Diffusion-weighted MR imaging of kidneys in patients with systemic lupus erythematosus: initial experience

To evaluate kidney perfusion and diffusion in patients with systemic lupus erythematosus (SLE) and define any correlation between laboratory features of renal involvement and apparent diffusion coefficients (ADCs). We studied 35 patients with SLE and 30 healthy volunteers. Ten of the patients were diagnosed as having lupus nephritis. Transverse diffusion-weighted multisection echo-planar magnetic resonance imaging was created with the following diffusion gradient b values: 0, 111, 222, 333, 444, 556, 667, 778, 889, and 1,000 s/mm². Statistical analyses to compare ADCs of kidneys between patients in the study and control groups were done with the independent sample t test. The Pearson correlation analysis was used to evaluate the relation between the renal function variables and the ADCs. There was statistically significant difference between the ADC_low values and the urine protein levels (P < 0.05) in the patients with SLE. Also, there was a significant correlation between the duration of nephritis and urine protein levels in the patients with SLE (P < 0.01). There was no statistically significant differences regarding ADCs, serum creatinine levels, and GFRs among patients with SLE and controls. Our patients had mild SLE and this might be the reason that no statistically significant differences were found between ADCs, and laboratory features of renal involvement among patients with SLE and controls. Larger series and more diffusion experience may be valuable for future studies.