[Renal lithiasis, can we predict the need for retreatment in retrograde intrarenal surgery (RIRS)?] / Litiasis renales, ?podemos predecir la necesidad de retratamientos en cirugía retrógrada intrarrenal?.

OBJECTIVES: To analyze the predictive factors for retreatment in RIRS to achieve complete lithiasis resolution. METHODS: Retrospective comparative study analyzing 298 cases of RIRS performed in our center over a 3 year period. The cohort was divided in two groups: Resolution in one operation or more than one, evaluating homogeneicity for age and gender. We compared the folowing variables: Hounsfield units, body mass index (BMI), number of stones, size, (on the case of multiple stones, larger stone size), side, location in the kidney and stone biochemistry. Bivariant statistical analysis by Student's t and Chi square tests, and multivariate analysis by binary logistic regression. ROC curves were made to set cutting points for relationship between quantitative variables. RESULTS: The groups were homogeneous for both age and gender (p>0.05). 260 (87.25%) patients required one treatment only and 38 (12.75%) more than one. Among the study variables, the only one that showed differences between the groups wa stone size, being the mean size 18 mm in the single treatment group and 26 mm in the more than one treatment group (Difference between mean values -8.27, 95%CI: -5,91 - -10.63, p<0,001). CONCLUSIONS: RIRS with holmium laser is still an effective technique for the treatment of renal lithiasis. The largest stone size is related with the need of retreatments, so it must be taken into consideration specially over 2 cm. In our series, for every extra millimeter in size the probability of retreatment increased 1.14 times, demonstrating the importance of size in this context.

Litiasis renales, ¿Podemos predecir la necesidad de retratamientos en cirugía retrógrada intrarrenal? / Renal lithiasis, can we predict the need for retreatment in retrograde intrarenal surgery (RIRS)?

OBJETIVO: El objetivo de este trabajo fue analizar los factores predictivos de retratamientos para la resolución completa de la litiasis mediante cirugía retrógrada intrarrenal (CRIR). MÉTODOS: Estudio retrospectivo y analítico comparativo sobre 298 casos de CRIR realizados en nuestro centro a lo largo de 3 años. Se dividió a la muestra en dos grupos: resolución con una cirugía, o con más de una, estudiándose la homogeneidad para edad y sexo. Se compararon las siguientes variables pre e intraoperatorias entre cada grupo: Unidades Hounsfield (UHC), Índice de masa corporal (IMC), número de litiasis, tamaño de la litiasis (en caso de múltiples, tamaño mayor de la litiasis más grande), lateralidad, localización dentro del riñón, y bioquímica de la litiasis. Análisis estadístico bivariante mediante T-Student y chi-cuadrado, y multivariante mediante regresión logística binaria. Se realizaron curvas ROC para establecer puntos de corte en caso de relación con variables cuantitativas. RESULTADOS: Grupos homogéneos para edad y sexo (p > 0,05), 260 (87,25%) sujetos precisaron un solo tratamiento y 38 (12,75%) más de uno. Dentro de las variables estudiadas, la única con diferencias entre los dos grupos fue el tamaño de la litiasis, siendo la media en el grupo de un tratamiento de 18 mm, y de 26 mm en el de más de un tratamiento (diferencia de medias -8,27, IC 95%: -5,91 -- -10,63, p < 0,001). Por cada milímetro más de tamaño, la probabilidad de necesitar más de un tratamiento aumenta 1,14 veces (p < 0,001). En la curva ROC se observó que el punto con mayor sensibilidad y especificidad para el tamaño de la litiasis se estableció en 21mm, con ABC de 0,804 (IC 95%: 0,73 - 0,87, p < 0,001). CONCLUSIONES: La CRIR con láser holmio sigue siendo una técnica eficaz para el tratamiento de la litiasis renal. El tamaño mayor de la litiasis se relaciona con la necesidad de retratamientos, debiendo tenerse en cuenta este hecho sobre todo a partir de los 2 cm. En nuestra serie, por cada milímetro más de tamaño de la litiasis, aumentó 1,14 veces la probabilidad de retratamientos, lo cual demuestra la importancia e influencia del tamaño en este contexto

OBJECTIVES: To analyze the predictive factors for retreatment in RIRS to achieve complete lithiasis resolution. METHODS: Retrospective comparative study analyzing 298 cases of RIRS performed in our center over a 3 year period. The cohort was divided in two groups: Resolution in one operation or more than one, evaluating homogeneicity for age and gender. We compared the folowing variables: Hounsfield units, body mass index (BMI), number of stones, size, (on the case of multiple stones, larger stone size), side, location in the kidney and stone biochemistry. Bivariant statistical analysis by Student`s t and Chi square tests, and multivariate analysis by binary logistic regression. ROC curves were made to set cutting points for relationship between quantitative variables. RESULTS: The groups were homogeneous for both age and gender (p > 0.05). 260 (87.25%) patients required one treatment only and 38 (12.75%) more than one. Among the study variables, the only one that showed differences between the groups wa stone size, being the mean size 18 mm in the single treatment group and 26 mm in the more than one treatment group (Difference between mean values -8.27, 95%CI: -5,91 -- -10.63, p < 0,001). CONCLUSIONS: RIRS with holmium laser is still an effective technique for the treatment of renal lithiasis. The largest stone size is related with the need of retreatments, so it must be taken into consideration specially over 2 cm. In our series, for every extra millimeter in size the probability of retreatment increased 1.14 times, demonstrating the importance of size in this context

[Current results of RIRS and comparison with PCNL.] / Resultados actuales de la CRIR y comparación con NLPC.

