Conservative management of staghorn stones.

INTRODUCTION: Since the seminal works by Singh and Blandy in the 1970s, the management of staghorn stones has almost exclusively involved surgical intervention. In contrast, a more recent study found that conservative management was not as unsafe as previously believed. The present review sought to examine the available literature to understand the implications of a conservative strategy. METHODS: A systematic search of the literature was carried out using MEDLINE®, Embase™ and the Cochrane Central Register of Controlled Trials. All papers looking at management of staghorn calculi were reviewed and studies with a conservative management arm were identified. Outcomes of interest were recurrent or severe urinary tract infections, progressive renal deterioration, dialysis requirements, morbidity and disease specific mortality. Owing to the lack of relevant data, a descriptive review was carried out. RESULTS: Our literature search yielded 10 suitable studies involving a total of 304 patients with staghorn stones managed conservatively. Progressive renal deterioration occurred in 0-100% of cases (mean 27.5%) with a higher rate among bilateral staghorn sufferers (44% vs 9%). Dialysis was required in 9% of patients (20% bilateral, 6% unilateral). The mean rate of severe infection was 8.7% and recurrent urinary tract infections occurred in as high as 50% of cases (80% bilateral, 41% unilateral). Disease specific mortality ranged from 0% to 67% (mean 20.5%). CONCLUSIONS: It appears that conservative management of staghorn calculi is not as unsafe as previously thought and selection of patients with unilateral asymptomatic stones with minimal infection should be considered.

Management of staghorn renal stones.

Staghorn stones are large branching stones that fill part of all of the renal pelvis and renal calyces and they can be complete or partial depending on the level of occupancy of the collecting system. Although kidney stones are commoner in men, staghorn stones are less often reported in men compared to women and they are usually unilateral. Due to the significant morbidity and potential mortality attributed to staghorn stones, prompt assessment and treatment is mandatory. Conversely, conservative treatment has been shown to carry a mortality rate of 28% in 10-year period and 36% risk of developing significant renal impairment. Staghorn stones are, therefore, significant disease entity that should be managed aggressively and effectively. Generally, the gold standard treatment for staghorn stones is surgical with a view to achieve stone-free collecting system and preserve renal function. Percutaneous nephrolithotomy should be the recommended first-line treatment for staghorn stones. Other non-surgical options are usually considered in combination with surgery or as monotherapy only if patients are surgically unfit. The decision for optimal treatment of staghorn stones should be individualized according to the circumstances of the patient involved and in order to do so, a closer look at the advantages and disadvantages of each option is necessary.

Conservative Management of Staghorn Calculi: When Is It Safe?

BACKGROUND: To describe the clinical characteristics, infectious and kidney function patterns, and overall outcomes in a cohort of patients with staghorn calculi treated conservatively. METHODS: Staghorn calculi treated nonoperatively between January 2009 and January 2017 were identified. A retrospective analysis was completed. RESULTS: Twenty-nine patients were identified with a median age of 74 years (interquartile range [IQR] 61-81). Mean follow-up was 24 months. Fifty-nine percent (17/29) had complete staghorn calculi with 6/29 (21%) bilateral. Mean body mass index was 29.4 (IQR 24.8-31.7). Of the 29 patients, 14 were treated conservatively due to comorbidities, 12 refused treatments, and 3 were due to aberrant anatomy. The age-adjusted Charlson Comorbidity Index (CCI) score demonstrated 8 patients in our cohort with a CCI of <3, 11 patients with a CCI of 4 or 5, 7 patients with a CCI of 6 or 7, and 3 patients with a CCI of >8. Overall, kidney function remained stable for 19/29 patients (66%) and the glomerular filtration rate decreased by <10% for 4/29 (14%), by 10%-29% for 2/29 (7%), and >30% for 4/29 patients (14%) over the study period. None of the study patients required hemodialysis. No patients in the cohort developed an abscess, nor were any patients on daily prophylactic antibiotics. There was only one related admission for a complication during the study; this was for pyelonephritis. There were two deaths during the study period. One death was an unrelated cardiac death and the other was from urosepsis; this patient had been noncompliant with follow-up. CONCLUSIONS: Outcomes for patients treated conservatively were reasonable in this select group. There is a need for future prospective studies to show whether conservative treatment of these patients is safe.

Prostatic abscess: a rare complication of staghorn calculi.

