Evaluation of Prognostic Factors and Determinants in Surgical Sperm Retrieval Procedures in Azoospermic Patients.

INTRODUCTION: Main categorisation of azospermic is in two grups: nonobstructive azoospermia (NOA) and obstructive azoospermia (OA). We had evaluation of prognostic factors and determinants in sperm retrieval procedures in azoospermic patients. METHODS: Retrospective evaluation observed 21 selected patients with NOA and OA azoospermia, after that complete history, physical examination with ultarsound volume of testis and hormonal profile. Hormonal profile included: follicle stimulating hormone (FSH), luteinizing hormone (LH), testosteron (T) and prolactin (P) serum levels. Also karyotype and Y-deletion analysis were done and analyzed. RESULTS: 9 OA patients (42,9%) were undergone for TESE operation and 12 NOA patients (57,1%) for Micro-TESE operation. All TESE procedures were positive (100%). Micro-TESE in 12 selected NOA patients, 5 patients (41,6%) were positive and 7 patients (58,4%) negative. Patients testicular size, serum FSH and testosterone level showed correlation in success of sperm retrieval procedures. CONCLUSION: TESE is elected procedure for obstructive azospermia (OA). Micro-TESE is appropriate sperm retrieval procedurec for patients with non-obstructive azoospermia (NOA) and correlate with high FSH and small volume of testis.

The First Report from Bosnia and Herzegovina on Micro-tese Results in Azoospermic Patients.

INTRODUCTION: To present results of MicroTese procedure in treatment of male infertility in patients with azoospermia at Bahçeci BIH IVF Center during two-year period of 2013-2014. METHODS: In the stated time-period, 55 MicroTese surgeries were performed. In 52.7% of the cases, sperm cells were isolated after MicroTese surgery, and in 47.3% of the cases, there was a negative outcome of the procedure. Obtained sperm cells were subjected to cryopreservation. Furthermore, ICSI procedure was performed by use of the obtained sperm cells. RESULTS: Of 29 positive MicroTese surgeries, 21 (72.4%) resulted in clinical pregnancies. Biggest percentage of negative MicroTese procedures happened in patients with cryptorchidism and orchidopexy. CONCLUSION: MicroTese is the most precise and successful method of retrieving sperm cells surgically in men with azoospermia. Our results are within scope of results in referent world centers.

Antioxidant status in patients with bladder cancer regarding cancer stage and grade.

Objective: The imbalance of antioxidants and pro-oxidants plays a crucial role in the carcinogenesis of bladder cancer (BC). This study aimed to evaluate serum antioxidant status in patients with BC and determine its potential use in the diagnosis and progression potential considerations following histopathological assessment. Methods: A cross-sectional study included 90 patients with BC, divided into Ta, T1, and T2-T4 stage subgroups, and according to cancer progression potential, into low-grade (LG) and high-grade (HG) subgroups. The control group (CG) included 30 healthy volunteers. Antioxidant status was determined using the spectrophotometric method and standard laboratory tests. Results: Serum superoxide dismutase activity was significantly higher in BC patients regarding cancer stage in comparison to the CG (p<0.001). Catalase activity was highest in T2-T4 subgroup and was significantly higher compared to the Ta (p<0.01) and T1 (p<0.05) subgroups. Serum albumin level was significantly lower in the BC group compared to the CG (p<0.001). In addition, it was significantly lower in T2-T4 subgroup compared to T1 and Ta subgroups (p<0.01). A significant negative correlation was found between tumor size and serum albumin level only (r=-0.386, p<0.01). Catalase activity was higher in HG subgroup (p=0.009), while bilirubin level was higher in LG subgroup (p=0.035). The optimal cut-off value of catalase activity in differentiating patients with LG and HG BC subgroups was ≥11.96 IU/L, and the specificity and sensitivity were 51.1% and 82.2%, respectively. Bilirubin level, for a calculated optimal cut-off value of ≥11.95 µmol/L, had a specificity of 44.1% and sensitivity of 80.0%. Conclusion: More invasive stages of BC with greater progression potential are associated with an increase in enzymatic antioxidant activity and a decrease in non-enzymatic antioxidant capacity. It may suggest a possible role of antioxidants in the prediction and monitoring of illness trajectory.

Acute Kidney Injury Classifications in the Prediction of In-hospital Mortality and Renal Function Non-recovery.

