The American College of Rheumatology ( ACR ) established 11 criteria in 1982, which were revised in 1997 as a classificatory instrument to operationalise the definition of SLE in clinical trials. They were not intended to be used to diagnose individuals and do not do well in that capacity.
For the purpose of identifying patients for clinical studies, a person has SLE if any 4 out of 11 symptoms are present simultaneously or serially on two separate occasions.
1. Serositis: Pleuritis (inflammation of the membrane around the lungs) or pericarditis (inflammation of the membrane around the heart); sensitivity = 56%; specificity = 86% (pleural is more sensitive; cardiac is more specific).
2. Oral ulcers (includes oral or nasopharyngeal ulcers).
3. Arthritis: nonerosive arthritis of two or more peripheral joints, with tenderness, swelling, or effusion; sensitivity = 86%; specificity = 37%.
4. Photosensitivity (exposure to ultraviolet light causes skin rash, or other symptoms of SLE flareups); sensitivity = 43%; specificity = 96%.
5. Blood—hematologic disorder—hemolytic anemia (low red blood cell count) or leukopenia (white blood cell count<4000/µl), class=”mw-redirect”>lymphopenia (<1500/µl) sensitivity =” 59%;” specificity =””>
6. Renal disorder: More than 0.5g per day protein in urine or cellular casts seen in urine under a microscope; sensitivity = 51%; specificity = 94%.
7. Antinuclear antibody test positive; sensitivity = 99%; specificity = 49%.
8. Immunologic disorder: Positive anti-Smith, anti-ds DNA, antiphospholipid antibody, and/or false positive serological test for syphilis; sensitivity = 85%; specificity = 93%. Presence of anti-ss DNA in 70% of cases (though also positive with rheumatic disease and healthy persons)
9. Neurologic disorder: Seizures or psychosis; sensitivity = 20%; specificity = 98%.
10. Malar rash (rash on cheeks); sensitivity = 57%; specificity = 96%.
11. Discoid rash (red, scaly patches on skin that cause scarring); sensitivity = 18%; specificity = 99%.
The mnemonic to remember the 11 symptoms is ‘SOAP BRAIN MD’.
Some people, especially those with antiphospholipid syndrome, may have SLE without four criteria, and also SLE may present with features other than those listed in the criteria.