Abstract: Objective To investigate the sensitive indexes which can diagnose early renal damage in SLE.Methods We used radioisotope renogram with ^99m Tc-DTPA as a tracer,to examine the glomerular filtration rate(GFR) and assessed renogram quantitatively in 58 patients.Results The results showed that the GFR calculated by the Gates method correlated well with creatinine clearance rate,but had no correlation with the duration of the disease.Only 50% of the patients showed abnormal renogram.There were abnormal half clearance time and 15-minute residual ratio in 93.1% and 85.3% of the patients respectively after quantitative renogramanalysis.However,there were only 67.3% of patients had renal damage clinically,the positive rates of half clearance time and 15-minute residual ratio were much higher than those found by clinical examination.Even when GFR was normal,there were 88.5% of the patients showed prolonged half clearance time.We also found that half clearance time and 15-minute residual ratio were much more sensitive than blood urea nitrogen or/and creatinine clearance rate determination.Conclusion The results suggest that quantitative renogramanalysis may increase the sensitivity in assessing the renal damage.

Key words: Lupus erythematosus, systemic, Renogram