The Study Of Kidney Injury Molecule-1 In Urine And The Of Correlation Between Kidney Injury Molecule-1 And Renal Injury After Neonatal Asphyxia

Objective: Neonatal asphyxia is a major cause of neonatal death and disability. The main reason for this is multiple organ injury caused by asphyxia and anoxia. It was reported by Perlman et al that, about 70% of newborns with asphyxia combined different levels of organ injury, in which the incidence of renal injury in 57% [1]. In recent years, many studies are on hypoxic-ischemic renal injury. Proximal renal tubular cells are particularly sensitive to hypoxia, so the hypoxic-ischemic renal injury occurred mainly in proximal tubular cells. Kidney injury molecule -1 (Kim-1) which is found in recent years is a new kind of transmembrane glycoprotein. There are traces of Kim-1 in the normal liver, kidney and spleen, meanwhile, it is markedly increased in ischemic injury and renal toxicity dedifferentiation of the renal proximal tubule epithelial cells. By detecting urinary kidney injury molecule -1 (Kim-1) levels in asphyxial and HIE newborns and comparing with blood urea nitrogen (BUN), creatinine, urinaryβ2-microg- lobulin (β2-MG) and endothelin-1 (ET-1) ,the study will discuss the significance of Kim-1 in newborns with asphyxia at the level of urine and its relationship with the degree of asphyxia and the degree of renal injury in the relationship between the early detection of neonatal asphyxia renal injury to determine the location and extent of damage to assess the prognosis of renal injury basisMethods:Choose perinatal asphyxia Branch (intrauterine / postnatal) 60 cases of newborns in Fourth Hospital of Hebei Medical University and Hebei Children's Hospital (38 cases were mild asphyxia, severe asphyxia in 22 cases).Asphyxia group are divided into groups with normal renal function (15 cases) and renal injury group (45 cases) by urine, azotemia and creatinine levels. Besides, there is a normal control group (no history of hypoxia and severe infection, neonatal birth trauma)-20 cases. Detection of urinary Kim-1,β2-MG, ET-1 level was made in neonatal day 1 (D1), the first four days (D4) separately by enzyme-linked immunosorbent assay (ELISA) andradio- immunoassay.Asphyxia group dedicated peripheral venous blood at the same time by means of automatic biochemical analyzer which detected BUN and Cr. It was recorded that the newborns selected neonatal gestational age, age in days, weight, and urine volume. Combined with comparative analysis of relevant clinical data, a statistical treatment was conducted.Results: 1 The change of asphyxia neonatal urinary Kim-1,β2-MG, ET-1 levels 1.1 Normal control group and neonatal asphyxia group urine Kim-1,β2-MG, ET-1 level changes: in the 1st day(D1) and the 4th day(D4), asphyxia group of urine Kim-1,β2-MG, ET-1 level was significantly high than the same-day-old normal control group. There is a statistically significant difference (P <0.01); in the fourth day, urine Kim-1,β2-MG, ET-1 levels of asphyxia group were decreased than the first day. It was proved that there was a significant by t-test (P<0.01).1.2 Different degree of neonatal asphyxia urine Kim-1,β2-MG, ET-1 level changes: On postnatal day 1 and on postnatal day 4, normal control group, mild asphyxia group and severe asphyxia group urine Kim-1,β2-MG, ET-1 level increasing order, variance analysis showed that between the three groups, There are significance differences in statistics (P<0.01); multiple comparison showed the mild asphyxia group and the normal control group, severe asphyxia group and the normal control group, severe asphyxia group and the mild asphyxia group, the differences were significant (P<0.01). On postnatal day 4, mild asphyxia group and the severe asphyxia group urine Kim-1,β2-MG, ET-1 levels decreased than on postnatal day 1. There were significance differences by T test (P<0.01),1.3 Comparison of abnormalities on difference from degree of suffocation urine Kim-1,β2-MG, ET-1: For same day- old normal control group with x +1.96 s as the upper limit of normal, compared urine Kim-1,β2-MG and ET -1's incidence of the abnormal one. Severe asphyxia group was higher than that target abnormal with mild asphyxia- day-old group, significant differences (P<0.01); the same day within the same group of urine Kim-1 was significantly higher than the incidence of abnormal urineβ2-MG,ET-1,significant differences (P<0.01). In the same group of different days, urine Kim-1,β2-MG, ET-1 incidence of abnormal on 1st day were higher than on the fourth day, significant differences (P<0.01).1.4 Renal injury group urine Kim-1,β2-MG, ET-1 levelsOn the 1st day and the fourth day: the normal control group, normal renal function and renal injury group urine Kim-1,β2-MG,ET-1 increased systematically, variance analysis showed that duing the three groups there was statistically significant difference (P<0.01); further multiple comparison among normal renal function group and normal control group, renal injury group and normal control group, renal injury group and normal renal function group, the differences were significant (P<0.01). On the fourth day normal renal function and renal injury group urine Kim-1,β2-MG, ET-1 levels were decreased comparing to day 1, t-test were significantly different (P<0.01)2 Urine Kim-1 andβ2-MG, ET-1 of the correlation analysis On the 1st day and the 4th day, urine Kim-1 andβ2-MG, ET-1 were positively correlated (P<0.01).Conclusion:1 Kim-1 level was significantly increased in renal injury in neonatal asphyxia urine, the changes of which is coincide with the degree of renal injury and the degree of asphyxia consistent, suggesting that Kim-1 was involved in renal injury after asphyxia in the pathophysiological process.2 asphyxia neonatal founded renal function injury in early time, evev though wound be recover on postnatal day 4, but not normal levels. Its change trend is in accord with urine beta 2 - MG which reflects the tubular damage, but the abnormal rate significantly higher thanβ2-MG, the urine Kim-1 levels can early reflect the extent of the renal damage especially the damage of renal tubules.3 after renal injury in newborns with asphyxia, while the existence of tubular and glomerular dysfunction and renal tubular damage in the main. Molecular detection of renal injury -1 (Kim-1) has probably become the early detection of kidney injury, renal tubular injury to determine the sensitivity of biological markers. The detection of urine Kim-1 isn't affected by the other urine physicochemical property, while avoiding the obstruction of the other existing urine indicators.