Early effects of percutaneous nephrolithotomy on glomerular filtration rate and determining the potential risk factors responsible for acute postoperative renal function impairment

In this study, the early effects of percutaneous nephrolithotomy [PCNL] on glomerular filtration rate [GFR] was assessed in different postoperative times and likewise, we determined the correlation of different variables with significant postoperative GFR drop after PCNL. Patient records of 486 cases that had undergone PCNL from January 2010 to October 2011 were reviewed retrospectively. GFR in six hours, one, two and three days after PCNL and in the discharge day were calculated and then compared with preoperative level. Correlation between different variables [Perioperative hemorrhage, co-morbidities, previous stone surgery, renal anomaly, number of access, stone burden and location] and risk of acute postoperative renal function impairment [GFR drop greater than 25%] were assessed. Mean preoperative GFR was 87.85 +/- 29.41ml/min/1.73m[2] which decreased to 86.18 +/- 28.77, 78.45 +/- 28.74, 78.79 +/- 26.94, 84.24 +/- 29.71 and 86.18 +/- 28.77 in 6, 24, 48 and 72 hours after surgery and discharge day post PCNL, respectively. GFR significantly decreased in one and two days after surgery [p value<0.0001 and p value <0.05] but returned to near preoperative values in 3th post PCNL day. Among different variables, only perioperative bleeding [Cut-off point for serum hemoglobin drop was 2.8 mg/dL] was concomitant with significant postoperative renal function impairment. Our findings revealed that co-morbidities, large or multiple stones, multiple punctures and previous history of stone surgery have no significant impact on surgical outcomes. Postoperative GFR returned to near preoperative values in a few days after operation. Avoidance of significant perioperative bleeding is an important point to prevent post PCNL renal insufficiency

possibility of access to the kidneys from posterior axillary line in supine position for percutaneous nephrolithotomy

To evaluate the possibility of access to the kidneys from posterior axillary line [PAL] in supine position for percutaneous nephrolithotomy. 102 consecutive patients who were candidated for abdominal CT scan, enrolled in this study. In cases of impossible access, the point on the posterior surface of body which permitted safe access was determined and the percent of movement toward body midline [relative to PAL] was calculated [M.PER]. Percutaneous access was simulated from upper and middle calyces of the kidney in 13% and 75% of cases, respectively. Access to the lower region was possible in 90% of right and 79% of left lower calyces, respectively [p=0.03]. In cases with impossible access from PAL, the M.PER for a safe access was 46-47% for upper region and 34-38% for middle and lower calyces of the kidney [P = 0.0001]. Access to upper calyces from PAL was limited in some cases regarding to the presence of solid organs. Presence of colon made access impossible in the lower right and left calyces in about 10% and 20% of cases, respectively. In upper region, more deviation toward midline was necessary to establish a safe access compared with middle and lower calyces

Neurologic Complications in Percutaneous Nephrolithotomy

PURPOSE: Percutaneous nephrolithotomy (PCNL) has been the preferred procedure for the removal of large renal stones in Iran since 1990. Recently, we encountered a series of devastating neurologic complications during PCNL, including paraplegia and hemiplegia. There are several reports of neurologic complications following PCNL owing to paradoxical air emboli, but there are no reports of paraplegia following PCNL. MATERIALS AND METHODS: We retrospectively reviewed the medical records of patients who had undergone PCNL in 13 different endourologic centers and retrieved data related to neurologic complications after PCNL, including coma, paraplegia, hemiplegia, and quadriplegia. RESULTS: The total number of PCNL procedures in these 13 centers was 30,666. Among these procedures, 11 cases were complicated by neurologic events, and four of these cases experienced paraplegia. All events happened with the patient in the prone position with the use of general anesthesia and in the presence of air injection. There were no reports of neurologic complications in PCNL procedures performed with the patient under general anesthesia and in the prone position and with contrast injection. CONCLUSIONS: It can be assumed that using room air to opacify the collecting system played a major role in the occurrence of these complications. Likewise, the prone position and general anesthesia may predispose to these events in the presence of air injection.

