Brief Communication 188 Urology Journal Vol 5 No 3 Summer 2008 Percutaneous Management of Urinary Calculi in Horseshoe Kidneys Heshmatollah Soufi Majidpour,1 Vahid Yousefinejad2 Urolithiasis in horseshoe kidney presents a unique challenge in decision-making and technical aspects of calculus treatment. We present our experience with a group of patients with symptomatic calculi in their horseshoe kidneys. We had 8 patients with 9 horseshoe kidneys bearing calculi. They all underwent percutaneous nephrolithotomy. The median size of the calculi was 21 mm (range, 12 to 45 mm). Auxiliary therapeutic procedures were required in 2 patients who had residual calculi on control imaging. The stone-free status was observed in 6 patients (75.0%) at discharge, and in 7 (87.5%) after 3 months of follow-up. Surgical complications included bleeding in 2 patients that was controlled with complete bed rest and blood transfusion, and pleural injury in 1 which was managed conservatively. Urol J. 2008;5:188-91. www.uj.unrc.ir Keywords: kidney abnormalities, kidney calculi, lithotripsy, percutaneous nephrostomy, treatment outcome 1Department of Urology, Tohid Hospital, Kurdistan University of Medical Sciences, Sanandaj, Iran 2Research Vice-Chancellorship, Kurdistan University of Medical Sciences, Sanandaj, Iran Corresponding Author: Heshmatollah Soufi Majidpour, MD Department of Urology, Tel: +98 871 328 6113 Fax: +98 871 666 4649, E-mail: h_majidpour2007@yahoo.com Received March 2008 Accepted July 2008 Occurring at an incidence of 20% to 60%, urolithiasis is the most common complication of horseshoe kidneys.(1,2) Calculi in horseshoe and ectopic kidneys present unique challenges in decision-making and technical aspects of treatment.(3) Although, adequate fragmentation could be achieved by extracorporeal shock wave lithotripsy (SWL), the anatomic abnormality prevents passage of fragments.(2,4) The stone-free rate is only 53% (range, 50% to 79%) for calculi in horseshoe kidneys treated with SWL.(5,6) In contrast, percutaneous nephrolithotomy (PCNL) has been shown to be highly successful with an overall stone-free rate of 75% to 100% in a few series.(2,5,7,8) We present our experience with PCNL in a group of patients with symptomatic calculi in a horseshoe kidney. In Tohid Hospital of Sanandaj, a city in the west of Iran, we performed PCNL for 8 patients (5 men and 3 women) with horseshoe kidney from 2004 to 2006. One patient had bilateral involvement, and therefore, underwent PCNL in both kidneys. There was at least 1 calculus larger than 2 cm in all of the patients. The indications of performing PCNL were complex multiple calculi in 2 patients, staghorn calculus in 5, and failed SWL in 2. Laboratory tests included complete blood count, blood urea nitrogen, serum creatinine, fasting blood sugar, serum sodium, serum potassium, and blood group and Rh. Radiological assessments were done by plain abdominal radiography, intravenous urography (IVU), and ultrasonography in all of the patients. All of the calculi were opaque with different degrees on Percutaneous Nephrolithotomy in Horseshoe Kidneys—Majidpour and Yousefnejad 190 Urology Journal Vol 5 No 3 Summer 2008 blood vessels enter the horseshoe kidney through the ventromedial region; however, the possibility of hemorrhage does not necessarily confine percutaneous access to the opposite side of these vessels. On the other hand, the probability of arterial hemorrhage is not more likely than that in a normal kidney, because the dorsal vessels supplying the isthmus are supported with the vertebrae and are far from the nephrostomy tract.(2) In the present study, upper pole access was used in 89% of the kidneys compared to 64% to 81% cited in other studies.(2,5,10) The use of this method provides access to the upper pole, calyxes, renal pelvis, lower calyx, ureteropelvic junction, and proximal ureter. Raj and coworkers believed that using upper pole access decreases hemorrhage, because the nephroscopic axis is along with the kidney s longitudinal axis resulting in restriction of nephroscope movement.(5) However, in a study from Egypt, upper caliceal puncture was shown as a risk factor of severe bleeding.(14) It is remarkable that although some researchers consider flexible nephroscope for upper pole access essential,(5) we achieved comparable results with a rigid nephroscope (flexible nephroscope was not available at our center).