Differential contribution of the factors determining long-term renal function after partial nephrectomy over time.

PURPOSE: To define how much of renal function was determined by the preserved renal parenchymal volume and the ischemic insult during partial nephrectomy (PN) long after surgery. METHODS: We analyzed the data of 530 consecutive patients who had undergone PN. For all patients, renal function was measured preoperatively and again at 3 postoperative months, then annually using 99mTc-diethylenetriaminepentaacetic acid renal scan. Perioperative variables potentially affecting the long-term ipsilateral glomerular filtration rate (GFR) and their time-varying contribution were assessed using a linear mixed model. RESULTS: The mean preoperative ipsilateral GFR was 42.9 ml/min, which decreased by 27.3% at 3 months but began to recover thereafter continuing until 4 years (Δ% GFR at 1, 2, 3, 4, and 5 years: 22.3%, 18.5%, 14.7%, 10.0%, and 9.6%, respectively). Parenchymal volume reduction and ischemic time were significantly associated with postoperative ipsilateral GFR throughout observation period unvarying with time. Diabetes and proteinuria were not significant determinants of ipsilateral function at 3 months but became significant at 5 years. In multivariate analysis regarding recovery slope, volume reduction (ß = -0.026, SE 0.006, P < 0.0001), preoperative ipsilateral GFR (ß = -0.021, SE 0.007, P = 0.0012), proteinuria (ß = -0.942, SE 0.372, P = 0.0116), and diabetes (ß = -0.396, SE 0.197, P = 0.0447) were independently significant. CONCLUSION: Ipsilateral renal function continued to improve until 5 years after PN. Parenchymal volume loss was the major determinant and its impact on long-term ipsilateral renal function remained constant while ischemic time affected early GFR reduction with its impact diminishing over time. Patient-related factors including diabetes and proteinuria gained significance over time and became independent determinants of recovery slope.

Renal Abnormalities Among Egyptian Children With Hemophilia A Using Renal Scintigraphy: Relation to Risk Factors and Disease Severity.

Many risk factors may contribute to renal disease in patients with hemophilia A. AIM: We aimed to evaluate functional and structural renal abnormalities among a group of Egyptian children with severe and moderate hemophilia A using technetium-99m diethylene triamine pentaacetic acid (99mTc-DTPA) and technetium-99 m dimercaptusuccinic acid (99mTc-DMSA) scan. We also aimed to determine the relation between these abnormalities and different risk factors and disease severity. PATIENTS AND METHODS: Forty male patients, 16 with severe and 24 with moderate hemophilia A, were enrolled in this study. Their mean age was 10.2 ± 4.3 years (range, 5-17 years). Full history taking, clinical examination, laboratory, and radionuclide investigations including serum creatinine, blood urea nitrogen (BUN), urine analysis, creatinine clearance, 24-hour urinary protein, 99mTc-DTPA scan, and 99mTc-DMSA scan were performed to all enrolled patients. RESULTS: Serum creatinine and BUN were normal in all patients, and corrected creatinine clearance was diminished in 2 patients. However, 99mTc-DTPA results yielded 19 (47.5%) patients with diminished glomerular filtration rate (GFR). Moreover, it showed that 14 (35%) had obstructive uropathy, 15 (37.5%) had obstructive nephropathy, while 11 (27.5%) patients showed normal scan. One patient had atrophy of 1 kidney on 99mTc-DMSA scan. Among our cohort, 5 (12.5%) patients were hypertensive. Microscopic hematuria was detected in 14 (35%) patients while 72.5% had proteinuria. We found an association between hematuria and hypertension with diminished GFR. CONCLUSION: Despite normal kidney functions (serum creatinine and BUN), we found a high rate of diminished GFR and obstructive uropathy and nephropathy as detected by 99mTc-DTPA scan among children with hemophilia A.

Factors affecting changes in the glomerular filtration rate after unilateral nephrectomy in living kidney donors and patients with renal disease.

PURPOSE: We evaluated the factors affecting changes in the postoperative glomerular filtration rate (GFR) after unilateral nephrectomy in living kidney donors and patients with renal disease. METHODS: We studied 141 subjects who underwent living donor nephrectomy for renal transplantation (n = 75) or unilateral nephrectomy for renal diseases (n = 66). The GFR of the individual kidney was determined by Tc-99m DTPA scintigraphy before and after nephrectomy. By performing multiple linear regression analysis, we evaluated the factors that are thought to affect changes in GFR, such as age, sex, body mass index (BMI), preoperative GFR, preoperative creatinine level, operated side, presence of diabetes mellitus (DM), presence of hypertension (HTN), and duration of follow-up. RESULTS: In both the donor nephrectomy and the disease nephrectomy groups, GFR increased significantly after nephrectomy (46.9 ± 8.4 to 58.1 ± 12.5 vs. 43.0 ± 9.6 to 48.6 ± 12.8 ml/min, p < 0.05). In the donor nephrectomy group, age was significantly associated with change in GFR (ß = -0.3, p < 0.005). In the disease nephrectomy group, HTN, preoperative creatinine level, and age were significantly associated with change in GFR (ß = -6.2, p < 0.005; ß = -10.9, p < 0.01; ß = -0.2, p < 0.01, respectively). This compensatory change in GFR was not significantly related to sex, duration of follow-up, or operated side in either group. CONCLUSIONS: The compensatory change in the GFR of the remaining kidney declined with increasing age in both living kidney donors and patients with renal disease.