Effects of stem cells and granulocyte colony stimulating factor in reperfusion injury

Bone marrow-derived stem cells have a potential capacity to differentiate and accelerate recovery in injured sites of body. Also, factors like granulocyte colony stimulating factor [GCSF] can promote their mobilization to the injured sites. We aimed to investigate the role of GCSF as an alternative therapeutic option instead of mesenchymal stem cells [MSCs] in reperfusion injury. Twenty-nine rats with induced reperfusion injury were divided into 3 groups to receive MSC, GCSF, or nothing [control]. Kidney function was assessed by blood urea nitrogen and serum creatinine levels. Histological grading was performed to evaluate the extent of tubular injury and the rate of recovery. All the rats reached recovery after 14 days. Rats in the MSC group reached early functional and histological recovery compared to the controls on the 7th day of the study [P = .01 and P = .02, respectively]. Compared to the control group, the GCSF group showed a more significant histological recovery on the 7th day [P = .04], but kidney function was ameliorated on the 14th day [P = .04]. Both the GCSF and control groups had a significant number of CD34+ cells, which were detected by flow cytometry on the 7th day after reperfusion injury. We found therapeutic effects following administration of both MSC and GCSF which was more evident with MSC in the setting of reperfusion injury. More investigation is required to find optimal time, dose, and route of administration as well as other possible contributing factors

Early continence after open and laparoscopic radical prostatectomy with sutureless vesicourethral alignment an alternative technique, 8 years experience

We reviewed urinary outcomes after sutureless vesicourethral alignment in open radical prostatectomy [ORP] and laparoscopic radical prostatectomy [LRP]. Charts of 324 patients who underwent sutureless ORP [n = 188] and LRP [n = 136] were reviewed. After prostatectomy, a 22-to 24-F silicon Foley catheter was passed into the bladder via the preserved bladder neck. The Foley balloon was filled, and mild traction was applied to appose the bladder neck to the urethral stump. The Foley catheter was fixed to the patient's leg. No cystostomy was placed. The follow-up period ranged from 12 to 60 months. The mean operative time was 65 minutes in ORP and 260 minutes in LRP. Blood transfusion was significantly less frequent with LRP [9.6% versus l9.7%, P = .02]. The mean postoperative catheterization durations were 12 days in ORP and 13 days in LRP. Complete continence was achieve in 293 patients [90.4%] after 3 months of follow-up [88.9% in LRP and 91.5% in ORP, P = .78]. The continence rate improved to 96.3% in LRP and 95.2% in ORP at 1 year [P = .52]. Bladder neck stricture rate was 13.6% [12.8% in ORP versus 14.7% in LRP, P = .87]. Sutureless vesicourethral alignment during ORP and LRP is a promising approach with minimum urinary extravasation, a high rate of continence, and an acceptable rate of stricture. This technique could be considered as an alternative in anatomically demanding situations

Correlation between size of renal cell carcinoma and its grade, stage, and histological subtype

The aim of this study was to determine the correlation between histological subtype, size, grade, and stage of the kidney tumors and to investigate whether a correlation exists between the size of the kidney tumor and its behavior. Between 1996 and 2004, we had 212 patients with radical or partial nephrectomy due to a kidney tumor at Shaheed Labbafmejad Medical Center. Their pathologic blocks were re-evaluated with consideration of their tumor size and pathologic features. Of 212 pathologic blocks, 17 [8%] were benign and 195 [92%] were malignant masses including 179 renal cell carcinoma [RCC] tumors. Malignant tumors were slightly greater compared with the benign ones [P = .10]. There was no significant relation between the size of tumor and the histological subtype. Significant relations between the size of the kidney tumor and the nuclear grade [P = .007], clinical symptoms [P = .02], and extracapsular extension [P < .001] were observed. In smaller RCC tumors [< 4 cm], extracapsular extension [stages T3 and T4] was rare [1 in 29]. However, smaller RCC tumors were not significantly different from those larger than 4 cm regarding the nuclear grade, symptoms, and histological subtypes. Tumor size is not an independent predictor for the histological subtype of the tumors; however, larger malignant tumors may have higher grades, higher stages, and clinical symptoms

