Treatment of Staghorn Calculi

The Official News magazine of the American Urological Association

TREATMENT OF STAGHORN CALCULI: SANDWICH OR MULTIPLE BITES? -AN ASIAN EXPERIENCE
Dr.Mahesh Desai, Gujarat, India

 

 

Introduction:

Staghorn calculus represents advanced, complex calculogenesis, especially in developing countries. The management strategy for such complex calculi depends on total stone burden, location and configuration of the stone within the collecting system, status of renal function, degree of hydronephrosis, presence of urinary tract infection, patient compliance and the cost of treatment.

 

The AUA Nephrolithiasis Panel on Staghorn Calculus recommends combination therapy, which consists of initial percutaneous removal followed by extracorporeal shock wave lithotripsy (SWL) as the preferred approach for most complex renal calculi.

 

However, combination therapy, incorporates a wide spectrum of treatments depending on the contributions of percutaneous and extracorporeal shock wave components. At one end of the spectrum, there is percutaneous debulking through a solitary tract, with high reliance on SWL for residual stones. At the other end of the spectrum is a strategy that we have used, consisting of aggressive percutaneous treatment using multiple tracts and stages, with the goal of complete stone clearance. In this scenario SWL is reserved for the occasional case in which percutaneous removal is deemed either difficult or dangerous.

 

Various strategies have been advocated to improve the efficacy of combination therapy for complex staghorn calculi. Lam et al used flexible nephroscopy to enhance calculus clearance. Streem introduced the concept of sandwich therapy, consisting of initial stone debulking followed by SWL for the residual stone burden especially in upper calices followed by percutaneous extraction of fragmented calculi. Additional cost and higher incidence of infective and ancillary procedures may be limitations of these approaches.

 

The optimal strategy for treatment of staghorn calculi must take into consideration health and economic outcome of any surgical intervention. The stone-free requirement is global, but the economic implication is regional. A high dependence on SWL may increase the morbidity and uncertainty of the outcome thus increasing the overall cost. Percutaneous Nephroslithotomy (PCNL) may be associated with fewer complications and a lower rate of secondary procedures and, therefore, may provide a cost advantage. Various reports attest to the cost effectiveness of the percutaneous treatment of renal calculi. We have adopted a philosophy of aggressive percutaneous treatment, using multiple tracts and stages, with the goal of complete clearance in a single hospital stay.

 

Materials and Methods: During the last 10 years we have treated 505 staghorn calculi in 474 patients. These included 283 (56%) partial staghorns, 146 (29%) complete staghorns and 76 (15%) complex calculi, with a mean stone bulk of 1289 mm2. A solitary kidney was present in 76 patients and 56 patients were in the pediatric age group. Calculus disease was complicated by urinary tract infection in 20% of cases, and renal insufficiency in 19% of cases.

Technique:

PCNL is aimed at reducing morbidity associated with multiple tracts. We use ultrasound to achieve percutaneous renal access. Achieving optimum access to the pelvicalyceal system is the most important step to a successful PCNL. The ideal puncture should be straight, traversing the shortest distance from skin to target calyx, and then to the infundibulum and pelvis in a straight line. This line would traverse minimum distance through the renal cortex and potentially avoid all major intrarenal vessels. A prospective study recently completed at our institute comparing ultrasound and fluoroscopy guided access revealed decreased bleeding and complications with ultrasound guidance.

 

Based on calculus and pelvicaliceal anatomy the number and site of percutaneous tracts are predetermined. At the outset the urologist obtains all percutaneous tracts. The primary tract through which the greatest stone burden can be cleared is dilated up to 28 Fr, and an Amplatz working sheath is positioned. Subsequent stone disintegration is performed out using pneumatic lithotripsy. The secondary tracts are sequentially dilated up to 22 Fr and a pediatric nephroscope is used to disintegrate residual stones. If the procedure has to be terminated because of significant bleeding, nephrostomy tubes are placed through the unused tracts and the procedure is completed at a subsequent stage. Dilating such mature tracts may result in a significantly lower blood loss.

Results:

Complete calculus clearance was achieved in 83% of patients with PCNL monotherapy. With addition of SWL in 50 cases and ureteroscopy in 2 the stone free rate increased to 90%. PCNL necessitated a single tract in 33%, 2 tracts in 36%, or multiple tracts (more than 2) in 30% of patients. The procedure required a single stage in 37%, 2 stages in 50%, and more than 2 stages in 13% of patients to clear the stone. The overall drop in hemoglobin was 1.9 gm%, and the procedure related blood transfusion rate was 12%. Most bleeding episodes were treated conservatively with 4 patients requiring angio-embolization and 1 requiring nephrectomy to treat intractable bleeding. Other complications included perforation (6%) and postoperative infection (26%).

 

When comparing morbidity between single and multiple tracts, blood transfusion and overall complication rates are higher for multiple tracts but the major complications are similar in both groups. Of 87 patients with preexisting renal insufficiency, renal function normalized in 33%, improved in 47%, deteriorated in 13%, and progressed to end stage renal disease requiring dialysis in 7%.

Conclusion:

 

Our strategy of treating complex staghorn calculi aggressively with multiple tracts and stages has achieved stone clearance in almost 90% cases. Modifying the technique of percutaneous surgery may help reduce the morbidity and complication rates associated with such an aggressive approach. This approach may prove cost effective to the patient as well as the hospital, which is of specific relevance in developing countries.

References:

 

  1. Segura, J. W., Preminger, G. M., Assimos, D. G., et al.: Nephrolithiasis clinical guidelines panel summary report on the management of staghorn calculi. J Urol, 151: 1648, 1994.
  2. Lam, H. S., Lingeman, J. E., Newman, D. M., et al.: Evolution of the technique of Combination therapy for staghorn calculi: A decreasing role for Extracorporeal Shock Wave Lithotripsy. J Urol, 148: 1058, 1992.
  3. Streem, S.B.: Sandwich therapy. Urol Clin N Amer, 24: 213, 1997.
  4. Chandhoke, P. S.: Cost-effectiveness of different treatment options for staghorn calculi. J Urol, 156: 1567, 1996.
  5. Rao, P.P., Desai, M.R., Sabnis, R.B., et al. The relative cost effectiveness of PCNL and ESWL for medium sized (<2 cm) renal calculi in a tertiary care referral center. Ind J Urol 17:121, 2001.
  6. Kukreja, R., Desai M.R., Patel S.H., et al. Ultrasound versus fluoroscopic access for percutaneous renal surgery: Prospective randomized comparison. J Urol (Submitted).