The Clinical Value Of Microalbuminuria In Early Renal Injury In Critically Ill Patients

[Objective]Dynamically monitoring the variation of urinary micro-protein level for critically ill patients to explore the possibility of acting as an indicator for early kidney damage and provide laboratory evidence for early recognition, diagnosis, evolution and prognosis of the acute kidney injury.[Methods]Choosing30patients hospitalized in the ICU and EICU of Dongzhimen hospital affiliated to Beijing University of Chinese Medicine for more than a week from August,2013to January,2014as experimental subject. All these patients’urine samples had been deposited on the first, the third and the7th days after the hospitalization, taking enzyme-linked immunoassay method to monitor the level and variation of microalbumin, α1-microglobulin, β2-microgloulin, transferrinuria, retinol-binding protein in the urine with the first week in ICU.And respectively compared with the serum creatinine, glomerular filtration rate, urine protein in the same period. Meanwhile, data of the APACHE Ⅱ score, application of mechanical ventilation, mortality in28days was recorded. All patients were divided into three groups. The first group:13patients with high blood pressure, diabetes history as the experimental group,17patients with no high blood pressure or diabetes made up the control group, urinary micro-protein level of the two groups was comparatively analysed. The second group:9patients diagnosed with acute kidney injury after residing in ICU formed the experimental group, and the other21patients made up the control group. Uurinary micro-protein level of the two groups was comparatively analysed. The third group:a total of7cases of the experimental subjects died within28days, and23cases improved, comparing urinary micro-protein level of the two groups. Normal range and positive results in the hospital experimental subjects resided. Urine protein is negative in routine urine test, and the normal range value of serum creatinine is40-130umol/L, urine microalbumin<30mg/L,β2-MG<0.22mg/L, RBP<0.7mg/L, TRU<2.24mg/L.The abnormal level of urinary micro-protein associating with any other indicator with value above the normal level made the positive judgment.[Results]1. The positive rate of MA, β2-MG,α1-MG, RBP, TRU is high among the critically ill patients resided in ICU, with a rate of86.67%,60%,83.33%,83.33%,40%respectively in the first day of hospitalization. The positive rate of RBP is relatively low when monitoring RBP only, while the rate is93.33%when combined analysis was tooken. At the same time, the positive rate of serum creatinine, urine protein and GFR is30%,56.67%,33.33%respectively.2. Urinary micro-protein of experimental group (hypertensive or diabetics) and control group (non-hypertensive or diabetics) was compared. The difference in TRU on days1and3was statistically significant (P<0.05); differences in MA and β2-MG on day7were statistically significant (P<0.05)3. The weeklong micro-protein of AKI and non-AKI patients was compared. The differences in MA, β2-MG,α1-MG and TRU on the first week were statistically significant (P <0.05); In AKI patients, weeklong MA, β2-MG and α1-MG showed an increasing trend. In non-AKI patients, weeklong MA, β2-MG, α1-MG and TRU showed a decreasing trend.4. Weeklong urine protein of deceased patients and those whose conditions improved was compared. The difference in weeklong TRU was statistically insignificant (P<0.05); In deceased patients, weeklong MA, β2-MG, α1-MG and TRU showed an increasing trend. In patients who improved, weeklong MA, β2-MG, α1-MG showed a decreasing trend.5.The mortality rate of patients with AKI is55.6%, compared with control group.The length of stay are significantly different (P<0.05).About the age, gender, and the application of mechanical ventilation, there is no statistical difference between the two groups.[Conclusion]1. Dynamically monitoring the variation of MA, β2-MG, α1-MG, TRU level can act as the indicators of early kidney damage for patients of AKI and critically ill patients, and it is more sensitive compared with SCR, GFR, urinary protein. And the sensitivity is even more higher when dynamically monitoring them all. Monitoring the MA, α1-MG, TRU singly can provide more sensitivities to predict and evaluate the condition of patients comparing with monitoring the other two indicators respectively.2. Dynamically monitoring the variation trend of MA, β2-MG, α1-MG level is helpful in early recognition, juging the degree of kidney damage, and evaluating the prognosis of the patients.3. The condition of patients in ICU is complicated and critical, and most of the ICU patients is elderly people, with more basic diseases (hypertension, diabetes, etc). The kidney function has been damaged to different extent before residing in ICU for most of them, the incidence rate of kidney damage is extremely high, dynamic monitoring the microalbuminuria is meaningful for the early kidney damage. The study has showed that the incidence rate and mortality of AKI are very high, thus early recognition, diagnosing and taking actions to intervene the development of AKI has a great significance to improve the prognosis and decrease the mortality.