The 1982 criteria for the classification of SLE. A diagnosis of SLE can be made with 98% specificity and 97% sensitivity if four of the criteria listed below are present at any time5
| Diagnostic criteria of the American Rheumatism Association | Patient 1 | Patient 2 |
|---|---|---|
| Malar rash | — | Yes |
| Discoid rash | — | — |
| Photosensitivity | — | |
| Oral ulcers | — | Yes |
| Arthritis (non-erosive arthritis involving two or more peripheral joints, characterised by tenderness, swelling, or effusion) | Yes | — |
| Serositis (pleuritis or pericarditis) | Yes | — |
| Renal disorder (proteinuria > 5.0 g/dl or 3+ protein, or cellular casts) | Yes | — |
| Neurological disorder | — | — |
| Haematological disorder (haemolytic anaemia, leukopenia, lymphopenia, or thrombocytopenia) | Yes | Yes |
| Immunological disorder (positive LE cell preparation or anti-dsDNA or anti-Sm antibodies or false positive VDRL) | Yes | Yes |
| Antinuclear antibodies | Yes | Yes |