Role Of Angiotensinogen In The Progression Of Renal Injury In Henoch-Sch(?)nlein Purpura Children

ObjectiveCompare the differences of plasm angiotensinogen(PAGT)and urine angiotensinogen(UAGT)levels in Henoch-Sch?nlein purpura nephritis(HSPN)children,Henoch-Sch?nlein purpura(HSP)patients and the control group.And analyze the relationship between UAGT levels and all kinds of clinical parameters in HSPN patients.Investigate whether UAGT levels are correlated with renal involvement of HSP patients.MethodsThirty hospitalized HSPN patients,31 HSP patients were included in this study,and choose gender and age matched 25 healthy children as control group.All subjects with diseases of chronic kidney disease,chronic liver disease,the other rheumatic disease,cardiovascular system,urinary tract infections were excluded.All patients had not been previously treated with Angiotensin converting enzyme inhibitors(ACEI),angiotensin II type 1 receptor(AT1R)blocker(ARB),glucocorticosteroids,or immunosuppressive agents.Clinical indicators,including gender,age,height,weight,and blood pressure were collected when enrolled.Serum sample and urine sample were collected in all children before treatment.Serum and urine AGT levels were measured by human enzyme linked immunosorbent assay(ELISA)kits and adjusted by urinary creatinine.Serum concentrations of creatinine(SCr),blood urea nitrogen(BUN),urinary concentrations of protein(UP)and urinary concentrations of creatinine(UCr)were measured in laboratory of our hospital.Compare the differences of PAGT and UAGT levels in those three groups,and investigate the relationship between UAGT and all kinds of clinical parameters in HSPN patients.Comparisons among groups were done by one-way ANOVA and Scheffe test was applied for two independent sample comparisons.Pearson correlation analysis was used to determine the relationships between UAGT and clinical indices.P<0.05 was considered statistically significant.ResultsUAGT/UCr levels were significantly higher in HSPN(19.08±13.15 ug/g)compared with HSP children(6.97±3.51 ug/g)and control subjects(3.41±2.09 ug/g)(P<0.01).UAGT/UCr levels of healthy controls were lower than in HSP(P>0.05),the difference was not statistically.But serum angiotensinogen levels were no significant difference between these three groups(HSPN 27.388±10.697 ug/ml;HSP 27.067±17.331 ug/ml;control 31.059±14.945 ug/ml)(P>0.05 for all).Pearson correlation analysis showed that there was no significant correlation between UAGT/UCr and BUN(r=0.011,P=0.955)and serum angiotensinogen(r=-0.303,P=0.104).UAGT/UCr levels correlated positively with SCr(r=0.540,P=0.002)and urinary concentrations of protein/urinary concentration of creatinine(UP/UCr)(r=0.373,P=0.043),UAGT/UCr was correlated negatively with e GFR(r=-0.419,P=0.021).ConclusionsUAGT/UCr levels in HSPN patients was significantly increased and correlated positively with SCr and urinary concentrations of protein/urinary concentration of creatinine(UP/UCr),UAGT/UCr was correlated negatively with e GFR,and there was no significant correlation between UAGT/UCr and serum angiotensinogen.These data indicated that the intrarenal RAS activation maybe involve in the occurrence and development of renal injury in HSP children.Urinary angiotensinogen levels in the acute phase maybe used as a indicate biomarker of renal impairment in patients with HSP.We can judge severity of the disease and predict the progression and prognosis of renal damage in HSP by monitoring UAGT levels in the acute phase.Which may provides useful information for chosen the best treatment perscription for pediatric HSP patients.