Background: In the last two decades diagnostic criteria for acute kidney injury (AKI) were developed: Risk, Injury, Failure, Loss of Kidney Function, End-Stage Kidney Disease (RIFLE), Acute Kidney Injury Network (AKIN), and Kidney Disease: Improving Global Outcomes (KDIGO) classifications. Objective: The study aimed to determine the incidence of AKI based on the RIFLE, AKIN, and KDIGO criteria, as well as analyze their predictive value for mortality and renal function outcome. Methods: This was a single-center prospective study of patients diagnosed with AKI. Acute kidney injury was defined and classified according to the RIFLE, AKIN, and KDIGO criteria. The outcomes were renal function outcome and in-hospital mortality. Results: The incidence rates of AKI based on the RIFLE, AKIN, and KDIGO criteria were 13.4%, 14-36%, and 14.64%, respectively. Multiple regression analysis showed that higher stages of AKI according to the KDIGO criteria were independently associated with non-recovery of renal function (p=0.011). However, the predictive ability of RIFLE, AKIN and KDIGO classifications for renal function recovery was poor (Area Under the Receiver Operating Characteristics-AUROC=0.599, AUROC=0.637, AUROC=0.659, respectively). According to the RIFLE and AKIN criteria, in-hospital mortality was statistically significantly higher in stage Failure/3 (p=0.0403 and p=0.0329, respectively) compared to stages Risk/1 and Injury/2. Receiver Operating Characteristics (ROC) analysis showed that all three classifications had poor predictive ability for in-hospital mortality (AUROC=0.675, AUROC=0.66, AUROC=0.681). Conclusions: KDIGO classification is an independent predictor of renal function non-recovery. However, by ROC analysis, all three classifications have poor predictive ability for renal function outcome and mortality.

The Efficiency of Extracorporeal Shock Wave Lithotripsy (ESWL) in the Treatment of Distal Ureteral Stones: An Unjustly Forgotten Option?

Introduction The optimal management of distal ureteral stones remains a matter of debate since current guidelines favor ureteroscopy over extracorporeal shock wave lithotripsy (ESWL). We aimed to evaluate the efficiency of ESWL for distal ureteral stones and to identify factors that affect treatment outcomes. Materials and methods The retrospective study included records of 115 patients with distal ureteral stones, 5 mm to 18 mm in size, undergoing 223 ESWL sessions as an outpatient procedure. Early fragmentation and three-month follow-up stone-free rate (SFR) was assessed through radiographic imaging. Treatment was successful if there were no residual fragments or they were ≤4 mm, three months after the last session. Results The mean ±standard deviation (range) stone size was 9.68 ±3.10 (5.00-18.0) mm. The mean body mass index (BMI) was 24.3 ±2.67 (18.4-29.8) kg/m² with a significant correlation between BMI and stone size (r2 =0.324, p <0.001). Patients underwent ESWL an average of 1.7 ±1.36 times (1-5), while 68 patients (59.1%) became stone-free after one session. The overall SFR was 82.6%; for patients with stone sizes ≤10 mm and >10 mm, it was 99% and 9.4%, respectively. Cumulative SFR after the second session was 77%. In 20 (17%) patients the treatment was a failure. Complications occurred in 10.4%, while auxiliary procedures were needed in 8.7% of cases, both significantly affected by the stone size (p <0.001). The efficiency quotient (EQ) was 0.76. Treatment outcome was significantly different depending on stone size, BMI, number of sessions, complications, and auxiliary procedures (p <0.001, p =0.022, p <0.001, p <0.001, p <0.001, respectively). Univariate regression analysis identified stone size and BMI as significant predictors of treatment outcome (odds ratio (OR) 3.84, 95% confidence interval (CI): 2.31-8.97, p =0.001, and OR 1.25, 95% CI: 1.04-1.54, p =0.024, respectively). Conclusions Extracorporeal shock wave lithotripsy continues to be a safe and effective option for managing simple calculi in distal ureters with a diameter of ≤10 mm. The stone size and BMI remain significant predictors of treatment outcome.

Transrectal ultrasound-guided prostate biopsy, periprostatic local anesthesia and pain tolerance.