OBJECTIVES: The objective of this article is to show the current situation regarding two surgical techniques for the treatment of renal lithiasis, RIRS (Retrograde intrarenal surgery) and PCNL (Percutaneous nephrolithotomy), specially concerning the larger size stones. We perform a literature review on the topic and add the experience with both techniques at our center. Besides, we also analyze the role of RIRS in comparison with the percutaneous techniques in smaller size lithiasis. METHODS: We review the results obtained in the literature and our experience. We offer our opinion in reference to the indications of RIRS in these cases based on such review and our experience. RESULTS/CONCLUSIONS: RIRS is a safe and effective technique, with a similar success rate to PCNL if one assumes the possibility of retreatment in stones >2cm. Its low complication rate, fast postoperative recovery and short hospital stay make this technique a therapeutic alternative to PCNL in this type of patients. Compared with percutaneous techniques less invasive than classical 24 to 30 Ch. accesses (miniperc or microperc), RIRS offers a higher stone free rate. If we also consider that RIRS is associated with shorter hospital stay and lower bleeding risk, even without significant differences in the global complication rate we could consider RIRS as the first line endourological treatment in stones <2cm.

Resultados actuales de la CRIR y comparación con NLPC / Current results of RIRS and comparison with PCNL

OBJETIVO: El objetivo del siguiente trabajo es mostrar la situación actual en lo referente a dos técnicas quirúrgicas para el tratamiento de la litiasis renal, CRIR (Cirugia Retrógrada Intrarrenal) y NLPC (Nefrolitotomía Percutánea), sobre todo en lo referente a litiasis de mayor tamaño. Para ello revisamos la literatura al respecto y añadimos la experiencia de nuestro centro en relación a ambas técnicas. Por otro lado, también se analiza el papel de CRIR frente a técnicas percutáneas en litiasis de menor tamaño. MÉTODOS: Revisión de los resultados descritos en la literatura y la experiencia de nuestro centro. Ofrecemos nuestra opinión en base a esta revisión y experiencia propia, en lo referente a las indicaciones de la CRIR en estos casos. Resultados/conclusiones: La CRIR es una técnica segura y eficaz, con una tasa de éxito similar a NLPC si se asume la posibilidad de retratamiento en litiasis >2cm. Su baja tasa de complicaciones, la rápida recuperación postoperatoria y la corta estancia hospitalaria hacen de esta técnica una alternativa terapéutica a la NLPC en este tipo de pacientes. En comparación con técnicas percutáneas de menor invasividad que los accesos clásicos de 24 ó 30 Ch. (mini o microPERC), la CRIR ofrece una mayor tasa libre de litiasis que estas técnicas. Si además, consideramos que la CRIR se acompaña de menor estancia hospitalaria, riesgo de sangrado, aún sin encontrar diferencias significativas en la tasa de complicaciones globales, podríamos considerar la CRIR como tratamiento endourológico de primera línea en las litiasis < 2 cm

OBJECTIVES: The objective of this article is to show the current situation regarding two surgical techniques for the treatment of renal lithiasis, RIRS (Retrograde intrarenal surgery) and PCNL (Percutaneous nephrolithotomy), specially concerning the larger size stones. We perform a literature review on the topic and add the experience with both techniques at our center. Besides, we also analyze the role of RIRS in comparison with the percutaneous techniques in smaller size lithiasis. METHODS: We review the results obtained in the literature and our experience. We offer our opinion in reference to the indications of RIRS in these cases based on such review and our experience. Results/conclusions: RIRS is a safe and effective technique, with a similar success rate to PCNL if one assumes the possibility of retreatment in stones >2cm. Its low complication rate, fast postoperative recovery and short hospital stay make this technique a therapeutic alternative to PCNL in this type of patients. Compared with percutaneous techniques less invasive than classical 24 to 30 Ch. accesses (miniperc or microperc), RIRS offers a higher stone free rate. If we also consider that RIRS is associated with shorter hospital stay and lower bleeding risk, even without significant differences in the global complication rate we could consider RIRS as the first line endourological treatment in stones < 2 cm

[Renal hemorrhage after ESWL: From small hematoma to renal blowout]. / Hemorragia renal tras LEOC: del pequeño hematoma al estallido renal.

OBJECTIVE: To report two cases of renal hemorrhage after extracorporeal shock wave lithotripsy (ESWL) and their therapeutic management. METHODS: Description of the clinical cases, together with the diagnosis and therapeutic management of these complications. RESULTS: We present two cases of patients with renal hemorrhage after ESWL, which were performed without immediate complications. One of the cases, after detecting an important laceration of the renal parenchyma, needed two embolization sessions for its short-term resolution; however, the patient finally passed away due to the complications derived from hemorrhage. The other case was solved through conservative management. CONCLUSIONS: Even though hemorrhage is an infrequent complication after ESWL, it should be suspected when the patient presents compatible clinical symptoms, since even though most cases are resolved in a conservative manner, on some occasions specific treatments for the hemorrhage are necessary. Old age and the presence of vascular comorbidities seem to be related to a higher risk of hemorrhage after ESWL.