Background: Pediatric systemic lupus erythematosus (pSLE) accounts for
about 20% of all cases of Systemic Lupus Erythematosus (SLE), with
nephritis occurring in approximately 50% of the patients. Objective: to
evaluate the expression of CXCR3 in the kidneys and on CD4+ T cells in
pSLE. Methods: This study was conducted on 45 patients with pSLE
following up at the Allergy and Immunology Clinic, Children's Hospital, Ain
Shams University and 45 age and sex matched healthy children as a control
group. Medical history, clinical examination and routine laboratory
investigations for assessment of disease activity were done for all patients,
the frequency of CXCR3, CD4+ T cells was determined in all patients and
controls. Twenty-five Paraffin blocks of patients with lupus nephritis (LN)
(available at the time of the study) underwent immunohistochemistry
staining for the frequencies of Chemokine C receptor (CXCR3). Results:
The absolute level and percentage of serum CD4+CXCR3+ were
significantly lower among our patients as compared to healthy controls. A
significant direct correlation was found between serum CD4+CXCR3+ and
both the lymphocytic count and quantitative Systemic Lupus erythematosus
disease activity index (SLEDAI), as well as a significant inverse correlation
between it and 24 hours urinary proteins. Variable degrees of CXCR3
expression seemed to have no impact on laboratory tests, British Isles Lupus
Assessment Group (BILAG) score and cumulative doses of
Immunosuppressives. Conclusion: Serum CD4+CXCR3+ and not renal
CXCR3 may be a potential marker of LN activity.