Platlet to Lymphocyte Ratio and Neutrophils to Lymphocyte Ratio as potential Markers For Lupus Nephritis Flares

Abstract

Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory disease with unknown etiology and diversity of clinical manifestations, course of illness and prognosis. Many laboratory parameters can be used to check for disease activity such as low complement and increased deoxyribonucleotide (DNA) binding. Lupus nephritis (LN) is one of the commonest and most serious manifestations of SLE leading to significant morbidity and mortality among patients. It affects nearly 50% of SLE patients, leading to increasing the risk of renal failure and cardiovascular diseases. Early diagnosis and rapid treatment of lupus nephritis are crucial to improve survival in SLE patients. Renal biopsy is still the standard investigation to check for suspected flares in lupus nephritis. The renal biopsy carries some risks, primarily of bleeding resulting in perirenal hematoma and blood transfusion. Searching for simple laboratory indicators that are available in almost every healthcare facility to evaluate disease activity and renal affection in SLE patients is an important issue .The type of circulating WBCs exhibits certain changes in systemic inflammation, which is mainly characterized by neutrophilia and lymphopenia. Clinicians use the changes in peripheral blood cell components as in autoimmune and nonautoimmune disorders as a predictor of immunological activity. The most significant components of the complete blood count (CBC) is the platelet-to-lymphocyte (PLR) and neutrophil-to lymphocyte (NLR) ratios. Platelet system activation is a key event in the pathogenesis of SLE. Circulating immune complexes, anti-phospholipid antibodies and infectious agents such as virus are the main activators of platelets in SLE. A high NLR is used as an inflammatory marker for different autoimmune diseases such as primary Sjögren's syndrome (PSS), psoriasis and ulcerative colitis. High PLR has been used as a marker for differential diagnosis or prognostic prediction of different diseases such as cancer and inflammatory diseases.