We have evaluated objectively pain tolerance in transrectal ultrasound-guided prostate biopsy (TRUS) using local periprostatic per rectal anesthesia as compared to the conventional method. From November 2008 to May 2009, 90 patients underwent transrectal ultrasound-guided prostate biopsy at Department of Urology, Clinical Center University Sarajevo. 90 patients who fulfilled the inclusion criteria were randomized into 3 groups of 30 patients each. Group 1 received periprostatic local anesthesia with 2% lidocaine, group 2 received Voltaren supp placed in rectum an hour before biopsy while group 3 received no local anesthesia. Pain scale responses were analyzed for each aspect of the biopsy procedure with a visual analog scale of 0-none to 10-maximal. There was no difference between the 3 groups in pain scores during digital rectal examination, intrarectal injection and probe insertion. The mean pain scores during needle insertion in group 1 receiving periprostatic nerve block and in group 2 receiving Voltaren supp were 3,10 +/- 2,32 and 5,15 +/- 2,01 respectively. In group 3 (no local anesthesia), mean pain scores were 6,06 +/- 2,95 which was found to be significantly different (p < 0,001). However, morbidity after the biopsy was not statistically different between all 3 groups. TRUS-guided prostate biopsy is a traumatic and painful experience, but the periprostatic blockage use is clearly associated with more tolerance and patient comfort during the exam. It is an easy, safe, acceptable and reproducible technique and should be considered for all patients undergoing TRUS biopsy regardless of age or number of biopsies.

Against the Odds: Management of Ureteral Calculus in Patient With Crossed Fused Renal Ectopia.

Crossed fused renal ectopia (CFRE) is a rare congenital abnormality of the urinary tract where the kidneys are fused on one side, while the ureter of the ectopic kidney crosses the midline with the normal entrance in the bladder on the contralateral side. Congenital anomalies are associated with a stone formation whose management represents a real challenge. To our knowledge, we report the second case of CFRE associated with ureteral stone, which has been successfully resolved with Extracorporeal Shockwave Lithotripsy (ESWL) and the first of its kind where a sufficient degree of stone disintegration has been achieved after a single session with a complete stone clearance during the follow-up. Radiological examination showed an inferior type of CFRE with stone in the proximal part of the ureter of the upper kidney. ESWL is an acceptable and effective treatment option in CFRE patients due to the minimally invasive approach, potentially high stone-free rate, and rare complications.

Frequency of Ventilator Associated Pneumonias in Patients in the Intensive Care Unit.

INTRODUCTION: Ventilator associated pneumonia (VAP) is defined as nosocomial pneumonia in patients who have mechanical ventilation (MV) for more than 48 hours. The diagnosis of VAP is based on radiological-microbiological examinations. In the United States, the Centers for Disease Control and Prevention (CDC) and the National Health Care Network (NHSN) have an incidence of VAP of 5.8% per 1,000 days on mechanical ventilator. AIM: In this study, we had an aim to determine the occurrence of ventilator-associated pneumonia (VAP) in patients with MV who were hospitalized in the intensive care unit. METHOD: The study was retrospective, clinical, conducted in the period from January 1, 2016 until December 31, 2016. In a one-year period, 719 patients of both sex, aged 14 to 91, were hospitalized in the intensive care unit of the Clinic for Anesthesia and Resuscitation of the University Clinical Center in Sarajevo. The study included 250 patients of both sex who had respiratory support with mechanical ventilator. No patient was excluded from the study. As a confirmation of VAP, we used microbiological reports from the patient history documentation. The results were presented statistically through tables and graphs, numerically, by a percentage, and by a mean value with standard deviation. RESULTS: Out of the 719 hospitalized patients, 250 or 34.8% underwent controlled ventilation. In 103 or 41.2% of patients some form of pneumonia was confirmed microbiologically. An average patient age on controlled ventilation was 60.4 ± 16.8 years. The mean age of a female patients who were on controlled ventilation was 63.2 ± 16.7, higher than that of male patients, which was 57.8 ± 16.6 years. The most frequent patients were over 60 years of age (52.8%). The shortest hospitalization of patients on controlled mechanical ventilation was 1 day and the longest was 120 days. Average duration of mechanical ventilation was 6.9 ± 10.5 days. CONCLUSION: VAP is a relatively common complication in patients with MV that can increase morbidity and mortality, as well as treatment costs. It is more frequent in females and in the elderly. Medical staff should provide normal maintenance of respiratory functions to a patient who is on MV, which will reduce the risk of VAP.

