoprotein found in the nucleus of a cell, is found almost exclusively in people with lupus. It is present in 20-30% of people with the disease, but it is rarely found in people with other rheumatic diseases and its incidence in healthy individuals is less than 1%. Therefore, it can also be helpful in confirming a diagnosis of systemic lupus. Unlike anti-dsDNA, anti-Sm does not correlate with the presence of kidney lupus.
Anti-Smith antibody testing should be considered in people with signs or symptoms of SLE or MCTD, such as the following:
- Malar rash
- Discoid rash
- Mucosal ulcers
- Avascular necrosis
Anti-Smith antibodies are present in some cases of systemic lupus erythematosus (SLE) and mixed connective-tissue disease (MCTD).
- Anti-Smith antibody is more common in blacks and Asians with SLE than in whites with SLE.
- Elevated anti-Smith levels persist even after anti-DNA levels have returned to the normal range. This is useful when testing with decreased signs or symptoms of SLE (ie, a waning phase).
Own it for life
Our exclusive data entry service is a convenient way to get your results into your private dashboard. Simply attach an image or a file of your lab test results, and one of our qualified data entry team members will add the results for you. We support all sorts of files, whether PDFs, JPGs, or Excel. This service is excellent whether you have a lot of reports to upload or are too busy to do the data entry yourself.
We strive to make the data entry process easy for you. Whether by offering dozens of templates to choose from that pre-populate the most popular laboratory panels or by giving you instant feedback on the entered values. Our data entry forms are an easy, fast, and convenient way to enter the reports yourself. There is no limit on how many lab reports you can upload.
billed every month
Data entry included
$6.60/month billed annually
Data entry included
own it for life
Are You a Health Professional?
Get started with our professional plan
Welcome to Healthmatters Pro.
Save time on interpreting lab results with the largest database of biomarkers online. In-depth research on any test at your fingertips, all stored and tracked in one place. Learn more
Pro Monthly Plus
for health professionals
$75 per month