Scintigraphic Evaluation of Renal Function in Patients with Hepatitis B Virus Infection

Aim: Chronic hepatitis B virus (HBV) infection can induce nephropathy and major HBV antigens (HBcAg, HBeAg, HBsAg) and immune complexes responsible for its pathogenesis. The purpose of our study was to assess the renal function of patients with HBV infection by means of technetium diethylenetriamine pentaacetic acid (Tc99m DTPA) scintigraphy, in order to detect any early renal dysfunction, which might be related to nephropathy associated with HBV infection. Methods: Nineteen patients (10 male and 9 female with a mean age of 37.11±11.34 years, age range 25−62 years) with the diagnosis of HBV infections, and 16 healthy controls (8 male and 8 female with a mean age of 33.50±11.56 years, age range 24-55 years) were enrolled into the study. All subjects had no history of renal disease and treatment of HBV infection including interferon-alfa, pegylated interferon-alfa, lamivudine and adefovir. Blood urea nitrogen (BUN), urea and creatinine were analyzed. The renal perfusion, concentration and excretion were evaluated by Tc99m DTPA scintigraphy. The time to peak (TTP), peak activity (counts/second) (PA), clearance half time (T1/2) and percent contribution of each kidney to total function (differential function) were calculated. The glomerular filtration rate (GFR) was determined simultaneously by 3 methods; gamma camera uptake method (Gates, GFR), predicted creatinine clearance method (Cockcroft-Gault, CG-GFR), and Modification of Diet in Renal Disease (MDRD). The variables were compared between groups. Results: The mean values of patients’ parameters were as follows; right TTP:5.73±3.14 min, left TTP:5.52±2.09 min, right PA:884.78±214.85 cts/sec, left PA:889.52±252.68 cts/sec and right T1/2:17.84±6.89 min, left T1/2:14.51±8.59 min. Differential functions were 50.27±3.39% on the right side and 49.72±3.39% on the left side. In study group, Gates GFR value was 125.63±25.84 ml/min, CG-GFR:124.05±24.32 ml/min, MDRDGFR:113.15±24.70 ml/min/1.73 m, BUN:14.57±5.05 mg/dl, urea: 27.37±10.24 mg/dl, and creatinine:0.73±0.18 mg/dl. The mean values of control group were as follows; right TTP:4.05±1.87 min, left TTP:2.93±1.14 min, right PA:819.25±260.48 cts/sec, left PA:796.75±176.94 cts/sec, and right T1/2:12.25±3.19 min, left T1/2:12.25±5.49 min. In control group, Gates GFR value was 109.75±39.03 ml/min, CG-GFR:104.62±39.67 ml/min, MDRD-GFR:89.68±34.15 ml/min/1.73 m, BUN:11.37±4.47 mg/dl, urea:24.75±5.54 mg/dl, and creatinine:0.78±0.17 mg/dl. There were a statistical difference between patients and controls groups at right TTP value and left TTP value (p<0.020 and p< 0.000, respectively). Glomerular filtration rate and clearance half time increased in patients with HBV as compared with control group, but there were no statistical difference. However, 18 patients had stasis in different localization and degree. In three patients, stasis was spontaneously drained, and washout of radioactivity was obtained by intravenous diuretic application in the other patients with stasis. Conclusion: We concluded that Tc99m DTPA scintigraphy is a non-invasive and practical method to evaluate renal functions quantitatively or semi-quantitatively in patients with nephropathy possibly secondary to HBV infection. But further studies in large series are needed.