New Blood Tests Approved for Lupus, Systemic Sclerosis Diagnoses

Carolyn Crist

June 17, 2022

The Food and Drug Administration has approved a new diagnostic blood test to detect monospecific Ribosomal P antibodies to support a diagnosis of systemic lupus erythematosus (SLE), particularly for people who are antinuclear antibody-negative, according to a recent announcement from the test developer, Thermo Fisher Scientific Inc.

The company also said the agency approved a separate blood test for RNA Polymerase III antibodies to support a diagnosis of systemic sclerosis (SSc), or scleroderma. RNA Polymerase III antibodies are a criteria marker for SSc with both diagnostic and prognostic value.

The company noted that a subset of patients with SLE present with ribosomal P antibodies, and the new test, called EliA Rib-P, aims to improve on the "unreliable method" of detecting these antibodies via indirect immunofluorescence, "which if used solely, could result in delayed diagnosis and treatment."

The company also noted that up to 70% of patients who test positive for RNA Polymerase III antibodies with the SSc test, called EliA RNA Pol III, have no other SSc-associated antibodies. The test also "completes a criteria-based EliA SSc panel and is the first fully automated RNA Polymerase test available" in the United States.

"The availability of a strong CTD test menu on a fully automated instrument could improve the efficiency and productivity of diagnostic laboratories," Dr Henry Homburger, Professor Emeritus of Laboratory Medicine at Mayo Clinic College of Medicine, and laboratory director, Thermo Fisher Phadia Immunology Reference Laboratory, said in the announcement. "The new EliA RNA Pol III and EliA Rib-P tests have been designed to improve the differentiation of SSc and SLE from other connective tissue diseases. Targeting existing diagnostic care gaps can potentially lead to earlier and more accurate diagnosis and ultimately improve clinical outcomes for patients."


Lupus Foundation of America: "New Blood Test Approved for Lupus Diagnosis."

Thermo Fisher Scientific: "FDA Clears Thermo Scientific EliA RNA Pol III and EliA Rib-P Tests for Use in U.S."


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