established rat model of inducing reversible acute tubular necrosis

Acute tubular necrosis [ATN] is a challenging problem that still requires to be studied in animal models. Our aim was to prepare an established experimental model of inducing reversible ATN in rats by determining the optimum duration of ischemia induction to the kidney. Twenty-four hour after nephrectomy of the right kidney and clamping the pedicle of the left kidney for durations ranging from 10 to 55 minutes, the kidney function and the histologic changes were evaluated. Accordingly, the optimum duration of clamping was determined and in the next step, it was considered for induction of reversible ATN in another group of rats. This group was followed up for 14 days and the pathologic course and function of the kidney were observed. Reversible ATN developed by 47-minute clamping of the renal pedicle. Blood urea nitrogen and serum creatinine levels were elevated up to threefold within 24 hours after the induction of ischemia and they decreased to their reference ranges after 12 and 6 days, respectively. In the histologic study of the kidneys, the least extend of injury was noted by the 14th day following the ATN induction. Even on the 14th day of the follow-up, some signs of ATN remained indicating that the tissue regeneration was not complete yet. To integrate the experimental models of ATN, a rat model with 47-minute clamping of the renal pedicle for induction of ischemia seems appropriate. The resultant ATN remains for a long duration, while kidney function is alleviated

En Bloc Kidney Transplantation from Pediatric Cadaveric Donors to Adult Recipients

The shortage of cadaveric donors for kidney transplantation has led to the expansion of the criteria used for donor selection, such as the use of pediatric cadaveric donors. In this study we reviewed our results of en bloc kidney transplantation of pediatric cadaveric donors to adults. From May 2001 to May 2005, 245 cadaveric kidney transplants have been performed in our hospitals. Seven of these were en bloc kidney transplantations in adult recipients from marginal pediatric donors [age < 5 years, donor weight < 15 kg, high creatinine clearance, or kidney length < 8 cm]. We reviewed their records. Follow-up [range, 3 to 24 months] included ultrasonography, dimercaptosuccinic acid renal scintigraphy, and magnetic resonance imaging. Serum levels of creatinine ranged between 0.8 m/dL to 1.9 mg/dL during the follow-up period. One patient died of myocardial infarction 3 months postoperatively. One-year graft and patient survivals were both 85.7%. Complications included acute tubular necrosis in 1 patient [managed by conservative therapy and dialysis for 2 weeks], renal vein thrombosis in 1 [treated by anticoagulation], and subcutaneous hematoma in 1. There were no urologic complications. Median size of the grafts was 7.2 cm preoperatively that reached 9.6 cm, 3 months postoperatively [P =.018]. Twelve months following operation, the median size of the grafts reached 11 cm [P =.045]. En bloc pediatric kidney transplantation is a safe and suitable alternative for adult recipients. One-year graft and patient survivals are acceptable and complication rate is low

Prediction of prostatic involvement by transitional cell carcinoma of the bladder using pathologic characteristics of the bladder tumor

The aim of this prospective study is to determine the relationship between the pathologic characteristics of the transitional cell carcinoma [TCC] of the bladder and prostatic involvement. Sixty men with bladder TCC underwent standard radical cystoprostatectomy and were enrolled in this study. Vascular and perineural invasion, maximum diameter of the tumor, presence of carcinoma in situ, distance between the tumor and the bladder neck, and grade and local stage of the tumor were recorded and their relation with prostatic involvement was studied. In addition, hydronephrosis and age of the patients were included in the analysis. The mean age of the patients was 63.9 +/- 11.1 years. Of 60 men included in this study, 15 patients were found to have prostatic involvement with TCC [25%]. Univariate statistical analyses showed that vascular invasion and the distance between the tumor and the bladder neck were significantly related to the prostatic involvement [P = .007; P < .001]. But, in the logistic regression, only the distance between the tumor and the bladder neck was significantly related to the prostatic involvement [P = .001]. This study suggests that the probability of prostatic involvement in patients with bladder TCC tumors near the bladder neck is high. Prostate-sparing or capsule-sparing cystectomy should be avoided in such patients

