Kidney Calculi, Urinary Lithiasis, Urolithiasis
Conditions
Keywords
Tomography, Urinary Lithiasis, Kidney Calculi
Brief summary
Kidney stone disease affects almost 10% of overall population, often requiring a surgical intervention. Currently, shock wave lithotripsy is considered a first-line treatment option for patients suffering from symptomatic kidney stones smaller than 2.0 cm, providing reasonable stone-free rate. Actually, the outcomes from SWL vary largely due to several factors including stone burden, stone density, stone-skin distance (SSD), and patient's body habitus. Furthermore, the imaging exam modality (i.e. ultrasound versus computed tomography scan) performed to assess the presence of residual fragments also impacts on SWL outcome analysis. We aim to perform a well-controlled prospective evaluation of all variables that may impact on fragmentation and clearance of lower pole calculi after SWL. These variables are assessed exclusively by a noncontrast computed tomography scan (NCCT), eliminating the necessity of an intravenous urography to study renal collecting system anatomy; an imaging exam that is not routinely performed anymore for kidney stone patients.
Detailed description
Variables in study: * Age, gender, body mass index (BMI), and waist abdominal circumference * Noncontrast computed tomography scan (NCCT): stone density (average of 3 measurements), stone size, stone area, skin to stone distance (average of 3 measurements: zero, 45o and 90o), and collecting system anatomy: infundibular length, width, and height, and infundibulopelvic angle Study design: All patients will be submitted to a noncontrast computed tomography scan before to SWL. A radiologist with expertise in urolithiasis will evaluate all exams. Patients will be submitted to SWL under the following conditions: outpatient, general anesthesia, 3000 impulses, rate of 90/min, discharged from hospital in the same day with alpha-blocker (doxazosin) during 30 days. Patients will be followed up as follow: * One week after SWL: medical visit To evaluate complications such as pain, dysuria, hematuria, steinstrasse, visit to the emergency department. * 12 weeks after SWL: new NCCT scan To evaluate kidney stones fragmentation and clearance. Univariate (Student's T test) and multivariate analysis (multiple logistic regression) will be done to assess the impact of patient's corporal habitus (BMI and abdominal waist circumference), stone characteristics (size, area, density and SSD), and renal collecting system anatomy (infundibular length, width and height, and infundibulopelvic angle) on SWL outcomes (fragmentation and stone-free rates).
Interventions
DEVICESWL - Compact Delta Dornier Med Tech
All patients will be submitted to a noncontrast computed tomography before to SWL. Patients will be submitted to SWL under the following conditions: outpatient, general anesthesia, 3000 impulses, rate of 90/min, discharged from hospital in the same day with alpha-blocker (doxazosin) during 30 days.
Sponsors
University of Sao Paulo
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
\> 17 year-old. Symptomatic single stone of 5 to 20mm located in the lower pole of the kidney. Informed consent signed.
Exclusion criteria
Patients with congenital kidney abnormalities (i.e. horseshoes kidney, pelvic kidney, ectopic kidney), patients with ureteral stent (i.e. Double J stent) in the ipsilateral kidney of the stone in study, patients with chronic kidney disease (glomerular filtration rate \<60 mL/minute/1.73m2 measured by the equation Modification of Diet in Renal Disease), and patients with absolute contraindication to SWL (i.e. coagulopathy, pregnancy, urinary tract infection, or abdominal aneurysm \>4.0cm).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Stone Clearance | 12 weeks after SWL | After 12 weeks, all patients will be submitted to a new NCCT scan to evaluate stone fragmentation and stone clearance. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| SWL Complications | 12 weeks after SWL | Secondary endpoint will be SWL complications (i.e. pain, hematuria, urinary tract infection, Steinstrasse) |
Countries
Brazil
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Shockwave Lithotripsy (SWL) One hundred patients fulfilled the inclusion and exclusion criteria and were enrolled in this study. Mean age and BMI were 47.1 years and 28.0 Kg/m2, respectively. Half of patients had their stone localized in the right kidney. Mean stone size was 9.1mm and mean stone density was 795 HU. | 100 |
| Total | 100 |
Baseline characteristics
| Characteristic | Shockwave Lithotripsy (SWL) |
|---|---|
| Age, Continuous | 47.1 years STANDARD_DEVIATION 12.5 |
| BMI | 28.0 Kg/m2 STANDARD_DEVIATION 4.7 |
| Region of Enrollment Brazil | 100 participants |
| Sex: Female, Male Female | 50 Participants |
| Sex: Female, Male Male | 50 Participants |
| Waist abdominal circumference | 94.1 cm STANDARD_DEVIATION 12.7 |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 104 |
| serious Total, serious adverse events | 0 / 104 |
Outcome results
Primary
Stone Clearance
After 12 weeks, all patients will be submitted to a new NCCT scan to evaluate stone fragmentation and stone clearance.
Time frame: 12 weeks after SWL
Population: Fragmentation
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Primary Endoint | Stone Clearance | 76 participants |
Secondary
SWL Complications
Secondary endpoint will be SWL complications (i.e. pain, hematuria, urinary tract infection, Steinstrasse)
Time frame: 12 weeks after SWL
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Primary Endoint | SWL Complications | 7 participants |