Objective Analysis and evaluation of cystatin C (Cysc) ,N‐acetyl‐beta‐D‐glucosaminidase (NAG) ,β2‐microglobulin (β2‐MG) ,blood urea nitrogen(BUN) ,serum creatinine(Scr) five biological parameters in the diagnosis of early renal damage caused by the diseases of Systemic lupus eythematosus ,diabetes or high blood pressure .Methods Collecting 61 patients with high blood pressure ,62 patients with systemic lupus eythematosus (SLE) ,59 patients with diabetes ,56 cases of healthy controls .Cysc was e‐valuated by immune transmission turbidimetric method ,latex enhanced immune turbidimetric method was used to detectβ2‐MG ,u‐sing two point method to determine NAG ,enzymatic assay Scr ,UV‐GLDH method was used to measure serum BUN ,and using the statistical method to analyze the data .Results There was no significant difference between healthy controls and patients group (P>0 .05) in BUN and Src levels .However ,there were significant differences in Cysc ,urineβ2‐MG and NAG concentrations (P<0 .01) .Under ROC curve ,the largest square of diagnosis indexes for early renal damage caused by SLE ,diabetes ,high blood pres‐sure were blood NAG ,urineβ2‐MG and Cysc .Compared to a single parameter ,the rate of joint detection in the diagnosis of early re‐nal damage is high ,a joint detection of Cysc ,β2‐MG and urine NAG could enhance the positive rate to 88 .7% ,which was signifi‐cantly higher than the joint detection with two indexes (77 .4% ,70 .9% or 66 .1% ) .Conclusion The most sensitive and specific in‐dex in the diagnosis of early renal damage caused by SLE ,diabetes ,high blood pressure were blood respectively NAG ,urine beta 2‐MG and Cysc .Joint detection has higher detection rate ,sensitivity ,specificity ,and has important clinical value in the early diagnosis of patients with renal damage ,which is suitable for clinical application .

Objective To screen the mutations in 30 exons of COL4A5 gene from X-linked Alport syndrome. Methods 20 Chinese X-linked Alport syndrome patients from 16 families were examined. Genomic DNA was extracted from peripheral leukocyte and exon-specific primers were designed for 30 exons(1-25、31、 32、41、 50、51) . Polymerase chain reaction amplification was performed and followed bydegenerating gel gradient electrophoresis (DGGE) analysis. All abnormal migration bands were sequenced and one hundred normal persons selected as control. Results Four abnormal bands were detected, which were all point mutations and predicted to be functionally pathogenic, in four unrelated patients. One patienthad a nonsense mutation in exon 1 (Glu 22 Term); one had a missense mutation in exon 3l(Gly852Val).Two patients carried splicing mutations in intron 1 and 25 respectively(283+1G→T、2150 + 1G→T) .Conclusions X-linked Alport syndrome is caused by various kinds of COL4A5 gene mutations without any hotspot. Paralleled with the significance of exon mutations, intron mutations also play a critical role in the pathogenesis. Furthermore, these four pathogenic mutations have never been reported in the genebank and showed good correlation with clinical manifestations.