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Clinical epidemiology is the science and method of studying the optimal decisions in clinical medicine, taking into consideration the epidemiological characteristics of the patient and his/her external clinical environment, the disease involved, and factors and procedures to which the patient is exposed in his/her clinical environment, specially clinical actions. Research should be a systematic process, organized and objective, aimed to answer the question posed. Systematic means that the scientific method is applied, for that a hypothesis or work objective is formulated from observations or established knowledge about a topic, data are collected following a pre-established design, and, once analyzed and interpreted, conclusions are obtained which will modify or add new knowledge to the previous, and a new cycle starts again. Organization means that all members in the research team know perfectly what to do during the whole study, apply the same definitions and criteria to all participants, and act in identical way in front of any doubt. To achieve this, it is mandatory to write a protocol specifying all details related to the study. The meaning of the word objective is that conclusions obtained are not based on subjective impressions but on facts that have been observed, measured, and analyzed, and that any prejudice the study responsibles could have is avoided during its interpretation.

Objectives: To perform an update in such an infrequent pathology and to report our own experience., Methods: We report two new cases and review the national and international literature., Results: We report two cases of ipsilateral metanephric adenoma and clear cell carcinoma. The first case, metachronous, was detected after 15 months of follow-up in a patient who underwent partial nephrectomy due to clear cell carcinoma. The second one, synchronic, was incidentally discovered in the surgical specimen., Conclusions: Metanephric adenoma is as infrequent neoplasia; its diagnosis is histological, being difficult to suspect by complementary diagnostic tests, so that most cases undergo surgical treatment in spite of its benign character.

Objectives: To evaluate the influence of receptor's age on the outcomes of kidney transplants with organs from non heart beating donors., Methods: Observational study of the historic cohort of 570 kidney transplants performed at the Hospital Clínico San Carlos between 1991 and 1999. Receptor's were divided into two age groups, group 1 younger than 50 years, and group 2 older than 50 years. All organs where harvested from non heart beating donors., Results: We studied 110 kidney transplants coming from non heart beating donors; 52 belonged to group 1, and 57 to group 2. Three-year patient survival for receptor's younger than 50 years was 100%. The probability of three-year survival for receptor's older than 50 years was 79.39% (p 0.07). Graft survival was 88.46%, 86.54%, and 86.54% at 12, 24, and 36 months respectively for receptor's younger than 50 years. When receptors were older than 50 years the probability of functioning graft in the same periods of time was 89.20%, 89.20%, and 86.32% respectively., Conclusions: Receptor's age doesn't seem to influence graft survival when kidneys from non heart beating donors are used.

Objective: To present our experience with renal collecting duct carcinoma and review the literature., Methods: We reviewed our experience with collecting duct carcinoma of the kidney. We found 6 cases out of 176 nephrectomies (3.4%), which accounts for one of the largest series reported in the literature. The radiological, histological and immunohistochemical findings are analyzed., Results: The histological and immunohistochemical findings showed a specificity for high molecular weight cytokeratins and Ulex europeaeus but the imaging findings were not distinct from those of other renal tumors. According to the anatomopathological findings, we have classified the patients into three groups with three distinct courses. All patients underwent radical nephrectomy and one patient received adjuvant therapy., Conclusions: We have identified a subgroup of low grade collecting duct carcinoma of the kidney with a particularly favorable behavior in two patients of our series. At 56 and 41 months' follow-up, both patients remain disease-free. As reported in the literature, patients with high grade and stage collecting duct carcinoma of the kidney have a poor outcome. They develop severe complications and die less than one year after the diagnosis, despite adjuvant immunotherapy.

Objective: To describe a case of cutaneous horn of the penis and review its clinical and histological features., Methods: The clinical and histological features of cutaneous horn of the penis are described., Results/conclusions: Cutaneous horn of the penis is an uncommon lesion that is diagnosed without difficulty. Treatment is by surgery with sufficient margins due to its possible association with malignant lesions.

Objective: Since its discovery as a marker for prostate cancer, there have been many attempts to enhance the diagnostic efficacy of the prostate specific antigen (PSA). Among these are the studies that analyze the behavior of different forms of serum PSA bound to different antiproteases, such as alpha-1-antichymotrypsin, which forms the complexed PSA (PSA-c). This study analyzed the utility of PSA-c to enhance specificity without altering sensitivity in comparison to total PSA (PSA-t)., Methods: From September 1998 to March 1999, blood samples were obtained from 96 patients that had undergone a prostate biopsy due to a suspicion of prostate cancer. PSA-c, PSA-t (Technicon Immunol system, Bayer) and PSA-c/PSA-t ratio were analyzed in these patients., Results: ROC curves were plotted and the optimal cutoffs were found for which the specificity was higher for PSA-c (44.6% [CI 95%, 32-57]) versus PSA-t (35.4% [CI 95%, 25-49]) and the PSA-c/PSA-t ratio (38.5% [CI 95%, 27-51]) while maintaining a similar sensitivity index (90%). PSA-c showed similar results for other values of sensitivity., Conclusions: PSA-c was found to improve specificity in comparison to PSA-t and PSA-c/PSA-t ratio. PSA-c determination could avoid unnecessary biopsies without altering sensitivity; i.e., the same number of prostate cancers will be detected.

Objective: To determine the loss of heterozygosity (LOH) on 9p21 (locus D9S1747) in patients with renal carcinoma by analysis of microsatellite polymorphisms., Methods: 40 patients with sporadic renal cancer were studied. LOH on 9p21 was performed by analysis of microsatellite polymorphisms., Results: 23.7% showed LOH on 9p21. No correlation was found between this genetic alteration and tumor features., Conclusions: LOH on 9p21 was found in 23.7% of the patients in this series. LOH was found in 26.9% of renal cell carcinomas, 25% of papillary carcinomas and 25% of Bellini duct carcinomas. LOH was not found in the other histological types.

