Factores de riesgo preoperatorios en pacientes con pielonefritis xantogranulomatosa sometidos a nefrectomía.

OBJETIVO: Identificar factores de riesgo asociados a complicaciones mayores en pacientes con pielonefritis xantogranulomatosa sometidos a nefrectomía. MÉTODO: Análisis retrospectivo de expedientes clínicos de pacientes con pielonefritis xantogranulomatosa sometidos a nefrectomía. Se analizaron el sexo, el índice de masa corporal, el índice de comorbilidad de Charlson, la clasificación del estado físico de la American Society of Anesthesiologists, la etapa de Malek, el conteo leucocitario y los valores de creatinina. Las complicaciones se estratificaron en menores y mayores según la clasificación de Clavien-Dindo. Se realizó análisis univariado y bivariado usando las pruebas exacta de Fisher y ji al cuadrado de Pearson, y se establecieron medidas de riesgo utilizando la odds ratio (OR). RESULTADOS: Se analizaron 72 pacientes con una edad media de 50 años, el 83% mujeres, el 58.3% con urocultivo positivo y el 66% con litiasis renal. El 32% tuvieron alguna complicación mayor y el 15% requirieron admisión a la unidad de cuidados intensivos. Los valores elevados de creatinina (OR: 3.8; intervalo de confianza del 95% [IC95%]: 1.1-13; p = 0.02) y la etapa Malek II-III (OR: 4.5; IC95%: 1.2-17.5; p = 0.02) se asociaron con complicaciones mayores. CONCLUSIÓN: El estadio de Malek y los valores elevados de creatinina incrementan el riesgo de desarrollar complicaciones mayores en los pacientes con pielonefritis xantogranulomatosa sometidos a nefrectomía. OBJECTIVE: To identify preoperative risk factors associated with major complications in patients with xanthogranulomatous pyelonephritis undergoing total nephrectomy. METHOD: Retrospective analysis of patient's charts with xanthogranulomatous pyelonephritis who underwent nephrectomy. Risk factors included for analysis were gender, body mass index, Charlson comorbidity index, American Society of Anesthesiologists physical status classification, Malek's stage, leukocyte count and creatinine levels. Postoperative complications were stratified in minor and major according to Clavien-Dindo's classification. Univariate and bivariate analysis using Fisher's exact test, Pearson's chi-squared and odds ratio (OR) was performed. RESULTS: 72 patients were analyzed, 83% women, mean age of 50 years, 58.3% positive urine cultures and 66% kidney stones. Major complications were present in 32% of cases, and 15% were admitted to the intensive care unit. Elevated creatinine (OR: 3.8; 95% confidence interval [95%CI]: 1.1-13; p = 0.02) and Malek's stage II to III (OR: 4.5; 95%CI: 1.2-17.5; p = 0.02) were associated with major complications. CONCLUSION: The Malek Stage and elevated creatinine increases the risk of major complications in patients undergoing nephrectomy due to xanthogranulomatous pyelonephritis.

Factores predictores del estado libre de cálculos en la primera ureteroscopia flexible con litotricia láser.

INTRODUCTION: Flexible ureteroscopy and laser fragmentation (FURSL) is a minimally invasive modality for surgical treatment of renal stones. Inadequate selection of patients for this treatment generates a cost-effectiveness unbalance. OBJECTIVE: To know the stone-free rate predictors in a single surgical time in patients undergoing FURSL. METHOD: Retrospective cohort of patients undergoing FURSL. Global and gender-categorized univariate and multivariate (logistic regression) analyses were performed to identify stone-free predictors at first FURSL. RESULTS: Stone-free rate at first FURSL was 73.62%. Predictors in males were patient age and stone size, density and multiplicity; in females, body mass index and multiplicity of stones. CONCLUSIONS: Stone-free rate predictors at first FURSL are different in males and females. Women with overweight and obesity probably have easy-to-fragment and easy-to-extract stones associated with uric acid.

