[Systemic lupus erythematosus and lymphopenia: Clinical and pathophysiological features]

Area of Science:

• Immunology
• Rheumatology
• Clinical Medicine

Background:

• Lymphopenia is common in systemic lupus erythematosus (SLE), affecting T lymphocytes more than B cells.
• Profound lymphopenia (<500/mm³), seen in 10% of SLE cases, has complex underlying mechanisms.
• Mechanisms include lymphocytotoxic antibodies, apoptosis, complement-mediated lysis, impaired lymphopoiesis, and lymphocyte sequestration.

Purpose of the Study:

• To investigate the characteristics and implications of lymphopenia in SLE patients.
• To analyze the association of lymphopenia with disease activity, flares, and damage.
• To evaluate the infectious risk associated with lymphopenia in SLE.

Main Methods:

• Review of existing literature and clinical data on SLE patients with lymphopenia.
• Analysis of factors contributing to lymphopenia, including immunological and cellular processes.
• Correlation of lymphopenia severity with disease outcomes and infection rates.

Main Results:

• Lymphopenia in SLE is independent of other cytopenias and drug regimens.
• It correlates with increased disease activity, risk of flares, and damage scores.
• Lymphopenia (<1 G/L) is an independent risk factor for severe bacterial infections; T-cell deficiency impacts viral control.

Conclusions:

• Management strategies for SLE with lymphopenia are not well-defined.
• Infectious prophylaxis should be considered on a case-by-case basis.
• Profound lymphopenia in SLE may represent a distinct subset with primary immunodeficiency requiring tailored care.