Fractional Creatinine Clearance of the Donated Kidney As a Predictor of Graft Function after Living Donor Transplantation / 대한이식학회지

PURPOSE: An insufficient functioning nephron mass might fail to meet the metabolic demands of the recipient and lead to hyperfiltration. This hyperfiltration damage also increase allograft failure rates. During the preoperative evaluation of a potential kidney donor, it is important to estimate the renal function of donated kidney compared with the metabolic needs of the recipient. METHODS: The functional ratio of each kidney was measured using technetium-99m diethylenetriaminepentaacetic acid. The serum creatinine (Scr, mg/dL) and estimated creatinine clearance (Ccr, mL/min/1.73m2) using the Cockcroft-Gault formula were measured and calculated in 82 donors. We excluded recipients who had an episode of rejection, and followed all recipients for more than 12 months posttransplantation. RESULTS: The average functional proportion of the donated kidney was 50.5%+/-4.7% of the total Ccr 83.4+/-18.3 of donors. The Scr of recipients at 1,3,6 and 9months posttransplantation were significantly (P<.05) correlated with the fractional Ccr of thedonated kidney; however Scr at 1 year was not correlated (P=.307). Furth-ermore the Ccr of the recipient at 1, 3, and 6months post transplantation were significantly (P<.05) correlated with fractional Ccr ofthe donated kidney; however the Ccr at 9months and 1 year were not correlated (P=.094 and.141, respectively). CONCLUSION: The Scr and Ccr of recipients within 6 months after transplantation may depend on the functional mass of the donated kidney, which should be estimated prior to kidney donation and compared with the metabolic demands of the potential recipient.

The Clinical Significance of Routine Screening for the Renal Functional Asymmetry in Potential Live Kidney Donor

PURPOSE: An insufficiently functioning nephron might fail to meet the metabolic demands of a kidney donor, as well as the recipient, and may lead to hyperfiltration. An extreme asymmetry of the functional capacity of donor's bilateral kidneys might result in insufficiency to the recipient or donor. METHODS: Since February 1996, 99mTc-DTPA renal scintigraphy has been routinely included in the evaluation of renal functional asymmetry of a donor. The functional ratio of each kidney, using 99mTc-DTPA, as well as the serum creatinine (Scr) and creatinine clearance (Ccr), were measured and calculated using the 24-hour urine from a hundred donors. RESULTS: A hundred kidney donors were analyzed, including 62 male and 38 female donors. In the healthy donors, the average functional ratios of the left vs. the right kidneys were 52.5 vs. 47.5%. Seventy-three donors donated their left kidney and 27 their right. The Scr of the donors increased from 0.9+/-0.2 to 1.3+/-0.3 mg/dl after the nephrectomy. Both the Ccr in the 24 hour urine and the Ccr obtained using the Cockcroft and Gault formula of the remnant kidney after kidney donation increased from 54.5+/-11.4 to 68.0+/-14.3 ml/min/1.73 m2, and from 40.8+/-9.3 to 53.6+/-11.6 ml/ min/1.73 m2, respectively. CONCLUSION: Attention should be paid to the functional asymmetry of the kidney when choosing a kidney for donation. To protect the remnant kidney of a donor from hyperfiltration damage after donation, it is important to leave an adequate functioning nephron mass to meet the metabolic demands of the donor.

Comparison of DMSA scan and DTPA scan for evaluation of relative renal function in pediatric hydronephrosis / 대한비뇨기과학회지

The previous reports have indicated that both the DMSA scan and the DTPA scan were significantly related with the relative renal function ( RRF) and there was a close relationship between the DMSA scan and the DTPA scan in the evaluation of the RRF We reviewed our experience with 24 cases, in which the DMSA scan and the DTPA scan were performed within 2 weeks from January 1987 to April 1991. The DMSA scan was more reliable than the DTPA scan and the difference of the RRF between right and left side by the DMSA scan was more apparent than that by the DTPA scan. However, in infants, both scans showed the reversed results. Our study suggests that DMSA scan is more reliable than the DTPA scan in the evaluation of the RRF, but both renal scans are inappropriate in infants, especially under the age of 1 months.