INTRODUCCIÓN: La ureteroscopia flexible con litotricia láser (URSLL) es una modalidad mínimamente invasiva de tratamiento quirúrgico de cálculos renales. La selección inadecuada de pacientes para este procedimiento genera un desbalance de costo-efectividad. OBJETIVO: Conocer los factores predictores de estado libre de litos en un solo tiempo quirúrgico en pacientes sometidos a URSLL. MÉTODO: Cohorte retrospectiva de pacientes sometidos a URSLL. Se realizó un análisis univariado y multivariado (regresión logística) de los predictores de estado libre de cálculos en la primera URSLL, global y categorizado por sexo. RESULTADOS: EL estado libre de cálculos en la primera URSLL fue de 73.62 %. Los predictores de estado libre de cálculos en hombres fueron edad y tamaño, densidad y multiplicidad del cálculo; en las mujeres, el índice de masa corporal y la multiplicidad del cálculo. CONCLUSIONES: Los factores pronósticos de estado libre de cálculos en la primera URSLL son distintos en hombres y mujeres. Las mujeres con obesidad y sobrepeso probablemente tengan cálculos de fácil fragmentación y extracción asociados con ácido úrico.

Factores predictores del estado libre de cálculos en la primera ureteroscopia flexible con litotricia láser / Predictors of stone-free status in the first flexible ureteroscopy with laser lithotripsy

Resumen Introducción: La ureteroscopia flexible con litotricia láser (URSLL) es una modalidad mínimamente invasiva de tratamiento quirúrgico de cálculos renales. La selección inadecuada de pacientes para este procedimiento genera un desbalance de costo-efectividad. Objetivo: Conocer los factores predictores de estado libre de litos en un solo tiempo quirúrgico en pacientes sometidos a URSLL. Método: Cohorte retrospectiva de pacientes sometidos a URSLL. Se realizó un análisis univariado y multivariado (regresión logística) de los predictores de estado libre de cálculos en la primera URSLL, global y categorizado por sexo. Resultados: EL estado libre de cálculos en la primera URSLL fue de 73.62 %. Los predictores de estado libre de cálculos en hombres fueron edad y tamaño, densidad y multiplicidad del cálculo; en las mujeres, el índice de masa corporal y la multiplicidad del cálculo. Conclusiones: Los factores pronósticos de estado libre de cálculos en la primera URSLL son distintos en hombres y mujeres. Las mujeres con obesidad y sobrepeso probablemente tengan cálculos de fácil fragmentación y extracción asociados con ácido úrico.

Abstract Introduction: Flexible ureteroscopy and laser fragmentation (FURSL) is a minimally invasive modality for surgical treatment of renal stones. Inadequate selection of patients for this treatment generates a cost-effectiveness unbalance. Objective: To know the stone-free rate predictors in a single surgical time in patients undergoing FURSL. Method: Retrospective cohort of patients undergoing FURSL. Global and gender-categorized univariate and multivariate (logistic regression) analyses were performed to identify stone-free predictors at first FURSL. Results: Stone-free rate at first FURSL was 73.62%. Predictors in males were patient age and stone size, density and multiplicity; in females, body mass index and multiplicity of stones. Conclusions: Stone-free rate predictors at first FURSL are different in males and females. Women with overweight and obesity probably have easy-to-fragment and easy-to-extract stones associated with uric acid.

