Systemic lupus erythematosus (SLE) is a chronic, multisystem autoimmune disease characterized by loss of immune tolerance, autoantibody production, immune complex deposition, and complement activation, resulting in widespread inflammation and organ damage. Renal involvement, known as lupus nephritis (LN), occurs in approximately 40-60% of SLE patients and represents one of the most severe disease manifestations, significantly contributing to morbidity and mortality.Lupus nephritis arises from immune complex deposition in glomerular and tubulointerstitial structures, causing inflammatory and proliferative lesions that can progress to chronic kidney disease or end-stage renal disease. The ISN/RPS classification provides a standardized histopathological framework essential for prognosis and guiding treatment decisions.

In addition to renal complications, patients with SLE and LN are at substantially increased risk of premature cardiovascular disease, which cannot be fully explained by traditional cardiovascular risk factors.Persistent systemic inflammation, endothelial dysfunction, dyslipidemia, and insulin resistance accelerate atherosclerosis in these patients. Subclinical vascular changes, including increased carotid intima-media thickness (CIMT) and carotid plaque formation, often precede overt cardiovascular events, underscoring the importance of early cardiovascular risk assessment The triglyceride-glucose (TyG) index is a validated surrogate marker of insulin resistance, correlating with endothelial dysfunction, subclinical atherosclerosis, and increased CIMT Elevated TyG index may therefore serve as a simple, non-invasive tool for early cardiovascular risk stratification in patients with lupus nephritis