Background Glomerulonephritis and renal failure represent one of the most life-threatening manifestations of systemic lupus erythematosus. Many patients show persistent proteinuria despite conventional therapy (anti-inflammatory and immunosuppressive therapies). ƒ. Vitamin D is immune modulator thought to be a potent inhibitor of the RAAS (renin–anigotensin–aldosterone system) which increase in kidney damage. Vitamin D deficiency is common in systemic lupus erythematosus. So Correcting vitamin D deficiency may play important role for treatment lupus nephritis

Aim The aim of This study will detect t the potential role of high supplementation of vitamin D therapy as anti-proteinuric effects in the treatment of lupus nephritis on conventional therapy with persistent proteinuria.

Patients and methods Ninty patients with with lupus nephritis and persistent proteinuria despite conventional therapy will be recruited. They will be treated with vitamin D and follow up for 24 months. Proteinuria, renal function, lupus disease activity, serum and urinary inflammatory markers and urinary angiostatin will be monitored. the mean vitamin D in the patient group was 10.7+7.9 ng/ml. vitamin D supplementation depend on severity of deficient and weight of patient s. twenty five patients with lupus nephritis without vitamin D supplementation as control group.

Results Our results show that reduction in protinuria as measured by urinary protien creatinine (UP/C) ratio in 24 hour collection at 12 (r,0.61. p<0.001), and 24 weeks (r, 0.65. p<0.001), compared with base line, all patients completed all 24 weeks of study treatment. Improvement of median proteiuria reduction from base line was 64.2% at 12 weeks and 88%at 24 weeks. Serum vitamin D levels were inversely associated with the urinary protein creatinine UP/C ratio (p<0.001) and urinary vit D binding protein DBP/C (p<0.001).

Conclusions Our findings show that new strategy of adding vitamin D therapy as new treatment for 24 weeks to maintain optimal serum 25(OH) D levels and diminish proteinuria in lupus nephritis patients. We need longer duration and more studies to confirm our results from different countries.