[Seronegative antiphospholipid syndrome: Myth or reality?]

Area of Science:

• Rheumatology
• Immunology
• Autoimmune Diseases

Background:

• Antiphospholipid syndrome (APS) is an autoimmune disorder causing thrombosis and pregnancy issues.
• Diagnosis relies on persistent antiphospholipid antibodies (aPL), including lupus anticoagulant (LA), anticardiolipin (ACL), and anti-β2 glycoprotein I (aβ2GPI).
• A subset of patients presents APS symptoms but lacks these conventional aPL markers, leading to the concept of seronegative APS.

Purpose of the Study:

• To explore the concept and diagnostic criteria for seronegative APS.
• To review emerging antigen targets and methodologies for identifying seronegative APS.
• To discuss the current status and future research directions for seronegative APS.

Main Methods:

• Review of current literature on antiphospholipid syndrome and seronegative APS.
• Analysis of emerging diagnostic markers and techniques for aPL detection.
• Discussion of clinical evidence and ongoing research in the field.

Main Results:

• Seronegative APS is increasingly recognized in patients with clinical APS features but negative conventional aPL tests.
• New antigen targets and improved methodologies are being developed to identify these patients.
• The clinical relevance and diagnostic standardization of non-conventional aPL are still under investigation.

Conclusions:

• Seronegative APS represents a distinct subgroup of APS, though still debated.
• Further standardization of diagnostic tools and large-scale longitudinal studies are crucial.
• Confirming the clinical significance of non-conventional aPL is essential for advancing seronegative APS diagnosis and management.