Study On The Relationship Between Urinary Vitamin D Level And Lupus Nephritis

Objective:Detection of urinary 1,25?OH?₂D₃ level in systemic lupus erythematosus by ELISA,to explore the relationship between urinary 1,25?OH?₂D₃concentration and lupus nephritis.Methods:1.Urine,laboratory parameters,clinical symptoms and signs were collected from 136 SLE patients and 25 healthy subjects matched by sex and age at the same time.2.SLE with a history of lupus nephritis were defined as LN group?67cases?and the remaining SLE patients as nLN group?69 cases?.According to the 24h urinary protein quantification,LN patients were divided into active LN group(urinary protein quantification??500mg/24h?and inactive LN group?urinary protein quantification<500mg/24h?.3.Urinary 1,25?OH?₂D₃ concentration were measured by ELISA in all subjects.4.The baseline data and laboratory results between SLE patients and healthy subjects,LN and nLN,active LN and inactive LN were analyzed by SPSS.The correlation between urine 1,25?OH?₂D₃ concentration and C3,C4,SLEDAI,24h urinary protein quantification was analyzed.5.To explore the relationship between urinary 1,25?OH?₂D₃concentration and LN.Results:1.The concentration of urinary 1,25?OH?₂D₃ in SLE[27.64?22.175,34.503?ng/mL]were significantly higher than that in healthy subjects[87.62?32.615,104.13?ng/mL]?p=0.000?.2.?1?The probability of LN in male SLE was 90.9%?10/11?,45.6%?57/125?for female SLE,and the difference was statistically significant?x²=8.304,p=0.004?.?2?The course of SLE in LN group[3?1,6?years]was shorter than that in nLN group[6?2,10?years]?t=-4.218,p=0.000?.?3?The age of onset of LN?23.51±6.03 years old?was smaller than that of nLN group?37.47±6.07 years old??t=-10.073,p=0.000?.3.Urinary 1,25?OH?₂D₃ concentration in LN[26.54?19.71,32.70?ng/mL]were lower than those in nLN[28.51?24.79,79.35?ng/mL],which is statistically significant?p=0.01?.?2?The count of leukocyte,neutrophil,platelet,creatinine and SLEDAI in LN were higher than those in nLN,which is statistically significant?p<0.05?.?3?The mean volume of erythrocyte,albumin,C3 and C4 in LN were lower than those in nLN,and the difference was statistically significant?p<0.05?.4.There was no significant difference in urinary 1,25?OH?₂D₃concentration between active LN group and inactive LN group?t=-1.028,p=0.304?.5.There was no linear correlation between urinary 1,25?OH?₂D₃concentration and C3,C4,SLEDAI,24h urinary protein quantification in LN patients?p>0.05?.Conclusions:1.Urinary 1,25?OH?₂D₃ concentration in SLE patients were generally low,especially in LN patients.2.The count of leukocyte,neutrophil,platelet,creatinine and SLEDAI in LN were higher than those in nLN,and albumin,C3 and C4 levels were lower than those in nLN.3.Male SLE patients are more likely to develop lupus nephritis.