Lupus is an autoimmune disease. Carrying out a biological assessment makes it possible to diagnose the disease and to assess its level of severity.
Lupus is a autoimmune disease that can affect multiple parts of the body. “Laboratory tests for lupus can help diagnose the disease and assess its severity“, specifies Dr. Maëva Masson, rheumatologist.
► In this exam, we first ask for the antinuclear antibody (ANA) assay. “These antibodies are present in most patients with lupus. Their dosage is mandatory for the diagnosis: if they are negative, the diagnosis is very unlikely”. Tests such as ELISA or immunofluorescence can be performed to detect the presence of ANA.
“Anti-DNA antibodies are also specific for this disease“. Tests such as ELISA or radioimmunology can be performed to detect them. “Anti-SSA/SSB antibodies are a category of anti-nuclear antibodies that can be found in lupus but also in other autoimmune diseases“. We also dose the anti-MS antibodies which are specific to lupus. Tests such as ELISA can be performed to detect them.
► Liver and kidney function tests : “lupus can affect liver and kidney function, and tests such as bilirubin, transaminases, creatinine, and urea may be done to assess these functions“. There proteinuria (or protein levels in urine) detects kidney damage.
► The inflammation tests : “lupus can cause inflammation, and assays such as CRP (C-reactive protein) and sedimentation rate (ESR) can be performed to assess inflammation“.
► The coagulation tests : “lupus can affect clotting, and tests such as prothrombin time (PT) and the activated partial thromboplastin time (aPTT) may be requested to assess coagulation function”.
It is important to note that the laboratory work-up for lupus can vary depending on the clinical presentation of the patient and the severity of the disease.
Thanks to Dr Maëva Masson, rheumatologist at Toulouse University Hospital.