Serum malondialdehyde (MDA) level as a potential biomarker of cancer progression for patients with bladder cancer.

INTRODUCTION: Bladder cancer is the most common malignancy involving the urinary system. Recent research tends to emphasize the role of oxidative stress products in the carcinogenesis of bladder cancer. The level of oxidative stress can be measured by assessing the MDA levels. This study aimed to evaluate serum MDA levels in patients with bladder cancer, as well as to determine its potential role as a biomarker in the diagnosis of the disease and progression risk considerations. METHODS: The study was designed as a cross-sectional study and included 90 patients, divided into three groups with 30 patients each: Ta, T1and T2-T4 group, based on histopathological findings after transurethral resection of the tumor. The control group included 30 healthy volunteers. MDA level was determined using the spectrophotometric method. RESULTS: Serum MDA level in patients with bladder cancer [0.86 (0.78-1.05) µmol/L] was significantly higher than the serum MDA level in control group [0.70 (0.69-0.72) µmol/L] (p < 0.001). Serum MDA level in Ta group [0.73 (0.70-1.05) µmol/L], T1 group [0.85 (0.80-1.12) µmol/L] and in T2-T4 group [0.91 (0.84-1.04) µmol/L] was significantly higher than the serum MDA level in control group [0.70 (0.69-0.72) µmol/L] (p < 0.01). MDA level in T1 and T2-T4 group was significantly higher than the MDA level in Ta group (p < 0.01). No significant difference was observed in MDA level between T1 and T2-T4 group (p = NS). A statistically significant positive correlation was found between tumor size and serum MDA level in patients with bladder cancer (rho = 0.254 p < 0.01). CONCLUSIONS: The results of the present study suggest that MDA serum level might play a significant role as a biomarker in the diagnosis of bladder cancer, as well as in the monitoring of its progression.

"Second-look" Micro Testicular Sperm Extraction (MicroTESE) in Patients with Non-obstructive Azoospermia Following Histopathological Analysis.

INTRODUCTION: Microdissection testicular sperm extraction (microTESE) is considered the gold standard method for surgical sperm retrieval among patients with non-obstructive azoospermia (NOA). AIM: This study aimed to evaluate the correlation between histopathological findings after failed microTESE procedure and outcomes of the "second-look" procedure and to provide insight into the most common histopathological patterns after testicular biopsy within our population. METHODS: The retrospective study included 33 selected patients with NOA, who had undergone unsuccessful sperm retrieval. The diagnosis of NOA was made after the assessment of the patient's history data, a physical examination, semen analysis, the hormonal profile, and genetic studies. After negative sperm retrieval, histopathological report has been analyzed for "second-look" microTESE attempt. RESULTS: Five testicular histopathological patterns were found: hypospermatogenesis (9,1%), Sertoli cell-only syndrome (43%), germ cell maturation arrest (15%), seminiferous tubule hyalinization (15%), mixed pattern (21%). Y-microdeletions were detected in 5 patients, of which 3 patients showed AZFc region deletions. Only 3 patients (9,1%) underwent a "second-look" procedure after the evaluation of histopathological reports. After the stimulation therapy and "second-look" procedure, we had a positive outcome in a single patient (33,3%). Mean FSH value in patients with confirmed spermatogenesis was 17.26±3.11IU/l, while mean FSH value in patients without presence or germ cell statistically significantly exceeded and was 24.28±4.71IU/L (p=0.038). CONCLUSION: Histopathological reports following the microTESE procedure are obligatory for the proper selection of patients who are candidates for the "second-look" microTESE attempt. Patients with Sertoli cell-only syndrome and hypospermatogenesis particularly can benefit from the "second-look" procedure.

Incidental prostate cancer in patients undergoing radical cystoprostatectomy for bladder cancer.

The objective of this work is to verify the incidence of incidental prostate adenocarcinoma in patients who underwent radical cystoprostatectomy for invasive bladder carcinoma. We have retrospectively reviewed patients who underwent radical cystoprostatectomy for infiltrative bladder tumors in period between 2003 and 2007 year, 94 men with bladder cancer underwent radical cystoprostatectomy at Urology Clinic-University of Sarajevo Clinics Centre. Mean age of patients was 67 years, with age limits ranging between 48 and 79 years. Pathohistological evaluation was used for all specimens from RCP. We found that 9,57% of cystoprostatectomy specimens in patients with bladder cancer also contained incidental prostate cancer. This result was much lower than overall mean frequency of incidentally detected prostate cancer in other series of cystoprostatectomy cases (range, 23%-68%). In conclusion we recommended digital rectal examination (DRE) and prostate-specific antigen (PSA) test as part of the bladder cancer work up and complete removal of the prostate at cystoprostatectomy to prevent residual prostate cancer.