A staghorn calculus is a calculus accommodating the majority of a renal calyx extending into the renal pelvis. A conservative approach to its treatment may lead to high morbidity and mortality rates. Such morbidity usually manifests with renal failure, obstructed upper urinary tractand/or life-threatening sepsis. Prostatic abscesses have never been associated with staghorn calculi in the literature. We report a case of a 70-year-old man who presented with sepsis, which was found to originate from a complex prostatic abscess. The patient had no history of urinary tract infections or risk factors. The authors believe that the incidentally identified staghorn calculi promoted the growth of Proteus mirabilis which led to the development of the prostatic abscess. The patient underwent a transurethral resection and drainage of the abscess following a failed course of antibiotic therapy. This case also highlights the paucity of guidelines available in treating prostatic abscesses.

Validation of a Full-Immersion Simulation Platform for Percutaneous Nephrolithotomy Using Three-Dimensional Printing Technology.

INTRODUCTION AND OBJECTIVES: The restriction of resident hours with an increasing focus on patient safety and a reduced caseload has impacted surgical training. A complex and complication prone procedure such as percutaneous nephrolithotomy (PCNL) with a steep learning curve may create an unsafe environment for hands-on resident training. In this study, we validate a high fidelity, inanimate PCNL model within a full-immersion simulation environment. METHODS: Anatomically correct models of the human pelvicaliceal system, kidney, and relevant adjacent structures were created using polyvinyl alcohol hydrogels and three-dimensional-printed injection molds. All steps of a PCNL were simulated including percutaneous renal access, nephroscopy, and lithotripsy. Five experts (>100 caseload) and 10 novices (<20 caseload) from both urology (full procedure) and interventional radiology (access only) departments completed the simulation. Face and content validity were calculated using model ratings for similarity to the real procedure and usefulness as a training tool. Differences in performance among groups with various levels of experience using clinically relevant procedural metrics were used to calculate construct validity. RESULTS: The model was determined to have an excellent face and content validity with an average score of 4.5/5.0 and 4.6/5.0, respectively. There were significant differences between novice and expert operative metrics including mean fluoroscopy time, the number of percutaneous access attempts, and number of times the needle was repositioned. Experts achieved better stone clearance with fewer procedural complications. CONCLUSIONS: We demonstrated the face, content, and construct validity of an inanimate, full task trainer for PCNL. Construct validity between experts and novices was demonstrated using incorporated procedural metrics, which permitted the accurate assessment of performance. While hands-on training under supervision remains an integral part of any residency, this full-immersion simulation provides a comprehensive tool for surgical skills development and evaluation before hands-on exposure.

Treatment selection for urolithiasis: percutaneous nephrolithomy, ureteroscopy, shock wave lithotripsy, and active monitoring.

Urolithiasis is a significant worldwide source of morbidity, constituting a common urological disease that affects between 10 and 15% of the world population. Recent technological and surgical advances have replaced the need for open surgery with less invasive procedures. The factors which determine the indications for percutaneous nephrolithotomy include stone factors (stone size, stone composition, and stone location), patient factors (habitus and renal anomalies), and failure of other treatment modalities (ESWL and flexible ureteroscopy). The accepted indications for PCNL are stones larger than 20 mm2, staghorn and partial staghorn calculi, and stones in patients with chronic kidney disease. The contraindications for PCNL include pregnancy, bleeding disorders, and uncontrolled urinary tract infections. Flexible ureteroscopy can be one of the options for lower pole stones between 1.5 and 2 cm in size. This option should be exercised in cases of difficult lower polar anatomy and ESWL-resistant stones. Flexible ureteroscopy can also be an option for stones located in the diverticular neck or a diverticulum. ESWL is the treatment to be discussed as a option in all patient with renal stones (excluding lower polar stones) between size 10 and 20 mm. In addition, in lower polar stones of size between 10 and 20 mm if the anatomy is favourable, ESWL is the option. In proximal ureteral stones, ESWL should be considered as a option with flexible ureteroscopy Active monitoring has a limited role and can be employed in post-intervention (PCNL or ESWL) residual stones, in addition, asymptomatic patients with no evidence of infection and fragments less than 4 mm can be monitored actively.

Percutaneous nephrolithotomy for staghorn stones: a randomised trial comparing high-power holmium laser versus ultrasonic lithotripsy.

