Blackburne AT et al, 2016: Endoscopic Management of Urolithiasis in the Horseshoe Kidney.
Blackburne AT, Rivera ME, Gettman MT, Patterson DE, Krambeck AE.
Department of Urology, Mayo Clinic, Rochester, MN.
Abstract
OBJECTIVE: To assess the endourologic outcomes of patients diagnosed with a horseshoe kidney (HK) and symptomatic urolithiasis.
METHODS: A retrospective review was performed of patients diagnosed with an HK who underwent endoscopic management from 2002 to present.
RESULTS: We identified 45 patients with 64 stone-bearing moieties who underwent 56 procedures, of which 31 (69%) were male. Mean age was 49.4 years (23-78) and mean stone size was 1.6 cm (0.2-5.7). Of the 64 moieties, 37 (58%) underwent percutaneous nephrolithotomy (PCNL), 25 (39%) underwent ureteroscopy (URS), and 2 (3%) underwent extracorporal shockwave lithotripsy (SWL). More than one access was utilized in 2 (5.7%) moieties undergoing PCNL. Additional procedures were required in 10 (28.5%) PCNL patients, of which 7 were URS, 2 were secondary PCNL, and 1 sandwich therapy with SWL and PCNL. Stone-free rate by moiety was 81.1% for PCNL, 84% for URS, and 50% for SWL. Postoperative complications occurred in 3 patients in the PCNL group, including readmission for pain and complicated urinary tract infection. With a mean follow-up of 20.5 months (range 0-118 months), stone recurrence was noted in 7 (16%) patients with a total of 11 events. Calcium oxalate was the most common stone type and 20/24 (83%) of patients with metabolic evaluations were found to have at least onabnormality.
CONCLUSION: After careful consideration of the anatomy, individuals with HK and symptomatic urolithiasis can be managed safely by a variety of endoscopic approaches with excellent outcomes; however, secondary procedures and recurrence are common.
Urology. 2016 Jan 6. pii: S0090-4295(15)01197-8. doi: 10.1016/j.urology.2015.12.042. [Epub ahead]
Comments 1
Not unexpectedly was the success rate better with endoscopic procedures than with SWL. But the latter treatment method was selected in only 2 of the 45 patients with horseshoe kidneys. A previous report [1], however, has shown that SWL can be used in these patients with reasonably good success. Stone-treatment index [STI; 2] to get a stone-free kidney was 2.66 and to achieve satisfactory disintegration it was 4.32.
In the present study 50% (one patient) became stone-free. Only one treatment session was required with a corresponding STI of 2.66. The relatively high STI despite the small stone size is explained by the factor of abnormal anatomy in the formula. This result is similar to those published by Ray [1].
References
1 Ray AA, Ghiculete D, D'A Honey RJ, Pace KT.
Shockwave lithotripsy in patients with horseshoe kidney: determinants of success.
J Endourol. 2011 Mar;25(3):487-93. doi: 10.1089/end.2010.0213. Epub 2011 Mar 1.
2. Tiselius HG, Ringdén I.
Stone treatment index: a mathematical summary of the procedure for removal of stones from the urinary tract.
J Endourol. 2007 Nov;21(11):1261-9.