What are the differences between the American College of Rheumatology (ACR) and Systemic Lupus International Collaborating Clinics (SLICC) diagnostic criteria for Systemic Lupus Erythematosus (SLE), and which is more suitable for low-resource settings with limited laboratory access?

From the Guidelines

The American College of Rheumatology (ACR) criteria is more suitable for low-resource settings with limited laboratory access due to its reliance on clinical examination findings and fewer laboratory tests. The ACR criteria, originally developed in 1982 and revised in 1997, requires 4 out of 11 criteria for diagnosis, focusing on clinical manifestations like malar rash, discoid rash, photosensitivity, oral ulcers, arthritis, serositis, renal disorder, neurologic disorder, hematologic disorder, immunologic disorder, and antinuclear antibodies 1. In contrast, the Systemic Lupus International Collaborating Clinics (SLICC) criteria, introduced in 2012, requires either 4 out of 17 criteria (with at least one clinical and one immunologic criterion) or biopsy-proven lupus nephritis with positive ANA or anti-dsDNA. The key differences between the two criteria include SLICC's requirement for both clinical and immunologic involvement, its inclusion of more laboratory parameters, and its allowance for lupus nephritis as a stand-alone criterion.

Some of the key points to consider when choosing between the ACR and SLICC criteria in low-resource settings include:

• The ACR criteria's emphasis on visible manifestations like skin rashes, oral ulcers, and arthritis that can be identified through physical examination, making it more practical in settings with limited access to extensive laboratory testing 1.
• The SLICC criteria's requirement for more laboratory tests, including anti-dsDNA and ANA, which may not be readily available in low-resource settings.
• The importance of clinical judgment and physical examination in diagnosing SLE, particularly in settings where laboratory testing is limited.

In terms of morbidity, mortality, and quality of life, the ACR criteria's focus on clinical features gives it better utility for diagnosis based primarily on clinical examination, which is critical in low-resource settings where laboratory testing may not be readily available 1. Additionally, the ACR criteria's emphasis on clinical manifestations can help identify patients with SLE who require prompt treatment, which can improve outcomes and reduce morbidity and mortality.

The use of the ACR criteria in low-resource settings can be further supported by the fact that it has been widely used and validated in various clinical settings, including those with limited laboratory access 1. Furthermore, the ACR criteria's simplicity and ease of use make it a practical choice for clinicians working in low-resource settings, where resources and expertise may be limited.

Overall, the ACR criteria is the more suitable choice for low-resource settings with limited laboratory access, due to its emphasis on clinical examination findings and fewer laboratory tests, which can help improve diagnosis and treatment outcomes for patients with SLE.

From the Research

Differences between ACR and SLICC diagnostic criteria for SLE

• The American College of Rheumatology (ACR) and Systemic Lupus International Collaborating Clinics (SLICC) diagnostic criteria for Systemic Lupus Erythematosus (SLE) have distinct differences in their classification systems 2.
• The SLICC 2012 criteria have been shown to be more sensitive than the ACR 1997 criteria in real-life clinical practice in SLE, allowing for earlier diagnosis in patients with shorter disease duration 2.
• The ACR 1997 criteria have higher specificity compared to the SLICC 2012 criteria, which may lead to fewer false positives 3.

Suitability for low-resource settings with limited laboratory access

• The SLICC 2012 criteria may be more suitable for low-resource settings with limited laboratory access, as they allow for the classification of SLE based on clinical manifestations and immunological criteria, which can be assessed without extensive laboratory testing 2, 4.
• The SLICC criteria have been shown to be effective in diagnosing SLE in patients with autoimmune cytopenia, a common manifestation of SLE in children, and may be more effective in this population compared to the EULAR/ACR 2019 criteria 4.
• However, the EULAR/ACR 2019 criteria have been externally validated in numerous studies and have become the gold standard inclusion criterion for SLE clinical trials, suggesting that they may still be useful in low-resource settings with limited laboratory access, particularly if the maximum weight of hematological involvement is increased to 6 4, 5.