Causes of Sterility in Bosnia-Herzegovina Population.

INTRODUCTION: Infertility or sterility or barrenness is defined as a state of inability to conceive after a year of unprotected intercourse. Ovulation problems, uterine tube problems, endometriosis, uterine etiology problems, chromosomal problems which are not so rare, spermatogenesis disorders and azoospermia are stated as the most common causes of infertility. OBJECTIVE: Main objective of this research is to present most common causes of marital infertility in Bosnia-Herzegovina population. MATERIAL AND METHODS: Retrospective, descriptive- epidemiological study has been published at Bahceci IVF center in Sarajevo (Bosnia and Herzegovina). The research covered a time-period of two years. During the time-period in question, 826 marital couples from Bosnia and Herzegovina diagnosed with marital sterility approached the Center. RESULTS: Analysis of female patients as per age groups determined that the largest number of respondents belonged to the 36 - 39 age group with a total number of 293 patients, followed by 30 - 35 age group with a total number of 245 patients, and the third most frequent age group included those of ≥ 40 years of age with 179 patients in total, followed by 25-29 age group with 98 respondents. In 42% (n=350) of the couples diagnosed with marital infertility, female sterility was established as the reason, while in 36 % (n=294) of the couples, male sterility was the reason. Both marital spouses were infertile in 11% of the couples (n=92), while in remaining 11% of the couples, no diagnosis was determined and they belonged in the group of unexplainable sterility. The most common cause of sterility in women is diminished ovarian reserve (DOR), as was the case in 38.57% of respondents. This diagnosis is in direct correlation with the age of a woman. Among causes of sterility of organic and functional origin, the most common is ovarian tube problem - in 31.4% of the cases, then ovulatory problems - in 12.86% of the cases, and polycystic ovary syndrome in 6% of the cases. Other causes such as endometrioma, endometriosis and genetic factors are present in less than 2% of respondents. Regarding male sterility, problems with spermatogenesis are prevailing (decreased number and mobility of sperm cells and problems with morphology of sperm cells), oligoasthenoteratozoospermia in 81.61% of the patients. In 14.19% of the cases, azoospermia was present. CONCLUSION: All of this contributes to the negative demographic trend in Bosnia and Herzegovina. In 2008, European Parliament warned of importance of infertility treatment. In collaboration with ESHRE (European Society of Human Reproduction and Embryology), main guidelines to alleviate this problem were provided.

Preoperative kidney tumor embolization as procedure for therapy of advanced kidney cancer.

INTRODUCTION: Preoperative kidney tumor embolization is standard procedure for therapy in advanced kidney cancer. Preoperative embolization has a goal to reduce intraoperative bleeding and also to shorten the time of surgery. MATERIALS AND METHODS: We retrospectively observed 50 patients between 2000-2011, in which the preoperative embolization was performed. Mean age of patients was 64 years. All patients with preoperative embolization were compared with the group of 51 patients from Urology Sarajevo, who underwent nephrectomy without preoperative embolization. RESULTS: Symptoms that are dominating among patients were haematuria and pain. Analysis of mean size of tumors based on CT evaluation showed statistically significance in between the biggest size of tumors in group from Hamburg (9.11±3cm) and the smallest size of tumors in Sarajevo group (4.94±1.6cm) p=0.0001. Reason for this is difference in selection of patients for treatment in Hamburg from Sarajevo. CONCLUSION: Kidney as functional finishing organ is extremely suitable for transcatheter therapeutic procedures. The gold standard in the treatment of advanced and metastatic tumor is the nephrectomy. As preparation for nephrectomy in metastatic cancer total capillary embolization is performed. After embolization, surgery is shorter, procedure can be done 24-48 hours after embolization or delayed nephrectomy done 2-3 weeks after the intervention.

Bladder outlet obstruction number: a good indicator of infravesical obstruction in patients with benign prostatic enlargement?