OBJECTIVE: To compare high-power holmium laser lithotripsy (HP-HLL) and ultrasonic lithotripsy (US-L) for disintegration of staghorn stones during percutaneous nephrolithotomy (PCNL). PATIENTS AND METHODS: A non-inferiority randomised controlled trial was conducted between August 2011 and September 2014. Inclusion criteria were patients' aged >18 years who had complete staghorn stones (branching to the three major calyces), without contraindications to PCNL. Eligible patients were randomised between two groups: HP-HLL and US- . A standard PCNL in the prone position was performed for all patients. The only difference between the treatment groups was the method of stone disintegration. In the first group (HP-HLL), a laser power of 40-60 W (2 J, 20-30 Hz) was used to pulverise the staghorn stone into very small fragments, which could pass through the Amplatz sheath with the irrigation fluid. US-L,with suction of the fragments, was used in the second group. The primary outcome (stone-free rate) was evaluated with non-contrast computed tomography after 3 months. Secondary outcomes of complications, blood transfusion, operative time, and haemoglobin deficit were compared. The outcome assessor was 'blinded' to the treatment arm. RESULTS: The study included 70 patients (35 in each group). The baseline characteristics (age, sex, body mass index, side, stone volume, and density) and operative technique (number, size of tracts, and need for second PCNL session) were comparable for both groups. Operative time was significantly shorter in US-L group, at a mean (SD) of 130 (34) vs 148.7 (35) min (P = 0.028). The haemoglobin deficit was significantly more with in the US-L group, at a mean (SD) of 1.7 (0.9) vs 1.3 (0.6) g/dL (P = 0.037). The differences in blood transfusion (17% for US-L vs 11% for HP-HLL) and the complication rates (34% for US-L vs 23% for HP-HLL) were not significant (P = 0.495 and P = 0.290, respectively). The stone-free rates at 3 months were comparable (60% for US-L and 66% for HPL-L; P = 0.621). CONCLUSIONS: Compared with US-L for intracorporeal lithotripsy of staghorn stones during PCNL, HP-HLL showed comparable safety and efficacy with a lower haemoglobin deficit but longer operative time.

The New Generation Mini-PCNL System - Monitoring and Controlling of Renal Pelvic Pressure by Suctioning Device for Efficient and Safe PCNL in Managing Renal Staghorn Calculi.

INTRODUCTION: In order to better control renal pelvic pressure (RPP), reduce surgical complications and increase operative efficacy of minimally invasive percutaneous nephrolithotomy (MPCNL), we designed an MPCNL with intelligent monitoring and control of RPP and sought to explore its clinical efficacy and characteristics. SUBJECT AND METHODS: This study included 60 patients with renal staghorn calculi. A 5F ureteral catheter was connected to an invasive blood pressure monitor for monitoring and control of RPP. A 12F renoscope was inserted through a percutaneous tract for lithotripsy using a laser, with the help of an intelligent system to monitor RPP continuously, which includes an irrigation and suctioning platform and an integrated intraluminal pressure sensory PCNL suctioning sheath. Before the lithotripsy, intraluminal pressure control value and perfusion flow were set on the platform. RESULTS: RPP was maintained at a range of -12 to 2 mm Hg. The mean operative time was 120 min. The mean intraoperative bleeding amount was 100 ml. Fifty-two of the 60 patients the stones were cleared by one surgery. CONCLUSIONS: In our suctioning MPCNL with the intelligent control of RPP, the intraoperative RPP could be accurately controlled within the preset safety range. The stone clearance rate was high.

Conservative management of staghorn calculi: a single-centre experience.

OBJECTIVE: To evaluate the outcomes of conservatively managed staghorn calculi, specifically looking at morbidity and mortality, incidence of infections and progressive changes in renal function. PATIENTS AND METHODS: A total of 22 patients with unilateral or bilateral staghorn calculi, who were treated conservatively, were included in the study. Patients were reviewed yearly with symptom assessment, urine culture and measurement of estimated glomerular filtration rate. RESULTS: The presentations to the urology department of staghorn calculi were incidental (41%), haematuria (36%), abdominal discomfort (5%) and recurrent urinary tract infections (UTIs; 18%). The reasons for conservative management in the cohort were comorbidities (59%), patient choice (36%) or poor access/anatomy (5%). In the whole cohort the rate of recurrent UTIs was 50%, the progressive renal failure rate was 14%, the disease-specific mortality rate was 9%, the dialysis dependence rate was 9% and the rate of hospital attendances attributable to stone-related morbidity was 27%. Comparison of outcome measures between the unilateral and bilateral staghorn stones showed statistically significant differences in disease-specific mortality (0 vs 40%) and morbidity (12 vs 80%) in favour of the unilateral group. Although there was a lower incidence of UTIs (41 vs 80%), renal deterioration (6 vs 40%) and dialysis requirement (6 vs 20%) in the unilateral group, these findings were not statistically significant. CONCLUSIONS: From the results, we conclude that conservative management of staghorn calculi is not as unsafe as previously thought. Careful patient selection to include unilateral asymptomatic stones with minimal infection, and thorough counselling with regard to the risks, could make conservative management a suitable option for specific patient groups.