Percutaneous nephrolithotomy with and without retrograde pyelography: Preliminary results of a randomized controlled trial

Since the introduction of percutaneous nephrolithotomy [PNL], many modifications to entering the pyelocalyceal system have been made. One alternative is to insert a needle pointed to an opaque stone as a landmark. The aim of this study was to compare the outcomes of managing kidney calculi by PNL with and without retrograde pyelography. In this randomized controlled trial, 55 candidates for PNL with a single opaque kidney calculus in the calyx alone, the pelvis alone, or both the calyx and the pelvis were assigned into 2 groups. Twenty-seven patients underwent PNL with a ureteral catheter, and 28 patients underwent PNL without a ureteral catheter. Clinical outcomes were compared between the 2 groups using plain radiographs taken on the first day after the procedure. Patients had similar distributions regarding sex, age, operative time, hospital stay, past surgical history on the kidneys, and stone size. There was a significantly greater decrease in postoperative hemoglobin level in patients having PNL with a ureteral catheter [P<0.001] than in those having the procedure without a ureteral catheter. No differences were seen among patients in the 2 groups in terms of stone-free rate, and number of patients with insignificant residue, and those needing extracorporeal shock wave lithotripsy, a second PNL procedure, or transurethral lithotripsy. Percutaneous nephrolithotomy without ureteral catheterization has specific benefits: urine leakage is lower and there is no need to perform cystoscopy. Patients with a single kidney calculus are good candidates for PNL without previous ureteral catheter insertion

effect of urine and blood metabolic risk factors on calcium stone formation

In spite of vast improvements in urinary stone treatment [ESWL, PNL, ureteroscopy, etc.], metabolic workup concerning the existence of stone forming risk factors are of great importance and can lead to control and even prevention of urinary stone formation in these patients. In this analytical case-control study performed on 266 persons [110 normal persons [56 males and 54 females], 76 patients with one episode of stone formation [40 males and 36 females], and 80 patients with recurrent stone formation [40 males and 40 females]] aged between 30 to 45 [with art average of 37.6] in Shahid Doctor Labbafinejad Medical Center from May to July 1999, serum parameters and 24-hour urine parameters have been investigated and compared among the three groups. Results of this study revealed considerable differences in urinary calcium levels of these three groups, with and without considering sex [p<0.05]. Averages of 24-hour urinary calcium calculated for normal, one episode and recurrent stone formers in male groups were 159 +/- 43, 219 +/- 71, and 283 +/- 74 mg/24h respectively, and for normal, one episode and recurrent stone formers in female groups were 124 +/- 37, 190 +/- 58, and 287 +/- 152 mg/24h respectively. Although 24-hour urine citrate in females obviously showed higher values than males, there was no significant difference among the studied groups of the same sex. Levels of serum calcium, potassium and magnesium between groups of females and 24hour urine magnesium and phosphate levels between groups of males had statistical differences also [p<0.05 for all of the cases mentioned above]. According to the results obtained from this study, it was realized that in the studied society levels of 24-hour urinary calcium which are higher than 200 mg/ 24h [sensitivity 80%, specificity 94% and FPR 6.4%] and calcium creatinine ratios of 24-hour urine which are higher than 0.17 [sensitivity 7.5%, specificity 88.1% and FPR 11.9%] can be regarded as hypercalciuria. However, the results of this study should be confirmed by more general and extended studies