Image-directed color Doppler ultrasound evaluation of the single kidney after unilateral nephrectomy in adults

Deterioration in the renal function and risk of microalbuminuria after radical, simple and donor nephrectomy: A long-term outcome

Objectives:

Evaluation of deterioration in renal function and risk of micro albuminuria after radical, simple and donor nephrectomy.

Materials and Methods:

A total of 594 patients underwent nephrectomy (159 radical, 318 simple and 117 donors) from February 2009 to December 2012 in our institute. First 300 eligible patients were divided in 3 groups, each having equalled number of patients. Group 1 was consisted of patients who underwent radical, group 2 had simple and group 3 had donor nephrectomy. These patients were followed up to February 2015. Follow up of all the patients were done at first month following the surgery and then in every six months subsequently. The follow up included the measurement of serum creatinine and urinary micro albumin in a spot urine sample. CKD-EPI equation was used for calculation of e GFR.

Results:

At the end of our study, 35 patients (41.6%) in group 1 and 8 patients (8.69%) in group 2 developed CKD stage 3. During the follow-up period, 41% patients in group 1, 13% in group 2 and 4% in group 3 developed MA.

Conclusion:

Nephron-sparing surgery should be the standard treatment of renal tumors, wherever possible. There should be a regular follow up of the patients after radical, simple and donor nephrectomy because of risk of CKD. Early consultation with nephrologists should be done by the patients who are suffering from MA after nephrectomy.

Predictive preoperative factors for renal insufficiency in patients followed for more than 5 years after radical nephrectomy

Purpose

We assessed the predictive factors for renal insufficiency in patients followed for more than 5 years after radical nephrectomy.

Materials and Methods

Age, gender, history of diabetes, history of hypertension, body mass index, preoperative estimated glomerular filtration rate (eGFR), serum uric acid, urine albumin, normal renal parenchymal volume, tumor size, and ratio of normal parenchymal volume of the removed kidney to that of the remaining kidney were evaluated retrospectively in 89 patients who underwent radical nephrectomy from January 2001 to December 2005. Patients were included whose renal parenchymal volume was measurable by use of perioperative imaging (computed tomography or magnetic resonance imaging), whose preoperative eGFR was greater than 60 mL/min/1.73 m², and who were followed for more than 5 years. To measure renal parenchymal volume from imaging, we integrated the extent of the normal renal parenchyma from axial slides of images.

Results

In univariate and multivariate binary regression analysis, the parenchymal volume of the remnant kidney (p=0.001), a history of diabetes (p=0.035), and preoperative eGFR (p=0.011) were independent factors for renal insufficiency. By use of a receiver operating characteristic curve, a volume of 170 mL was determined to be an appropriate cutoff value, with sensitivity of 58.7% and specificity of 74.4% for the parenchymal volume of the remnant kidney for predicting eGFR less than 60 mL/min/1.73 m² (area under the curve, 0.678). The parenchymal volume of the remnant kidney was also an independent factor for the downgrading of the chronic kidney disease category in the multivariate linear regression analysis (p=0.021).

Conclusions

Preoperative eGFR, a history of diabetes, and the radiologic volume of the remaining kidney parenchyma could be useful factors for predicting postoperative renal function. Patients with parenchymal volumes of less than 170 mL have a higher risk of postoperative renal insufficiency, which should be considered carefully when choosing a treatment modality.

The value of quantitative 99M technetium dimercaptosuccinic acid renal scintigraphy for predicting postoperative renal insufficiency in patients undergoing nephrectomy

PURPOSE

Radical nephrectomy is a routine urological practice. However, little is known about the use of dimercapto-succinic acid (DMSA) scan to evaluate compensatory changes after surgery and its ability to identify patient at risk for postoperative chronic renal failure or insufficiency. We predicted remaining kidney function using DMSA scan and serum creatinine.

MATERIALS AND METHODS

A total of 42 patients were enrolled in the study. All underwent DMSA scan before surgery and in 38 DMSA scan was done after unilateral nephrectomy. Serum creatinine was determined before and 1 year after surgery. The Student t test was used to determine statistical significance. Spearman rank core analysis was used to evaluate the association of calculated creatinine clearance time after surgery and renal absolute uptake before surgery. We performed 1-way ANOVA comparison of the means to determine the influence of age distribution on kidney hypertrophy and the increase in kidney uptake.

RESULTS

Average patient age was 61.5 years. Baseline mean creatinine clearance time was 71.5 ml. per minute, which decreased to 58.6 ml. per minute after nephrectomy (p <0.0001). Before surgery DMSA scan of the remaining kidney demonstrated an absolute uptake of 4.2% higher than that in the resected kidney (13.5% versus 9.35%, p = 0.0008). After nephrectomy the remaining kidney had an average increase of 3.9% of mean absolute uptake (17.7% versus 13.8%, p = 0.0001). Spearman rank core analysis demonstrated an association of higher preoperative absolute uptake in the remaining kidney with postoperatively high creatinine clearance time (r = 0.458, p = 0.003). Furthermore, 75% of patients with postoperative creatinine clearance time less than 40 ml. per minute presented with a preoperative absolute uptake of lower than 11% in the remaining kidney. In contrast, 75% of those with a postoperative creatinine clearance time of higher than 40 ml. per minute had a preoperative absolute uptake of higher than 11%.

CONCLUSIONS

A preoperative absolute uptake of lower than 11% in the remaining kidney was a significant risk factor for postoperative chronic renal insufficiency.