The objective of our study was to evaluate bladder outlet obstruction number (BOON) in order to predict infravesical obstruction in patients with benign prostatic enlargement (BPE). Two hundred patients with proven BPE from daily urological practice at the Urology Department of the Sarajevo University Clinical Centre were covered by a prospective study in period 2009-2011. All patients completed International Prostatic Symptom Score, their mean voided volume urine was determined from frequency-volume chart and their prostate volume was determined by transabdominal ultrasound. Subsequently, the patients had free uroflowmetry and they underwent complete urodynamic studies. BOON was calculated using the formula: prostate volume (cc)-3 x Qmax (ml/s)-0.2 x mean voided volume (ml). A satisfactory area under the curve (AUC) was obtained for the prediction of obstruction according to bladder outlet obstruction index, Schaefer obstruction class nomogram and group specific urethral resistance factor , with AUC of 0.83 (p<0.001). Following the comparison of different cut-off values of BOON according to the obstruction, the BOON >-20 has been found to be the most accurate obstruction indicator (sensitivity 76.5% and specificity 68.2%), with posttest probability of 77%. The BOON may be used in daily urological practice as a valid, non-invasive indicator of infravesical obstruction in patients with BPE, with a possibility of correct classification of obstruction in approximately 75% of the cases. Transabdominal ultrasound has shown to be applicable to the BOON formula in determining prostate volume.

Extracorporeal shock wave lithotripsy and intravenous contrast media application for localization of radiolucent calculi.

BACKGROUND AND PURPOSE: The present study was carried out to compare the efficacy of ESWL treating radiolucent ureteric calculi visible in the ureter after application of contrast media. MATERIAL AND METHODS: Medical records of 47 patients who had verified ureteric calculi by intravenous urography and retrograde pyelography were included in this study. Patients had undergone ESWL treatment after application of contrast media. Patients were divided in two groups, different in focusing the shock waves either at the end and below contrast shadows of the column of contrast medium visible in the ureter. 23 patients from group 1 were treated with shock waves focused on the end of contrast medium column and 24 patients from group 2 were treated with shock waves focused below contrast shadow of the contrast column. RESULTS: The stone free rate after 1 month were 9% and after 3 months were 14% greater in group 2 (89%) than in group 1 (75%). There were no allergic reactions to the contrast medium. Distributions of age, gender, treatment and diagnostic methods had been in both groups compared. CONCLUSION: ESWL of radiolucent ureteric calculi with application of contrast media is effective and safe. Shock waves focused below contrast shadow of the contrast column had better stone free rate than focusing at the end of the column.

Effects of extracorporeal shockwave lithotripsy on renal vasculature and renal resistive index (RI).

OBJECTIVE: It is known that ESWL can promote acute renal injuries and long-term complications of renal vasculature. Effects on renal vasculature can be evaluated by color Doppler ultrasonography measuring renal resistive index (RI). This prospective study aimed to determine the influence of number of delivered SW-s, used kV and changes in renal resistive index. PATIENTS AND METHODS: Total of 60 normotensive patients, 38 males (63%) and 22 females (37%), with renal stones 6-18 mm in size were included in this study. Median age was 42.3 years (range 22-55). RI was measured at interlobar artery before, 1, 3, 5 and 30 days after treatment on treated and contra lateral non-treated kidney. Patients were divided in two groups: Group I (N=25) received 2000 SWs; 0-2 units; (0.5 unit each 500 SWs) Group II (N=35) received 4000 SWs, 0-4 units; (0.5 unit each 500 SWs). RESULTS: In treated kidneys RI significantly increased first and second day after treatment from 0.62 +/- 0.05 at baseline to 0.67 +/- 0.05, p < 0.001 at first and 0.66 +/- 0.05, p < 0.007 on the second day after treatment. Increase of RI seven days after treatment is not significant (0.62 +/- 0.05). The contra lateral, non-treated kidney showed significant changes in RI only first day after treatment (0.64 +/- 0.05), p < 0.01. One month after the treatment RI is on normal values in both kidneys. CONCLUSIONS: Resistive index-RI is important parameter in evaluation of renal vasculature. Patients treated by ESWL showed a temporary increase in RI two days after the treatment and only first day in contra lateral non-treated kidney--probably caused by release of substance with vasoconstriction properties (need further investigations).