Tasa libre de litos sin complicación mayor como definición de éxito en nefrolitotomía percutánea / Stone-free rate without major complication as a definition of success in percutaneous nephrolithotomy

Resumen Introducción: El éxito en nefrolitotomía percutánea (NLP) se define como estatus libre de litos, sin embargo, las complicaciones mayores se presentan con alta frecuencia y han sido reportadas como resultado secundario. Objetivo: Presentar una nueva definición de éxito en NLP que comprenda la tasa libre de litos sin complicaciones mayores y una escala de riesgo para predecir este desenlace. Método: Cohorte histórica de pacientes sometidos a NLP. Las variables incluidas fueron edad, sexo, urocultivo, índice de comorbilidad de Charlson (ICC) y lito complejo. Se definió éxito: sin litos, sin o con complicación Clavien ≤ 2; éxito intermedio: con litos sin o con complicación Clavien ≤ 2; fracaso: con o sin litos con complicación Clavien > 2. Se realizó análisis bivariado para identificar los factores asociados con el desenlace. Por regresión logística múltiple se calculó el peso independiente de cada factor. Resultados: Se incluyeron 568 procedimientos, 59 % en el sexo femenino. La mediana de edad fue de 49 años; 65, 22 y 13 % de los casos tuvieron éxito, éxito intermedio y fracaso. El sexo femenino, urocultivo positivo, lito complejo e ICC severo se asociaron con fracaso. Conclusión: La probabilidad de éxito fue directamente proporcional al número de factores de riesgo.

Abstract Introduction: Success in percutaneous nephrolithotomy (PCNL) is defined as a stone-free status; however, major complications are highly common and have been reported as a secondary outcome. Objective: To propose a new definition of PCNL success that comprises a stone free rate without major complications and a risk scale to predict this outcome. Methods: Historical cohort of patients undergoing PCNL. The included variables were age, gender, urine culture, Charlson's comorbidity index (CCI) and complex stones. Success was defined as a stone free status with or without Clavien grade ≤ 2 complication; intermediate success: with stones, with or without Clavien grade ≤ 2 complication; and failure: with or without stones with Clavien grade ≤ 2 complication. Bivariate analysis was performed to identify which factors are associated with the outcome. The independent weight of each factor was calculated by multiple logistic regression analysis. Results: 568 procedures were included, 59% of which were in females. Median age was 49 years; 65%, 22% and 13% of cases were classified as success, intermediate success and failure, respectively. Female sex, positive urine culture, complex stones and severe CCI were associated with failure. Conclusions: The likelihood of success was directly proportional to the number of risk factors.

[Intrarectal povidone-iodine to reduce the risk of genitourinary infections after transrectal prostate biopsy]. / Iodopovidona intrarrectal y riesgo de infección genito- urinaria posterior a biopsia prostática transrectal.

BACKGROUND: The aim of this study is to compare two different preparations in patients undergoing transrectal prostate biopsies samples (TPBS) and assess the prevalence of genitourinary infections (GUI). METHODS: A historical cohort of patients undergoing TBPS for suspected prostate cancer. Two groups were compared: one with endorectal lubricant jelly and another with the addition of a povidone-iodine lubricating jelly. Complications were evaluated at three weeks. A bivariate analysis was performed by calculating the OR (95 % CI) to determine if the additional endorectal povidone-iodine pre-TBPS reduced GUI and other complications. RESULTS: 185 patients (Group I n = 86, Group II n = 96) were evaluated. 45 and 25 % had genitourinary tract infection (OR: 0.4, CI: 0.2-0.9, p = 0.004); fever was presented in 21 and 10 % respectively (OR: 0.42, CI: 0.1-0.9, p = 0.04). CONCLUSIONS: A reduction was observed in the presence of genitourinary infections in patients who had intrarectal povidone-iodine preparation applied.

