Specialists will use their experience and classification criteria, that were initially designed for scientific research purposes, to build their diagnosis.
The international scientific community has defined classification criteria to enable the diagnosis of systemic lupus. Two main classifications have been proposed (see Annex 2).
That of the American College of Rheumatology (ACR), which has 11 criteria.
The presence of at least 4 of these 11 criteria makes it possible to classify a patient as suffering from systemic lupus.
The 2019 ACR/EULAR criteria where a patient can be classified Systemic Lupus when (s)he reaches a score of 10 or more if the entry criterion is fulfilled.
The diagnosis of lupus is based on the comparison of the clinical and biological signs of the disease.
A formal diagnosis can sometimes take several months.