Introduction: Aiming to preserve the bladder in patients with infiltrative carcinoma of the bladder and to offer patients improved quality of life with no detriment for survival, a therapeutical protocol was set up., Material and Methods: Between August 1988 and January 1997 63 patients with stage T2 and T3a infiltrative carcinoma of the bladder, with no metastasis or node extension detectable with imaging techniques were treated in our unit. 45 of these patients met all protocol criteria and were given 3 neoadjuvant chemotherapy courses with MVAC (methotrexate, vincristine, adriamycin, cisplatin)., Inclusion Criteria: age under 75 years, Karnofsky greater than 50%, leucocytes greater than 2,500 cell/mL and platelet greater than 100,000/mL. Following chemotherapy, re-assessment was performed through lab tests, chest X-rays, abdomino-pelvic CT, bone scanning, cystoscopy, multiple randomized biopsies, tumoral bed scar resection and resection of relapsed urothelioma. Patients with complete remission were given radiotherapy. Those showing stabilisation of progression were proposed to undergo cystectomy. Fisher's test or chi 2 test were used for the comparison of qualitative variables. The survival analysis was performed using the Kaplan-Meier method. The curves comparison was done with Breslow's exact test. A Cox's proportional risk method allowed to calculate the relative risks together with their 95% confidence interval., Results: 53.7% patients included in this protocol showed complete remission, 41.5% stable disease and 4.9% progression. 62.2% of patients were given radiotherapy versus 17.8% who underwent cystectomy. 20% received other therapies after rejecting both cystectomy or radiotherapy. Median follow-up was 43.38 months. Overall median survival was 96 months. The accumulate probability of survival at 4 years was 79%. 50% patients with complete clinical response relapsed during follow-up. Tumoral stage of those who relapsed was lower than the initial one in 63.7% cases, remained the same in 18.2%, and higher in 18.2%. With regards to grading, 66.7% patients had lower grading at relapse if tumour was initially grade 2. For those with initial tumour grade 3, only 20% had a lower grade., Conclusion: 64.4% patients retained their bladder. In 26.7% there was demonstrable metastatic disease. No differences were seen in the distribution or survival time based on the different treatment given after chemotherapy (p = 0.22). Patients with complete remission after chemotherapy have greater actuarial survival which is statistically significant (p = 0.04).

Methods: From November 1992 to November 1993, a prospective study was conducted on 20 controls and 61 patients with bladder carcinoma. EGFR expression was determined by radioimmunoassay and the correlation of the results of histological analysis and the clinical course was analyzed. The follow-up period was from November 1992 to July 1998. The association between qualitative variables and the x2 or Fisher exact test was compared using the hypothesis of the proportional ordinal trend for the ordinal variables, and the quantitative variables were analyzed using Student's t test and/or variance analysis (ANOVA). Survival was analyzed by the Kaplan-Meier method and comparison was performed using the Breslow exact test. The Cox proportional hazards regression model was utilized. The SPSS software for Windows 7.0 was used for the analysis., Results: The EGFR values were higher for patients with bladder carcinoma than in controls (14.48 vs 2.54 fmol/mg of protein). EGFR values were higher in patients with superficial bladder tumor than in those with infiltrating tumors (27.03 fmol/mg vs. 10.05 fmol/mg of protein; p = 0.000). Poorly differentiated tumors showed higher values of EGFR (6.73, 14.48 and 17.07 fmol/mg of protein for grades I, II and III, respectively; p < 0.05). The EGFR values were higher in patients that died from cancer during follow-up (64.8) than in those who died from other causes (47.5) and those who are alive and on follow-up (42). An increase in EGFR values did not carry a risk of death from cancer (p = 0.1269; ns). Analysis of the grade of tumor differentiation showed that for the more aggressive tumor grade, a positive EGFR was a sign of reduced survival. Survival in patients with superficial and infiltrating tumor did not appear to change significantly according to the EGFR value. EGFR determination was not useful in predicting recurrence and increased EGFR values did not correlate with a higher risk of recurrence., Conclusions: 1) The normal pattern of EGFR could not be established. 2) EGFR was not useful in identifying subgroups at risk of death. 3) Knowledge about these proteins synthesized by oncogenes offers new possibilities in the treatment of cancer.

Objective: To determine the utility of p185 oncogene in the biological characterization of transitional cell carcinoma and in the prediction of recurrence, and to analyze survival at 5 years mean follow-up., Methods: A prospective clinical cohort study was conducted on 81 patients. Tissue specimens were obtained between November 1992 and November 1993. The study comprised two groups: nontumoral bladder tissue specimens from 20 patients (group I) and tissue specimens from 61 patients with bladder carcinoma (group II). p185 expression was determined by enzyme immunoanalysis (EIA). A statistical analysis of the results was performed., Results: p185 oncoprotein levels were higher in patients with recurrence (1098.97 HNU/mg protein vs. 924.54 HNU/mg). Although higher levels of p185 were found in the patients that had died vs those who are alive, the differences were not statistically significant for overall survival or stratification by tumor grade or infiltration (p = 0.556; ns)., Conclusions: Determination of p185 oncoprotein was found to be useful in the prediction of tumor recurrence at 5 years mean follow-up.

Objective: To review our experience in the diagnosis and management of ureteral injuries secondary to obstetric and gynecologic procedures., Methods: During the last 25 years, 42 patients were treated at our center for iatrogenic ureteral injuries (45 renal units) associated with obstetric and gynecologic procedures, principally hysterectomy via the abdominal approach (29 cases). The injury was diagnosed in the immediate postoperative period in 21 of the 42 cases. Surgical management was frequently by ureteroneocystostomy. Patient follow-up ranged from 3 months to 11 years., Results: Good results were obtained in 83.3% of the cases., Conclusions: Ureteral injuries detected intraoperatively should be immediately repaired. For those diagnosed postoperatively, management by retrograde or antegrade catheterization and/or US or CT-guided percutaneous nephrostomy should be attempted before performing surgery.