Introducción: el objetivo de este estudio es comparar dos preparaciones distintas en pacientes sometidos a la toma de biopsias prostáticas transrectales (BPTR) y evaluar la prevalencia de infecciones genitourinarias (IGU). Métodos: se compararon dos grupos de pacientes con sospecha de cáncer de próstata sometidos a Biopsia Prostática Transrectal (BPTR): Con jalea lubricante endorrectal (grupo l, cohorte histórica) y con jalea lubricante más iodopovidona (grupo II, cohorte prospectiva). Se evaluaron las complicaciones a las tres semanas. Se realizó un análisis bivariado, calculando su OR (IC: 95 %) para determinar si la iodopovidona endorrectal adicional previa a la BPTR disminuye las IGU y otras complicaciones. Resultados: Se evaluaron 185 pacientes (Grupo I n = 86; grupo II n = 96). Tuvieron infección del tracto genitourinario el 45 y 25 % (OR: 0.4, IC: 0.2-0.9, p = 0.004); la fiebre se presentó en el 21 y 10 % respectivamente (OR: 0.42, IC: 0.1-0.9, p = 0.04). Conclusiones: Se observó una reducción en la presencia de infecciones genitourinarias en pacientes a quienes se aplicó en su preparación iodopovidona intrarrectal.

[Urachus cystopexy: new technique for bladder suspension associated to the Burch's technique in the treatment of cystocele and stress urinary incontinence. Long-term follow-up]. / Uraco-cistopexia: nueva técnica de cisto-suspensión asociada al Burch para el tratamiento del cistocele e incontinencia urinaria de esfuerzo, seguimiento a largo plazo.

OBJECTIVES: To compare long term efficacy and morbidity in patients with stress urinary incontinence treated using Burch's colpopexy versus Burch's colpopexy plus urachus-cystopexy. METHODS: Retrospective, longitudinal comparative, observational study in 129 patients with stress urinary incontinence (SUI) or mixed urinary incontinence (MUI). Fifty four patients underwent Burch's colpopexy (group B) and 75 patients underwent Burch's colpopexy and urachus-cystopexy (group B U). These patients completed inclusion criteria from January 1994 to March 2005. The severity of SUI was evaluated by means of the number of pads used in 24 hours. Cure was defined as patients not using any pad for urinary leakage; improvement, when the number of pads used decreased to one pad a day; and failure when the patients used more than 1 pad in 24 hours. In MUI the urge urinary incontinence (UUI) component was evaluated separately. RESULTS: After 12 months of follow-up, 47 patients of group B and 67 patients of group BU were evaluated analyzing cure/improvement. Either one were observed in 74.4% (29/6) and 97% (58/7) respectively (p = 0.001). At 24 months follow up, in 35 patients of group B and 42 of group BU, a rate of 65.7% (22/3) and 97.6% (37/4) was observed respectively (p = 0.014). MUI was present in 53.7% of group B and 58.6% patients of group BU. An independent analysis was made on urge urinary incontinence (UUI) in these patients at 12 months; 53.1% of group B and 19.4% of group BU had UUI (p = 0.000). At 24 months, 50% of patients of group B and 26.19% of group BU had UUI (p = 0.029). De novo UUI was present in 19.4% of group B and 5.97% of group BU (p = 0.000) at 12 months follow-up, and in 17.64% of patients of group B and 13.95% of group BU (p = 0.005) at 24 months. Complications related to urachus-cystopexy presented trans-operatively: vesical injury in 3 of the initial cases, solved with bladder closure in two layers and vesical catheter for 7 days approximately. CONCLUSIONS: Burch's procedure in addition to urachus-cystopexy was better for the treatment of SUI and UUI than Burch's procedure alone in a long term clinical follow-up. Surgical fixation of the urachus to the anterior abdominal wall provides extra support to the bladder and probably reduces its displacement during strength, avoiding tension of urethral and bladder neck fixations and increasing the efficacy of Burch's procedure.

Alcances de una estrategia educativa desde una perspectiva participativa de la educación en el desarrollo de lectura crítica de informes de investigación en médicos residentes de medicina nuclear / Developing critical skills to analyze research reports in nuclear medicine

