OBJECTIVETo investigate the clinical significance of dynamic changes of blood urea nitrogen (BUN), serum creatinine (Cr), serum cystatin (Cys C) and urinary protein on renal injury with paraquat poisoning.

METHODSAccording to the clinical manifestation and curative effect, the clinical information was analyzed retrospectively in 35 cases of acute paraquat poisoning, survival after eight weeks as the standard. Poisoning patients were taken a fasting blood 5 ml and the middle of urinary on the 1st day, 3rd day, 7th day, 14th day, 21st day and 8 weeks after the poisoning. Then the levels of serum BUN, Cr, Cys C and urinary protein were detected by automatic biochemistry analyzer. 30 cases healthy subjects were randomly selected as normal control group, and discharged kidney disease and other diseases of urinary system history. The same laboratory subjects have been done.

RESULTSThe level of serum Bun, Cr, Cys C of survival group increased significantly compared with control group within 21 days (P < 0.05). The level of serum BUN, Cr Cys C decreased on the 14th day. The decreased level of serum Cys C was lower than that of serum BUN and Cr. The renal function of 29 cases among 35 cases survival patients recovered on 21st day. The renal function of 31 cases among 35 cases survival patients recovered 8 weeks late. The positive rate of urinary protein of survival patients was high in the early intoxication (76.9%).

CONCLUSIONSerum Cys C is sensitive indicator to reveal the kidney injury on paraquat poisoning patients and have higher value of clinical applications in the diagnosis of the kidney injury of paraquat poisoning, which sensitivity is higher than serum BUN and Cr. The kidney injury caused by paraquat poisoning is reversible.