Objectives: 1) To determine p53 expression in urinary wash cytology by immunohistochemistry in patients with superficial transitional cell carcinoma of the bladder and controls; 2) to correlate p53 in urinary wash cytology and anatomopathological characteristics of the bladder tumors analyzed; 3) to determine the utility of p53 expression in urinary wash cytology as a prognostic factor; and 4) to identify a subgroup of patients with superficial tumors of worse prognosis in order to improve control of the evolution of the tumor and treatment., Methods: From 1993 to 1998, 141 cases were studied; 32 controls comprised group I and 109 (38 primary and 71 recurrence) patients with transitional cell carcinoma of the urinary bladder comprised group II., Results: In group II, 29.5% were positive for p53 in urinary wash cytology, while no positive cases were found in group I. A total of 104 valid data were analyzed, which showed a higher percentage of p53-positive cases in grade III tumors (44.4%). Statistical analysis showed the percentage of p53-positive cases increased with tumor grade in a linear trend (p = 0.17). The recurrence rate in the p53-positive was 20% greater than in the p53-negative cases. Tumor progression was three times higher in the p53-positive than in the p53-negative patients., Conclusions: The application of biomolecular knowledge to cytology is a useful complement in follow-up of patients with superficial transitional cell carcinoma of the bladder and offers additional parameters to distinguish benign and malignant cells. Immunohistochemical determination of p53 in urinary wash cytology identifies patients with superficial tumors with a worse prognosis.

Objective: Mutations in the TP53 gene are frequently detected in some types of malignant tumors (bladder, prostate, kidney, lungs, breast, colon and rectum). This study analyzed the utility of semi-quantitative determination of p53 in transitional cell carcinoma of the bladder by an immunohistochemical technique and evaluated the results at 5 years., Methods/results: A prospective clinical cohort study was conducted on 81 patients. The study comprised two groups: nontumoral bladder tissue specimens from 20 patients (group I) and tissue specimens from 61 patients with bladder carcinoma (group II). In both groups the tissue specimens were obtained between November 1992 and November 1993, and during the follow-up period until July 1998. p53 expression was determined by a semi-quantitative method based on an immunohistochemical technique (NCL-p53-DO7, Novocastra)., Conclusions: p53 oncoprotein was not found to be useful in the characterization of carcinoma of the urinary bladder.

A survey-based comparative study was conducted to evaluate the changes on the prostate pathology in two male populations separated by a time interval of two years (1st and 3rd Week of Prostate Health). A total of 2056 respondents in the 1st Week, and 2126 in the 3rd Week were evaluated. The questionnaire included questions relative to prostate awareness, impact of urinary complaints on daily like activities, Spanish validated IPSS and selective questions for prostate patients. The comparison between both surveys disclosed visits to the urologist at earlier age and longer-standing symptoms. The most prevalent symptoms continue to be decreased calibre of the urinary stream, pollakiuria and urgency. IPSS/L and IPSS/age ratios remained unchanged. There was increased number of visits by mildly symptomatic patients (IPSS < 8), increased periodical revisions, and in the number of patients seen and treated by the urologist. A significant approximation to the diagnostic testing criteria established by the WHO for BPH was demonstrated. The number of patients who received treatment raised and there was also a significant improvement in the outcome. Comparative populational studies could allow to assess changes in the awareness status of the prostate, changes in symptomatic levels and quality of life of the population requesting health care, as well as changes in the diagnostic and therapeutical schemes in patients suspected of having BPH.

Objective: To evaluate the clinical efficacy of doxazosin for 6 months in the treatment of benign prostatic hyperplasia (BPH)., Methods: A prospective clinical and uroflowmetric study was conducted on 65 males with BPH treated with doxazosin 4 mg daily for 6 months. Patient mean age was 66.7 years (range 45-79). Clinical evaluation (IPSS and andrologic data) and blood analyses were performed before and after treatment. IPSS data were obtained according to the WHO validation and Spanish translation., Results: A significant improvement was found between the mean pre- and post-treatment IPSS scores (19.8 +/- 4.8 vs 11.9 +/- 4.6; p < 0.001). Maximum flow rate before treatment was 9.13 ml/sec, which increased to 16.23 ml/sec after treatment (p < 0.001). Postvoid residual urine dropped from 21.7% to 12.5% (p < 0.01). All the patients were normotensive before (135.9 mean systolic and 78.9 mean diastolic blood pressure) and after treatment (135.4 mean systolic and 77.8 mean diastolic blood pressure). Mean heart rate was similar before and after treatment (71.9 +/- 5.8 vs 71.8 +/- 5.9). A relationship between low IPSS score before treatment and urinary symptoms improvement was demonstrated (coeff. -0.45939). No relationship was found between prostate volume (digital rectal examination or transabdominal ultrasound) and improvement in the IPSS score. No statistical relationship was found between the IPSS and postvoid residual urine or peak flow. No modifications of sexual activity was demonstrated with doxazosin treatment. Pre- and post-treatment blood analytical data fell within the normal ranges. Transient side effects were observed in 12 patients (20%): headache in 6 patients (10%), fatigue in 6 (10%), dizziness in 3 (5%) and somnolence in (5%)., Conclusions: Doxazosin, at a daily dose of 4 mg daily for 6 months, is a safe and effective treatment in patients with BPH.

Objective: To report two rare cases of persistent müllerian duct syndrome., Methods/results: Two patients with normal chromosome studies (46, XY) are presented. The radiological evaluation showed structures compatible with those of the müllerian duct. These structures were completely excised with excellent results. The histological findings confirmed the clinical diagnosis., Conclusions: Persistent müllerian duct syndrome is a rare form of male pseudohermaphroditism that presents difficulties in making the differential diagnosis from other conditions with a different etiopathogenesis and that are not completely defined.

