What is the relationship between leukopenia and Systemic Lupus Erythematosus (SLE)?

From the Guidelines

Leukopenia is a common manifestation of Systemic Lupus Erythematosus (SLE).

Relationship between Leukopenia and SLE

• Leukopenia is often associated with SLE, but it rarely requires treatment 1.
• The presence of anti-double-stranded DNA (anti-dsDNA) antibodies is associated with leukopenia, as well as lupus nephritis 1.
• Severe leucopenia has been linked to an increased risk of infections in patients with SLE 1.

Clinical Considerations

• A careful work-up is recommended to exclude other causes of leucopenia, such as drug-induced leucopenia 1.
• The treatment of leucopenia in SLE patients typically focuses on managing the underlying disease activity, rather than the leucopenia itself.
• Monitoring of patients with SLE should include laboratory assessments, such as complete blood counts, to detect any changes in blood cell counts, including leucopenia 1.

From the Research

Relationship Between Leukopenia and Systemic Lupus Erythematosus (SLE)

• Leukopenia is a common finding in SLE, with a prevalence ranging from 22-41.8% of cases 2.
• Lymphopenia is also common in SLE, with a cumulative prevalence of 15-82% of patients, while neutropenia is described in 20-40% of patients 2.
• The presence of leukopenia at any time is not a risk factor for severe infection in SLE, however, some studies found a strong association between low lymphocytes/neutrophils count and the risk of major infections 3, 2.
• Lymphopenia is associated with disease severity in patients with SLE, and the degree of reduction in blood cell count is also remarkable 4.
• The serum complement system and hematological profile in SLE are independently linked, after adjustment for disease activity and damage, with negative relationships found in lymphocytes 5.

Clinical Characteristics of Leukopenia in SLE

• The median leukocyte count in the leukopenia group was 2.80 × 109/l, the median neutrophil count in the neutropenia group was 1.40 × 109/l, and the median lymphocyte count in the lymphopenia group was 0.60 × 109/l 4.
• Independent risk factors for neutropenia include decreased platelet count and lymphocyte count, as well as the presentation of cylindruria 4.
• For lymphopenia, the independent risk factors were positivity for anti-dsDNA antibody and Coombs' test, decreased platelet count, and cylindruria 4.

Association with Disease Activity and Treatment

• Lymphopenia was associated with overall disease activity, ESR, serology, prednisolone, AZA, MTX, tacrolimus, CYC, and rituximab use 6.
• MTX and ciclosporin were negatively associated with neutropenia 6.
• Lupus low disease activity state was negatively associated with both lymphopenia and neutropenia 6.