Objetivo: Estimar los alcances de una estrategia educativa en el desarrollo de la lectura crítica de informes de investigación en médicos residentes de medicina nuclear. Métodos: Estudio de intervención entre mayo y junio de 2007 para medir el grado de desarrollo de lectura crítica en médicos residentes de medicina nuclear. Se elaboró un instrumento con cinco resúmenes de informes de investigación en medicina nuclear, con 96 enunciados que exploraron cuatro indicadores (interpretar, enjuiciar, proponer y valoración de aspectos técnicos y tecnológicos). Se estimó la confiabilidad interna con la prueba de Kuder-Richardson 20 (0.89). Se conformaron cinco categorías: muy bajo (17-32), bajo (33-48), medio (49-64), alto (65-80) y muy alto (81-96). El análisis estadístico se realizó con estadística no paramétrica. Resultados: Al inicio de la estrategia, 80 % de los residentes mostró un grado de dominio de lectura crítica muy bajo e incluso calificaciones dentro de lo explicable por efecto del azar; al final de la misma, 90% alcanzó un dominio medio. Las diferencias fueron estadísticamente significativas (p=0.02). Conclusiones: La estrategia educativa propició un avance en el desarrollo de lectura crítica de informes de investigación en medicina nuclear.

OBJECTIVE: To estimate the impact of an educational strategy aimed at developing critical reading of research reports among medical residents enrolled in a nuclear medicine course. METHODS: We carried out an intervention study to measure the degree to which students developed critical reading skills in a one month period (May-June, 2007). We developed an instrument that included five summaries of research articles in nuclear medicine and 96 sentences that measured four indicators (interpret, judge, propose, and assessment of technical and technological aspects). The instrument's internal validity was measured using the Kuder-Richardson test (KR 20 = 0.89) stratified in five scores: very low (17-32), low (33-48), medium (49-64), high (65-80) and very high (81-96). Non-paramentric statistics was employed to determine significant differences. RESULTS: At the beginning of the intervention, 0.80 of participating residents scored in the [quot ]very low[quot ] domain of critical reading even after controlling for a random effect. At the end of the study, 0.90 scored in the [quot ]medium[quot ] category. Results were statistically significant (p = 0.02). CONCLUSIONS: The educational strategy tested, fostered the development of critical reading skills among a sample of nuclear medicine residents.

[Two methods for transrectal ultrasound-guided biopsy of the prostate: systematic vs. guided for suspect echogenic lesion]. / Dos métodos para la toma de biopsia transrectal de próstata ecodirigida: sistemática versus ecosospechosa.

OBJECTIVE: We undertook this study to determine the efficiency of ultrasound-guided transrectal prostate biopsy applying two techniques: systematic extended vs. suspicious sonographic areas. METHODS: Medical files and histopathological reports were reviewed of patients who were treated at the Specialties Hospital of the 21st Century Medical National Center in Mexico City with suspicion of prostate cancer (T1, T2 and PSA <10 ng/ml). Patients had ultrasound-guided transrectal prostate biopsy applying two techniques: systematic extended vs. hypoechoic suspicious sonographic areas. Studies were carried out from January 1, 2005 to July 2006. RESULTS: Of 145 selected patients submitted to ultrasound-guided transrectal prostate biopsy, systematic extended biopsy (group I) was carried out in 73 (50.3%), taking on average 11.75 cylinders per patient. In 72 (49.6%) patients, biopsies were taken on suspicious sonographic areas (group II), taking on average 4.02 cylinders. In group I, 36 (49.3%) patients were positive vs. group II, where 20 (27.7%) patients were positive (p <0.01) with an estimation of risk in favor of group I, determining a probability 2.5 times higher of positivity with this technique (95% confidence interval: range 1.2-5) and a better performance in 22%. CONCLUSIONS: Systematic extended ultrasound-guided transrectal prostate biopsy represents a technique with a higher rate of efficiency than using ultrasound-guided transrectal prostate biopsy in suspicious sonographic areas and has proven over time to be the superior prostate biopsy technique for diagnosis of prostate cancer. It must be considered the method of choice.

[Perinephric abscess: associated factors and mortality]. / Absceso perirrenal: factores asociados a su desarrollo y mortalidad.