Objective: The present study analyzes the main clinical types of urinary incontinence in the elderly population and its clinical-urodynamic correlation to facilitate definitive diagnosis., Methods/results: The study was conducted in 948 elderly patients (382 male, 566 female; mean age 72.4 years) with urinary incontinence. Patient clinical and urodynamic records were reviewed. The most common clinical types were urge-incontinence (56.4%) and incontinence with coughing associated with urge-incontinence (32.3%); the latter type was the most common in women. The most frequent urodynamic diagnoses were isolated bladder instability (29.9%), followed by obstruction (15.6%) and stress incontinence (14%)., Conclusions: The most common symptom in bladder instability was urge-incontinence, while incontinence with coughing was found to be the most common symptom in urinary stress incontinence. A significant correlation was found between the postvoid residual urine and the main urodynamic diagnoses. Multivariate analysis showed that classification by clinical types of incontinence together with measurement of residual urine can facilitate diagnosis, although this approach has a low sensitivity for the main forms of isolated incontinence. The mixed forms require a urodynamic study.

Objective: Mutations in the p53 gene are frequently detected in some types of malignant tumors (bladder, prostate, kidney, lung, breast, colon and rectum). This study analyzed the utility of p53 quantitation in transitional cell carcinoma of the bladder and evaluated the results at 5 years., Methods: A prospective clinical cohort study was conducted on 81 patients. The study comprised two groups: nontumoral bladder tissue specimens from 20 patients (group I) and tissue specimens from 61 patients with bladder carcinoma (group II). In both groups the tissue specimens were obtained between November 1992 and November 1993, including the follow-up period until July 1998. p53 expression was determined by a quantitative method based on immunoluminiscence (LIA-MAT p53)., Results: p53 expression was higher in bladder carcinoma than in healthy urothelial tissue; higher values of p53 were found for infiltrating and undifferentiated tumors. The p53 values were higher in patients with tumor recurrence than in those without (NS). The Bonferroni multiple comparisons test showed a higher mortality in patients with p53 > 0.9 than in patients who are alive or have died from other causes (p = 0.000)., Conclusion: The results show that p53 LIA-MAT is an independent prognostic factor at a cutoff of 0.9 and permits identification of a subgroup of patients at high risk.

Objective: To report our experience with the management of arterial priapism by embolization., Methods: Two patients with arterial priapism secondary to perineal trauma are described. Diagnostic evaluation included intracorporal blood gas, echo Doppler and selective pudendal arteriographic assessment. Treatment was by selective autologous embolization., Results: Detumescence was achieved and control follow-up evaluation at 12 and 24 months demonstrated normal erectile function., Conclusions: In our view, selective embolization is an effective treatment for arterial priapism arising from perineal trauma.

Objective: The development of in vitro cell tissue culture techniques has provided most of the current knowledge on the physiology of both normal and tumor cells. The results of cell culture studies using nephrectomy specimens are presented., Methods: Surgical specimens from 7 patients (3 males, 42.9%; 4 females, 57.1%) aged 43-79 years (mean 62.14), who had undergone nephrectomy for renal adenocarcinoma between April 1997 and February 1998 were utilized. The tumor cell samples were obtained during surgery, after the kidney had been excised. The samples were cut, washed in a balanced saline solution and enzymatically dissociated in a trypsin solution (0.1% Hank's solution) for 30 minutes at 37 degrees, centrifuged, placed in Multiwell plates, covered with 0.1 mg/ml polylysine (ICN) or 3 mg/ml collagen S (Boehringer) and cultured in RPMI 1640 (Sigma) supplemented with 5% fetal calf serum (reagent), which was changed every 2-3 days for one month. After the culture had developed, samples were fixed in 70% ethanol and stained with hematoxylin-eosin for cell identification. Cell types were identified by cytokeratin analysis., Results: The histological types were: clear cell renal adenocarcinoma in three cases (42.9%), renal oncocytoma in two (28.6%), mixed cells renal adenocarcinoma in one (14.3%) and papillary carcinoma in one case (14.3%). Polylysine and collagen were found to be good substrates for normal and tumor cell culture. Polylysine was found to be a better substrate for epithelial cells; there were less epithelial and more mesangial cells in the collagen substate. The positive cytokeratin expression (a marker for intermediate filaments) corroborates the well-known epithelial origin of renal cell carcinoma. Epithelial cells from normal kidney grew well in the culture medium. Mean cell survival was 30.83 days (range 15-50). To evaluate the viability of the culture, positivity for a neutral red stain was used as marker for good metabolic activity after one month. All cultures that survived for more than one month (5 of 7) stained positively., Conclusions: The study and development of human cell lines is useful to analyze the metabolic aspects of renal carcinoma. Cell cultures permit conducting genetic and molecular studies and investigating the radio and chemosensitivity of renal carcinoma in vitro.

Objective: Renal cancer accounts for 2% of tumors. The most common chromosome abnormality found in renal cancer is the loss of heterozygosity (LOH) on the short arm of chromosome 3 (3p), which suggests that near the gene responsible for von Hippel-Lindau disease, there may be one or more tumor suppressor genes between 3p14 and 3p21 with a relevant role in the development of renal cancer., Methods: 41 patients with sporadic renal cancer were tested for three microsatellites mapped to the short arm of chromosome 3 (3p14.1-3p14.3, 3p21.2-3p21.3 and 3p25) by polymerase chain reaction. The results were compared with patient habits and tumor features., Results/conclusions: 43.9% of the patients showed LOH on at least one locus. Thirty-four percent showed LOH only on one locus, 4.9% on two loci and 7.3% on the three loci tested. All the patients who showed LOH on 3p21 had a tumor size greater than 25 mm. There is a risk 1.76 times higher of no loss in tumors less than 25 mm in size than in tumors greater than 25 mm (Cl 95% 1.33-2.33).

Objective: To analyze the medium-term outcome of en bloc transplantation of pediatric kidneys into adult patients, including the incidence and type of surgical complications., Methods: From November 1991 to December 1997, we performed 37 en bloc transplantation of pediatric kidneys into adult patients. The kidneys were harvested from donors less that 3 years old and/or weighing 15 kg. The mean follow-up was 24 months. Grafting was achieved by end-to-side anastomosis of the donor cava to the receptor external iliac and the aortic patch to the external iliac artery., Results: Three grafts failed, probably due to hilar torsion; the remaining were initially functioning well. Seven transplant removal were performed; 6 were due to thrombosis. The actuarial graft survival was 89.1% at one month, 80.83% at 12 months and 80.83% at 24 months., Conclusions: The medium-term results of en bloc transplantation of pediatric kidneys into adult patients were excellent and demonstrate the efficacy of this type of grafts. Arterial and venous thrombosis were the most important complications, quantitatively and qualitatively.

