Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare disorder that must be distinguished from systemic lupus erythematosus (SLE). Although a minority of patients with KFD develop SLE, most patients have a self-limited disease. Importantly, KFD can have skin manifestations resembling cutaneous lupus. Therefore, the diagnosis of SLE should be predicated on a complete rheumatologic workup and not on the constellation of skin disease and lymphadenitis. Nonetheless, as our exceedingly rare case illustrates, patients who do not initially meet diagnostic criteria for SLE require dermatologic follow-up. We present a young adult woman who had a remote history of KFD and later presented with combined features of discoid lupus and lupus erythematosus panniculitis (LEP). On subsequent rheumatologic workup, she fulfilled criteria for SLE. We discuss the differential diagnosis of both KFD and LEP and emphasize how strong communication among dermatologists and other healthcare providers is essential in the management of patients with KFD.

OBJECTIVE:The American College of Rheumatology and the European League Against Rheumatism embarked on a project to reevaluate classification criteria for systemic lupus erythematosus (SLE). The first phase of the classification project involved generation of a broad set of items potentially useful for classification of SLE and their selection for use in a subsequent forced-choice decision analysis. METHODS:A large international group of expert lupus clinicians was invited to participate in a 2-step process to generate, rate, and select items based on their importance in diagnosing early and established SLE, via a web-based survey. RESULTS:A total of 135 and 147 experts were invited to participate in the item-generation and item-reduction process, respectively. Of 145 items generated, item reduction resulted in 40 candidate items moving forward to the next phase. Key features for classifying both early and established SLE included characteristic autoantibodies, specific renal features, and skin manifestations. A small majority (51%) stated that 1 organ system would be sufficient for classifying SLE, but that additional typical laboratory features (antinuclear antibody, anti-double-stranded DNA) would be required. Notably, 85% of the expert group would positively classify SLE if renal pathology alone showed lupus nephritis. CONCLUSION:The Delphi exercise resulted in a set of 40 candidate criteria for the classification of SLE for subsequent assessment. This study comprised the largest panel ever involved in the development of SLE classification criteria, providing a broadly representative view of the current approach to classification of SLE.

Objective

To define candidate criteria within multiphase development of systemic lupus erythematosus (SLE) classification criteria, jointly supported by the American College of Rheumatology and the European League Against Rheumatism. Prior steps included item generation and reduction by Delphi exercise, further narrowed to 21 items in a nominal group technique exercise. Our objectives were to apply an evidence-based approach to the 21 candidate criteria, and to develop hierarchical organization of criteria within domains.

Methods

A literature review identified the sensitivity and specificity of the 21 candidate criteria. Data on the performance of antinuclear antibody (ANA) as an entry criterion and operating characteristics of the candidate criteria in early SLE patients were evaluated. Candidate criteria were hierarchically organized into clinical and immunologic domains, and definitions were refined in an iterative process.

Results

Based on the data, consensus was reached to use a positive ANA of ≥1:80 titer (HEp-2 cells immunofluorescence) as an entry criterion and to have 7 clinical and 3 immunologic domains, with hierarchical organization of criteria within domains. Definitions of the candidate criteria were specified.

Conclusion

Using a data-driven process, consensus was reached on new, refined criteria definitions and organization based on operating characteristics. This work will be followed by a multicriteria decision analysis exercise to weight criteria and to identify a threshold score for classification on a continuous probability scale.