OBJECTIVES: To determine predisposing factors in perinephric abscesses and to find events associated with unfavourable outcome. METHODS: We carried out a clinical, descriptive, retrospective and cross-sectional study, including 23 patients diagnosed of perinephric abscess admitted to our hospital. RESULTS: In patients with perinephric abscess, clinical charts included diabetes mellitus in 65.2%, history of nephrolithiasis in 43.47% and history of urological surgery in 17.38%. On hospital admission, haemoglobin greater than 10.5 g/dL and white blood cell count lower than 15 x 10(3) / microL were associated with nephrectomy, and platelet count lower than 140 x 10(3) / microL with septic shock. General mortality was 8.69%, and 78.3% if patient required nephrectomy. Patients who died had fever, anaemia, white blood cell count greater than 16 x 10(3) / microL, platelet count lower than 130 x 10(3) / microL, and hyponatremia of 125 mEq/L or lower at hospital admittance, and all of them had septic shock and required nephrectomy. CONCLUSIONS: In our series, a higher percentage of patients had diabetes mellitus and/or nephrolithiasis. Haemoglobin level and white blood cells count were associated with loss of the renal unit, thrombocytopenia was associated with septic shock and hyponatremia with mortality.

Dos métodos para la toma de biopsia transrectal de próstata ecodirigida: sistemática versus ecosospechosa / Two methods for transrectal ultrasound-guided biopsy of the prostate: systematic vs guided for suspect echogenic lesion

OBJECTIVE: We undertook this study to determine the efficiency of ultrasound-guided transrectal prostate biopsy applying two techniques: systematic extended vs. suspicious sonographic areas. METHODS: Medical files and histopathological reports were reviewed of patients who were treated at the Specialties Hospital of the 21st Century Medical National Center in Mexico City with suspicion of prostate cancer (T1, T2 and PSA <10 ng/ml). Patients had ultrasound-guided transrectal prostate biopsy applying two techniques: systematic extended vs. hypoechoic suspicious sonographic areas. Studies were carried out from January 1, 2005 to July 2006. RESULTS: Of 145 selected patients submitted to ultrasound-guided transrectal prostate biopsy, systematic extended biopsy (group I) was carried out in 73 (50.3%), taking on average 11.75 cylinders per patient. In 72 (49.6%) patients, biopsies were taken on suspicious sonographic areas (group II), taking on average 4.02 cylinders. In group I, 36 (49.3%) patients were positive vs. group II, where 20 (27.7%) patients were positive (p <0.01) with an estimation of risk in favor of group I, determining a probability 2.5 times higher of positivity with this technique (95% confidence interval: range 1.2-5) and a better performance in 22%. CONCLUSIONS: Systematic extended ultrasound-guided transrectal prostate biopsy represents a technique with a higher rate of efficiency than using ultrasound-guided transrectal prostate biopsy in suspicious sonographic areas and has proven over time to be the superior prostate biopsy technique for diagnosis of prostate cancer. It must be considered the method of choice.

[A case of renal cell carcinoma in horseshoe kidney]. / Carcinoma de células claras en riñón en herradura. Descripción de un caso y revisión de la literatura.

Horseshoe kidney has a frequency of 1 in 1000 renal paiss. Diseases in this type of kidneys have anatomical particularities that should be taken into account during surgery. We present the case of a renal cell carcinoma in this type of renal fusion.

Carcinoma de células claras en riñón en herradura: Descripción de un caso y revisión de la literatura / A case of renal cell carcinoma in horseshoe kidney

El riñón en herradura se encuentra en uno de cada 1000 pares renales y la patología en estos riñones suele tener características anatómicas especiales que se deben tener en consideración para su abordaje quirúrgico. Presentamos el caso de un carcinoma de células claras en este tipo de fusión renal.

Horseshoe kidney has a frequency of 1 in 1000 renal paiss. Diseases in this type of kidneys have anatomical particularities that should be taken into account during surgery. We present the case of a renal cell carcinoma in this type of renal fusion.