Objective: To analyze the outcome of renal transplantation in patients more than 65 years old., Methods: From 1991 to 1997, 83 renal transplants were performed in patients aged over 60 years at our institution; 20 of these patients were more than 65 years old. The control group comprised graft recipients under than age from the 477 cases that had undergone transplantation during the period 1980-1996. Graft donor selection was done according to standard practice. The immunosuppression protocol changed over time; 5 patients received triple therapy and another 15 patients received quadruple sequential immunosuppression therapy., Results: The mean age of the recipients was 66.8 years (range 65-72); 9 patients required dialysis after renal transplantation. Patients aged over 65 years had a 94% survival at 6 months, 88% at 12 months, and 88% at 48 months, whereas the survival rates for the control group were 96%, 95% and 87% for the respective time periods. Graft survival was 95% at one month, 90% at 3 months and 74% at 48 months versus 93%, 87% and 78% for the control group., Conclusion: Patients more than 65 years old with chronic renal failure and who are on dialysis can benefit from renal transplantation.

Objective: To determine which urodynamic model best describes lower urinary tract dynamics during the voiding phase., Methods: A pressure-flow study was conducted in 211 adult males. The urodynamic data from the pressure-flow study were modelized to a multivariate analysis with a descriptive design. Three descriptive models of urethral resistance were proposed: a linear model that consisted of the detrusor pressure at the end of voiding and the pressure-flow plot slope, and two quadratic models with one parameter [urethral resistance average (URA)] or two parameters [opening detrusor pressure and passive urethral resistance ratio curvature (PURR)]. Bladder contractility was defined by two parameters: power at maximum flow rate (Pw) and maximum power/bladder surface (Wmax). Voiding volume was included in all models as control variable. The best model was defined as that which explains a higher percentage of observed maximum urinary flow rate, the most widely utilized datum in the urodynamic studies of the adult male., Results: The model that consisted of the URA and Pw was found to be the best. We observed an interaction between URA and voiding volume (at higher voiding volume the decrease of the maximum urinary flow due to URA was found to be greater)., Conclusions: The URA was found to be the parameter that best describes urethral pressure. Variations in the maximum urinary flow rate is better described by the Pw than by the Wmax.

The presence of neoplasms in patients with renal transplant in a higher frequency than in general people is known since a long time. The most frequent tumours were the skin tumours, followed by other tumours common in immunosuppressed patients. The ain of this work has been study the frequency, type, diagnosis, treatment and evolution of the urinary system tumours in patients with renal transplant and an exhaustive review of literature. We have found 11 tumours of the urinary system over 57 tumours in 41 patients, with a frequency 26.8%. 6 were kidney tumours, 3 of prostate and 3 of the bladder. We have analyzed the incidence, diagnosis, treatment and evolution of tumour and its effects on the graft. We believe that the posttransplant follow-up of the patient, overcoat in males, who have tumours in more frequency, is important for the early diagnosis.

Objective: To analyze the terminological and conceptual aspects of post-surgical vesicourethral neurogenic dysfunction, as well as the etiological, clinical and urodynamic data., Methods: We conducted a clinical and urodynamic study on 152 patients, 103 males (67.8%) and 49 females (32.2%), mean age 52.04 years, who presented with neurogenic bladder dysfunction after surgery or exploratory maneuvers. The preoperative urodynamic study was available in 123 cases (80.9%). The study protocol included patient clinical history, neurological physical examination to determine the level of the lesion and a complete urodynamic study (Wiest 8000), including selective sphincteric electromyography., Results: The study group comprised 59 patients (38.8%) who had undergone a neurosurgical procedure (25 patients had a disc hernia), 45 (29.6%) had undergone digestive surgery (abdominoperineal resection of the rectum was performed in 37 patients), 24 (15.7%) had undergone surgery for trauma (11 patients had a vertebral fracture), 12 (7.8%) had a urological procedure, 4 (2.6%) were referred from Gynecology and Obstetrics, 4 (2.6%) had received anesthesia or had undergone neurological explorations, 3 (1.9%) had undergone vascular surgery and 1 patient (0.6%) had received radiotherapy. The neurological lesions were supramesencephalic in 4 patients (2.6%), cervical in 14 (9.2%), dorsal in 6 (3.9%), lumbar in 6 (3.9%), conus medullaris in 17 (11.1%), cauda equina in 44 (28.9%) and peripheral in 61 (40.1%). Urinary incontinence (55 patients, 36.1%) was the most frequent cause for consultation. Other symptoms were difficulty in voiding (45 patients, 29.6%) acute urinary retention (33 patients, 21.7%), involvement of urge to void (33 patients, 8.5%) and daytime and/or nighttime frequency (6 patients, 3.9%). Acute urinary retention was statistically significant in the males (p < 0.05) and urinary incontinence in the females (p < 0.01). Incontinence was the most common symptom in patients submitted to radical prostatectomy. The correlation between conus medullaris lesion and acute urinary incontinence was significant (p < 0.001). Patients had referred symptoms for a mean of 8.5 +/- 30.7 months. Bladder reflex on cystomanometry was absent in 100 patients (65.8%) and present in 52 (34.2%). Thirty (57.6%) had voluntary and 22 (42.3%) had involuntary reflex (hyperreflexia). On electromyographic evaluation, baseline activity was normal in 84 patients (65.2%), diminished in 34 (26.3%) and absent in 11 (8.5%). The types of potentials were: normal in 35 cases (28.6%), positive waves 16 (13.1%), fibrillation in 24 (19.6%), polyphasic in 38 (31.1%), potentials with increased duration and/or amplitude in 8 cases (6.5%) and repetitive discharges in 1 case (0.8%). The following types of neurogenic vesicourethral dysfunctions were found: neurogenic shock in 10 patients (6.5%), lower motor neuron dysfunction in 109 (71.7%), upper motor neuron dysfunction in 22 (14.4%) and mixed motor neuron dysfunction in 11 (7.2%)., Conclusions: The term 'postsurgical vesicourethral neurogenic dysfunction' overcomes the limitations of previous terminology (e.g., iatrogenic neurogenic bladder) since it refers to the neurogenic dysfunction that presents after surgery regardless of the previous study. It is possible to obtain a clinical and urodynamic map of this condition whose etiology can be found fundamentally in disc hernia surgery (neurosurgery) and abdomino-perineal resection of the rectum (digestive surgery).

Objective: To determine the urodynamic characteristics of urinary incontinence after radical retropubic prostatectomy., Methods: We conducted a clinical and urodynamic study on 25 patients who had undergone radical retropubic prostatectomy due to localized prostate adenocarcinoma., Results: 68% of the patients completely recovered urinary continence. The maximum rate of urinary continence recovery was found between the third and fourth month postprostatectomy. A relationship was demonstrated between preoperative hormone blockade, duration of the surgery and urinary continence. Videocystography demonstrated an incompetent proximal continence mechanism in all radical prostatectomy patients. All incontinent patients presented stress urinary incontinence. Denervation potentials of the periurethral sphincter was demonstrated by electromyography in 80% of incontinent patients. These potentials were not present in the continent patients. Reinnervation potentials were present in 50% of the continent patients and in 20% of the incontinent patients (significant differences). No relationship was found between other urodynamic data and post-radical prostatectomy urinary incontinence., Conclusions: The surgical difficulty influences the preservation of urinary continence. A high percentage of patients submitted to radical prostatectomy recover urinary continence with time. Urinary incontinence following radical prostatectomy is based on the distal sphincteric mechanism. Patients who remain incontinent four months postoperatively and with electromyographically demonstrated denervation potentials of the periurethral sphincter can be considered to be candidates for treatment of incontinence without waiting any further.

Objective: To evaluate bladder and urethral sphincter reinnervation mechanisms during long-term follow-up in patients with lower motor neuron neurogenic bladder following neurological surgical injury., Methods: A urodynamic study was conducted in 30 patients (21 male and 9 female; mean age 53.4 years) with lower motor neuron neurogenic bladder dysfunction arising from neurological injury sustained during surgery. The protocol included cystometry and periurethral electromyography (EMG) at 3, 6, 9, 12 months and once a year for 7 years, and videocystography at 3, 12 months and once a year for 7 years. Functional parasympathetic (detrusor) reinnervation criteria were cystometric. Functional sympathetic (bladder neck) reinnervation criteria were cystographic. Functional pudendal (periurethral sphincter) reinnervation criteria were electromyographic (increase of polyphasic and long amplitude and/or long time potentials)., Results: Detrusor reinnervation was demonstrated in 6 male patients (20%) with an average period of 44.6 months. Pudendal reinnervation was demonstrated in 17 patients (77.2%) with an average period of 17.6 months. EMG potentials were polyphasic in 17 cases and long amplitude/long time potentials in 3 cases. Sympathetic reinnervation was demonstrated in one patient (16.6%) at 60 months., Conclusions: Functional pudendal reinnervation of the periurethral sphincter was more frequent and was demonstrated earlier than reinnervation in vegetative elements (parasympathetic and sympathetic). Parasympathetic reinnervation had long-term therapeutic implications. Ongoing urodynamic assessment in patients with lower motor neuron neurogenic bladder following abdominoperineal resection or intervertebral disc prolapse surgery is warranted. Sympathetic reinnervation was scanty and was demonstrated later in relation to distal postganglionic fibers.

Objective: To analyze the incidence of tumors in renal graft recipients, the course, treatment and its effect on the graft and patient., Methods: We conducted a retrospective and prospective study on 477 renal transplants performed at our hospital from 1980 to 1996. The tumor type, course and possible tumor-related factors (immunosuppression, age, sex, graft rejection, virus) were analyzed., Results: 57 tumors were found; 41 patients had at least one tumor. The most common were skin, renal and lung cancer. Age, sex and immunosuppression were found to be tumor-related factors in renal transplant recipients., Conclusions: Patients undergoing renal transplantation are at a higher risk for developing a tumor, above all in the older male patients. A relationship was found for immunosuppression, the number of drugs received and the number of rejection episodes. Furthermore, the tumor pattern in these patients is different from the usual pattern.

Objective: To determine the neurologic alterations of patients with ejaculatory and orgasmic disorders., Methods: A study of the neuroandrologic profile was performed in eight patients; 6 presented an ejaculation, one premature ejaculation and one presented an orgasm. The neuroandrologic profile consisted in performing selective electromyography of the bulbocavernosus muscle, recording of the S2-S4 evoked potentials, evoked somatosensory potentials of the pudendal nerve, electromyography of the smooth cavernous muscle (SPACE), sympathetic skin response and cystometry., Results: The sympathetic lesion was more frequent in the cases with an ejaculation (four cases; 66%); a pudendal efferent lesion was demonstrated in one case (17%) and a suprasacral lesion in one case (16%). A pudendal afferent lesion was observed in the two cases with premature ejaculation (100%). Both cases with an orgasm had a pudendal afferent lesion (100%) and one of them also presented a sympathetic lesion (50%)., Conclusions: An ejaculation appears to be caused by sympathetic, motor pudendal or suprasacral lesion. An altered perception of genital sensations due to lesion of the afferent pudendal pathway appears to be present in premature ejaculation. An orgasm could be ascribed to an alteration of the pudendal sensibility or to the absence of ejaculation.

Objective: To analyze the neurological alterations responsible for impotence in multiple sclerosis., Methods: We conducted a pharmacologic erection test and a neuroandrologic profile study in 11 patients with multiple sclerosis and impotence. This study consisted in: bulbocavernosus EMG, S2-S4 evoked potentials, somatosensory potentials of pudendal nerve, electromyography of cavernous smooth muscle (SPACE), sympathetic skin response (SSR) and cystometry., Results: The most frequent neurological lesion was complete suprasacral (7 cases; 64%) and parasympathetic (7 cases; 64%) lesions. The parasympathetic lesions were of the upper motor neuron type in 6 of the 7 cases (86%). Peripheral autonomic [sympathetic in 2 cases (18%); parasympathetic in 1 case (9%)] and pudendal lesions (3 cases; 27%) were also observed., Conclusions: The main cause of impotence in multiple sclerosis could be ascribed to a suprasacral lesion. Some cases also present peripheral autonomic lesions.

Objective: To analyze the pathological and clinical features of a variant of renal carcinoma: sarcomatoid renal carcinoma., Methods: Of 316 patients diagnosed as having a renal tumor from 1975 to 1995, 11 (3.5%) with a pathological diagnosis of sarcomatoid renal carcinoma were analyzed. The clinical history, biological data and diagnostic imaging findings of these patients were reviewed. All patients had undergone surgical exploration., Results: All the tumors showed a double cellular population, with a fusiform component. Histological analysis showed a high grade and stage tumor. Ten patients died from the disease, the mean survival rate was 9 months (range 2-48) following diagnosis., Conclusions: Sarcomatoid carcinoma of the kidney is uncommon and can be occasionally difficult to distinguish from sarcoma. It has a worse prognosis than other variants of renal carcinoma.

Objective: To determine the utility of the urethral plug in the management of female stress urinary incontinence., Methods: A prospective clinical study was conducted in 20 female patients with stress urinary incontinence in order to evaluate the efficacy of a new urethral plug. The mean age was 59.6 +/- 6.2 years (range 40-66). The study design included 3 visits (4 weeks). The results were considered "positive" when urinary incontinence decreased and the patient referred a subjective sensation of improvement, and "negative" if otherwise., Results: Positive results were demonstrated in 8 patients (40%). Ten patients (50%) refused to continue, mainly due to urinary tract infection in 7 cases (35%), difficulties in plug use (loss of plugs, anomalous urethral anatomy, cystocele,...) in 6 cases (30%) and urethral mucosa irritation in one case (5%). No plug migrated into the bladder. The initial urinary incontinence grade in the positive cases were: minor in 4 (50%), mild in 2 (25%) and severe in 2 (25%). We found no statistical relationship between the urinary incontinence grade and clinical results. The patients used a median of 5 plugs per day. Of the 10 patients who completed the study, 5 (50%) refused to continue using the plug and 5 (50%) decided to continue using the plug in combination with electrostimulation and/or pelvic floor exercises., Conclusions: The use of the urethral plug in the management of female stress urinary incontinence is not an alternative to surgical treatment or pelvic floor rehabilitation. However, it could be useful for patients who are unwilling or unfit for surgery. Finally, the urethral plug is an alternative to the use of collecting systems or devices in female stress urinary incontinence.

Objectives: To determine the type and to quantify the DURR phenomena in the male., Methods: We conducted a clinical and urodynamic study in 31 male patients with functional lower urinary tract symptoms., Results: DURR is produced by two types of mechanisms: urethral rigidity and contraction of the urethral wall. The patients with DURR produced by rigidity showed a higher score for irritative urinary symptoms. The patient with DURR produced by the contraction of the urethral wall had greater urodynamic consequences (increased opening pressure and PURR curve). The obstructive urinary symptoms were more intense when the DURR presented in the second phase of voiding (after reaching the maximum flow)., Conclusions: The DURR phenomena have clinical and urodynamic consequences in males with functional lower urinary tract symptoms; therefore their type and quantity should be adequately determined.

Objective: To analyze the utility of electromyographic study of the bulbocavernosus muscle., Methods: 126 impotent patients were evaluated by physical examination and neuroandrologic profile. The physical examination consisted in an exploration of the anal tone and the bulbocavernosus reflex. The neuroandrologic profile consisted in selective electromyography of the bulbocavernosus muscle, the determination of the S2-S4 evoked potentials, somatosensory potential of the pudenal nerve, electromyography of cavernous smooth muscle (SPACE) sympathetic skin response and cystometry., Results: The results of the bulbocavernosus electromyography and S2-S4 evoked potentials were different from the data obtained from the physical examination of the anal tone and the bulbocavernosus reflex. Selective bulbocavernosus electromyography showed a sensitivity of 57% and a specificity of 84%. The S2-S4 evoked potentials showed a sensitivity of 61% and a specificity of 100%. The diagnostic value of the S2-S4 evoked potentials increased at 39 msec cutoff (sensitivity = 66%; specificity = 95%). Exploration of the anal tone is very specific for neurologic lesion in impotence (93%), but has a low sensitivity (30%). The clinical bulbocavernosus reflex showed a good specificity (85%) and sensitivity (75%) in the diagnosis of pudendal efferent lesion, but is less useful in the diagnosis of neurogenic impotence., Conclusions: The highest diagnostic value was obtained with the S2-S4 evoked potentials. Selective electromyography of the bulbocavernosus muscle showed a moderate diagnostic value. Physical examination of peripheral pudendal innervation does not appear to be useful for screening for neurologic lesion in impotence because of its low sensitivity, which may be due to existing incomplete nervous lesions.

