Background/Purpose:

EULAR and ACR have
jointly funded a project to improve existing classification criteria for SLE;
this abstract reports on the early phase of this project.  Classification criteria are being
developed using multicriteria decision analysis methods.  The goal of the initial phase of this
project was to generate a broad set of items potentially useful for the
classification of SLE and select a list of candidate items for use in
forced-choice decision analysis.  The aims were to include items that encompass a broad
spectrum of SLE, including patients whose disease is in the early stage as well
as those in the late stage, and that are in accordance with criteria used for
diagnosis of SLE in clinical practice.

Methods:

135 expert lupus clinicians were asked to independently rate
items derived from the ACR and SLICC classification criteria for their
importance in diagnosing early and established SLE, respectively, in an online
survey.  Answers were retrieved from
120 experts (N= 54 from EULAR centres, 
n=66 from North American). In addition, open commentary fields were
provided for the suggestion of novel items.

Results:

Interestingly, while 58% of those would not diagnose SLE
without a positive ANA by immunofluorescence on at least one occasion, 23% said
they would make a diagnosis and 19% were unsure.  The experts were in agreement that
characteristic autoantibodies as well as specific renal features and skin
manifestations are key for diagnosing SLE, regardless of whether early or
established SLE.  When asked about
organ system involvement, 51,1% stated that one organ system would been
sufficient for making the diagnosis of SLE, but that additional typical
laboratory features (ANA, dsDNA) would be required.

Notably, 85% of the expert group would make the diagnosis of
SLE if renal pathology shows lupus nephritis, but skin histology was not rated
nearly as specific.

Conclusion:

A survey of international SLE experts indicates that they
consider a broad range of items for the diagnosis of SLE.  Nevertheless, it is interesting that a
majority would diagnose SLE based only on renal pathology, as suggested by the
SLICC group, as well as upon single organ system involvement in the presence of
additional laboratory findings such as ANA and dsDNA.  These ideas will be explored in more
detail in the next phases of the project.

Table 1: