Systemic lupus erythematosus with negative LE cells and antinuclear factor

Area of Science:

• Rheumatology
• Immunology
• Dermatology

Background:

• Systemic Lupus Erythematosus (SLE) is a complex autoimmune disease.
• Diagnosis typically relies on specific serological markers like antinuclear factor (ANF) and LE cells.
• Atypical presentations of SLE can pose diagnostic challenges.

Purpose of the Study:

• To identify and characterize a subgroup of patients with active SLE who persistently lack ANF and LE cells.
• To delineate the unique clinical and immunological features of this SLE variant.

Main Methods:

• Prospective study of 165 patients with SLE.
• Identification of a subgroup (n=8) with active disease but negative ANF and LE cell tests.
• Clinical assessment including skin rash, arthritis, renal function, and lupus band test.
• Serological testing for antibodies to DNA and cytoplasmic antigens.

Main Results:

• Eight patients with active SLE exhibited persistently negative ANF and LE cell tests.
• This subgroup showed a photosensitive skin rash and negative lupus band test.
• High incidence of arthritis and mild renal disease were noted.
• A positive family history for connective tissue disease was common.
• Antibodies to DNA and cytoplasmic antigens were detected in a minority.

Conclusions:

• A distinct subset of SLE patients may present with active disease despite negative ANF and LE cell tests.
• Clinical phenotype, including photosensitive rash, arthritis, and mild renal involvement, aids in identifying these cases.
• Further research is needed to understand the immunopathogenesis of ANF/LE cell-negative SLE.