Objective: To analyze the clinical and urodynamic efficacy of treatment with doxazosin during 6 months for voiding phase disorders in patients with BPH., Methods: A prospective clinical and urodynamic study (before and after treatment) was performed in 65 consecutive male patients with BPH, aged 54-79 years (mean 66.7), to evaluate the results of treatment with doxazosin 4 mg/day during 6 months. Clinical evaluation included patient history and the International Prostatic Symptom Score (IPSS) and urodynamic evaluation included uroflowmetry with post-void residual data and pressure-flow test. A static urethral pressure profile was associated with the urodynamic voiding study., Results: The IPSS score improved significantly from 19.8 +/- 4.8 before treatment to 11.9 +/- 4.6 after treatment (p < 0.001). Urinary symptoms improved significantly more markedly after treatment (coeff. -0.45939) in patients with a lower IPSS score. The symptomatic improvement demonstrated by the IPSS did not correlate with the DRE or the transabdominal US prostatic volume. Mean maximum flow rate before treatment was 9.13 ml/sec and increased to 16.23 ml/sec after treatment (p < 0.01). Postvoid residual dropped from 21.7% to 12.5% (p < 0.01). In the pressure-flow test, foot-point PURR dropped significantly from 69 cms H2O to 45.9 cms H2O (p < 0.001). The PURR curvature diminished from 0.27416 to 0.15964 cms H2O (ml/sec2) (p < 0.01). A statistically significant improvement of the compressive (p < 0.001) and constrictive (p < 0.05) elements of lower urinary tract obstruction was observed. The urethral functional length of the urethral profile showed a significant reduction (pre-treatment: 5.56 cms; post-treatment 4.31 cms) (p < 0.05). A statistical correlation was found between the urethral functional length and the foot-point PURR post-treatment., Conclusions: Adrenergic blockade with doxazosin reduces both the compressive and constrictive elements of lower urinary tract obstruction in the voiding phase in patients with BPH, although no statistical correlation with the IPSS could be demonstrated.

Objective: To analyze the clinical and urodynamic efficacy of treatment with doxazosin during 6 months for bladder filling phase disorders in patients with BPH., Methods: A prospective clinical and urodynamic study was performed in 65 males with BPH, aged 54-79 years (mean 66.7), who had been treated with doxazosin (4 mg/day) during 6 months. Clinical [International Prostatic Symptom Score (IPSS)] and urodynamic evaluations (cystometry and filling cystography) before and after treatment were performed. IPSS data were obtained according to the WHO recommendation following validation and translation into Spanish., Results: The IPSS score improved significantly from 19.8 +/- 4.8 before treatment to 11.9 +/- 4.6 after treatment (p < 0.001). All the patients were normotensive before and after treatment (systolic and diastolic blood pressures 135.9/78.9 and 135.4/77.8 mmHg, respectively). No tachycardia was observed before (71.9 +/- 5.8) or after treatment (71.8 +/- 5.9). A relationship between the lower IPSS before treatment and urinary symptoms improvement was demonstrated (coef.-0.45939). We found no relationship between prostate volume (digital rectal examination or transabdominal ultrasonography) and IPSS modifications after treatment. Bladder instability decreased significantly from 71.6% before treatment to 33.3% after treatment (p < 0.01). Instability pressure also diminished from 99.2 cms H2O to 60.3 cms H2O after doxazosin treatment (p < 0.001). We found no significant relationship between IPSS and bladder instability post-treatment., Conclusions: Adrenergic blockade with doxazosin 4 mg/day for 6 months achieves a significant decrease in the bladder instability associated with prostatic obstruction in patients with BPH, although no statistical correlation with the IPSS could be demonstrated.

Objective: The present study was conducted to determine the changes in the neuro-andrologic profile of patients with impotence following rectal ablative surgery., Methods/results: The study comprised 18 patients who had undergone rectal surgery: abdominoperineal resection of the rectum (AP) in 12 cases (67%), anterior resection of the rectum (AR) in 6 cases (33%). The pharmacologic erection test was negative in 60% of the patients (56% of the AP cases and 67% of the RA cases; differences not significant). Sympathetic lesion was demonstrated in 67% of the patients (50% of the AP cases and 100% of the AR cases; significant difference). Parasympathetic lesion was demonstrated in 38% of the patients (56% of the AP and in none of the RA cases; tendency towards statistical significance). Pudendal lesion was demonstrated in 83% of the patients, although no significant differences concerning pudendal involvement were observed between both types of surgery (92% of the AP group and 67% of the RA group). The frequency of the pudendal lesion was significantly greater than the parasympathetic lesion and the sympathetic lesion tended to be significantly greater than the parasympathetic lesion in patients undergoing ablative rectal surgery. No significant differences were observed between the pudendal and the sympathetic lesion in these patients. No relationship was observed between the type of neurologic lesion and the results of the pharmacologic erection test., Conclusions: The type of neurological lesion appears to be related with the level of the rectal surgery. The sympathetic innervation would be more frequently compromised in anterior resection of the rectum. The parasympathetic innervation would be more frequently compromised in abdominoperineal resection. The pudendal innervation would be affected by both types of surgical techniques.

Objectives: To evaluate the clinical and urodynamic data of a multicenter study on female urinary stress incontinence undergoing surgical repair with the Ramírez simplified urethropexy., Methods: Clinical, urodynamic and videocystographic data were analyzed in a multicenter series of 340 female patients with urinary stress incontinence (mean age 51.7 +/- 9.7 years) before and after the Ramírez urethropexy technique (mean follow-up 21.7 months)., Results: Post surgical urinary continence was 78.4%. Cystocele repair was demonstrated in 57.7%. Urge incontinence decreased in 17.1%. Daytime frequency statistically significantly decreased in 19%. Urinary obstructive symptoms increased in 19.3%. Bladder instability significantly decreased posturethropexy. Peak urinary flow rate and mean urinary flow rate diminished in 65% and 59%, respectively. Postvoiding residual urine increased significantly. No statistical correlation between posturethropexy continence and videocystographic bladder neck morphology was observed., Conclusions: The clinical and urodynamic data obtained in our series indicate that the Ramírez urethropexy technique, a simple and fast procedure, may be considered an alternative treatment in female urinary stress incontinence.

Objective: To determine the relation of the urinary flow curve morphology of free flowmetry with the status of lower urinary tract dynamics., Methods: A mathematical model was designed to fit the urinary flow curves to two models: a symmetrical and an asymmetrical model. Based on these models we analyzed the relationship between the presence or absence of obstruction and the type of model which better adjusted the urinary flow curves in a series of 85 males., Results: The urinary flow curves corresponding to absence of obstruction adjusted significantly better to a symmetrical model than those corresponding to bladder outlet obstruction. No correlation was observed between the type of curve and bladder contractibility or type of urinary obstruction., Conclusions: There is a relationship between the form of the urinary flow curve and bladder obstruction. In the absence of obstruction, the urinary flow curves are more symmetrical.