This case-control study aims to explore the relationship between specific blood indices (lymphocyte-monocyte ratio, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and systemic immune-inflammatory index) and disease activity in patients with systemic lupus erythematosus (SLE).

The study includes 70 SLE patients and 70 healthy controls, matched for age and gender, recruited from Assiut University Hospital.

Disease activity is assessed using the SLEDAI-2K score, and blood indices are analyzed to determine correlations with disease activity.

This case-control study will be conducted at Assiut University Hospital, involving 70 patients diagnosed with SLE according to the 2019 ACR/EULAR classification criteria and 70 healthy controls matched for age and gender. Inclusion criteria include patients aged 18 years or older with SLE, while exclusion criteria include other autoimmune diseases, recent infections, and hematological disorders unrelated to SLE.

Study Tools and Procedures:

Demographic Information: Collect data on age, gender, duration of illness, and relevant medical history.

Clinical Assessment: Disease activity will be evaluated using the SLEDAI-2K score, which includes parameters such as mucocutaneous manifestations, musculoskeletal symptoms, renal involvement, neurological symptoms, and hematological abnormalities.

Laboratory Tests: A complete blood count (CBC) will be performed to obtain lymphocyte, monocyte, neutrophil, and platelet counts. Additional tests may include serum creatinine levels, urinalysis for proteinuria, 24-hour urinary proteins, CRP, ESR, and complement levels (C3, C4) to assess overall disease status.

Study Tools: The SLEDAI-2K tool will categorize patients based on their disease activity levels. CBC results will be analyzed to calculate LMR, NLR, PLR, and SIRI, which will be correlated with the SLEDAI-2K score.

Research Outcome Measures Primary Outcome: The primary objective is to assess the correlation between blood indices (LMR, NLR, PLR, SIRI) and SLE disease activity as measured by the SLEDAI-2K score. This will involve statistical analysis to determine if there is a significant correlation between these indices and disease activity.

Secondary Outcomes:

Comparison of Blood Indices: Evaluate differences in LMR, NLR, PLR, and SIRI between SLE patients and healthy controls.

Disease Activity Variability: Analyze how variations in blood indices correlate with changes in SLEDAI-2K scores over time.

Exploration of Additional Hematological Indices: Investigate other hematological parameters such as mean platelet volume (MPV) to determine their association with disease activity.

Impact of Treatment: Assess how treatment interventions affect blood indices and correlate these changes with improvements or deteriorations in SLEDAI-2K scores.

Inclusion Criteria:

• Patients aged 18 years or older diagnosed with SLE according to the 2019 ACR/EULAR classification criteria.
• Healthy controls without any autoimmune diseases or significant comorbidities

Exclusion Criteria:

• • Patients with other autoimmune diseases (e.g., rheumatoid arthritis, Sjögren's syndrome).

  • Recent infections or acute inflammatory conditions.
  • Individuals with hematological disorders unrelated to SLE (e.g., leukemia, lymphoma).

cases are Patients aged 18 years or older diagnosed with SLE according to the 2019 ACR/EULAR classification criteria and • Healthy controls without any autoimmune diseases or significant comorbidities