(2,5,7-9) These results are justifiable considering that the majority of our access attempts were from the upper pole, providing the opportunity to observe more calyxes by rigid nephroscope, and also that we used two access sites in case of poor access. Another explanation is that we did not have overweight patients in whom access is more difficult. Nonetheless, the use of flexible nephroscope seems to be associated with higher overall success rates. In patients with normal kidney anatomy, upper pole access often requires supracostal approach that may cause intrathoracic complications.(15) Contrary to normal kidneys, the upper pole access is not supracostal in horseshoe kidneys (due to the different position of the kidney). Thus, the risk of pleural injury is not high. In our study, only 1 patient suffered from with pleural injury that was managed conservatively. Pneumothorax has been reported to occur in 6% of the patients with horseshoe kidney.(5) The main complication in our study was excessive hemorrhage (25%) which is frequently seen in these patients (12.5% to 42%).(2,5,10) In summary, our experience in PCNL for horseshoe kidneys confirms the results of the previous studies. As a consequence, in our opinion, PCNL can be recommended for the treatment of kidney calculi in patients with horseshoe kidney as a safe and effective procedure. CONFLICT OF INTEREST None declared. REFERENCES 1. Yohannes P, Smith AD. The endourological management of complications associated with horseshoe kidney. J Urol. 2002;168:5-8. 2. Shokeir AA, El-Nahas AR, Shoma AM, et al. Percutaneous nephrolithotomy in treatment of large stones within horseshoe kidneys. Urology. 2004;64:426-9. 3. Stein RJ, Desai MM. Management of urolithiasis in the congenitally abnormal kidney (horseshoe and ectopic). Curr Opin Urol. 2007;17:125-31. 4. Kirkali Z, Esen AA, Mungan MU. Effectiveness of extracorporeal shockwave lithotripsy in the management of stone-bearing horseshoe kidneys. J Endourol. 1996;10:13-5. Complications Study Number of Patients Calcium Calculi, % Upper Pole Access, % Stone Free, % Secondary Procedure, % Minor, % Major, % Raj et al(5) 24 87.5 64.0 87.5 33.0 16.7 12.5 Lingeman and Saw(12) 17 … 81.0 84.6 73.0 24.0 5.0 Jones et al(13) 15 53.3 NA 88.8 13.3 20.0 6.0 Al-Otaibi and Hosking(10) 12 83.0 75.0 75.0 8.3 42.0 0 Darabi Mahboub et al(11) 9 … … 66.7 33.3 … … Present series 8 100.0 88.8 87.5 25.0 12.5 25.0 Table 2. Published Studies on Percutaneous Management of Calculi in Horseshoe Kidneys* *Ellipses indicate that data were not available. Percutaneous Nephrolithotomy in Horseshoe Kidneys—Majidpour and Yousefnejad Urology Journal Vol 5 No 3 Summer 2008 191 5. Raj GV, Auge BK, Weizer AZ, et al. Percutaneous management of calculi within horseshoe kidneys. J Urol. 2003;170:48-51. 6. Al-Tawheed AR, Al-Awadi KA, Kehinde EO, Abdul- Halim H, Hanafi AM, Ali Y. Treatment of calculi in kidneys with congenital anomalies: an assessment of the efficacy of lithotripsy. Urol Res. 2006;34:291-8. 7. Lojanapiwat B. Percutaneous nephrolithotomy (PCNL) in kidneys with fusion and rotation anomalies. J Med Assoc Thai. 2005;88:1426-9. 8. Mosavi-Bahar SH, Amirzargar MA, Rahnavardi M, Moghaddam SM, Babbolhavaeji H, Amirhasani S. Percutaneous nephrolithotomy in patients with kidney malformations. J Endourol. 2007;21:520-4. 9. Viola D, Anagnostou T, Thompson TJ, Smith G, Moussa SA, Tolley DA. Sixteen years of experience with stone management in horseshoe kidneys. Urol Int. 2007;78:214-8. 10. Al-Otaibi K, Hosking DH. Percutaneous stone removal in horseshoe kidneys. J Urol. 1999;162:674-7. 11. Darabi Mahboub MR, Zolfaghari M, Ahanian A. Percutaneous nephrolithotomy of kidney calculi in horseshoe kidney. Urol J. 2007;4:147-50. 12. Lingeman JE, Saw KC. Percutaneous operative procedure in horseshoe kidneys. J Urol. 1999;161 Supl:371. 13. Jones DJ, Wickham JE, Kellett MJ. Percutaneous nephrolithotomy for calculi in horseshoe kidneys. J Urol. 1991;145:481-3. 14. El-Nahas AR, Shokeir AA, El-Assmy AM, et al. Post- percutaneous nephrolithotomy extensive hemorrhage: a study of risk factors. J Urol. 2007;177:576-9. 15. Munver R, Delvecchio FC, Newman GE, Preminger GM. Critical analysis of supracostal access for percutaneous renal surgery. J Urol. 2001;166:1242-6. Acr81CB.tmp Pages from 53_10.pdf Acr81CF.tmp