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the exact location of the kidney , variation of pelvicaliceal anatomy , stone size , and location are important factors for deciding the approach in these patients .
apart from open stone surgery , percutaneous nephrolithotomy ( with laparoscopic or ultrasonography guided needle punctures ) and laparoscopic pyelolithotomy are the treatment modalities described in the literature .
we present a case of stones in a pelvic ectopic kidney managed by transmesocolic laparoscopic pyelolithotomy .
an 11-year - old boy presented with bilateral stone disease , ie , a right upper ureteric stone and 2 radiopaque stones ( 2.3 cm  2.0 cm and 2.0 cm  0.9 cm ) in a left ectopic pelvic kidney ( figure 1 and 2 ) .
the patient was placed in a supine position after prior retrograde pyelography and placement of a double  j stent .
a veress needle was inserted through a 1.5-cm umbilical incision , pneumoperitoneum was created , and a 12-mm visualizing laparoscopic trocar ( ethicon ) was inserted into the abdominal cavity .
secondary ports , 10 mm and 5 mm , were inserted in the right and left iliac fossae , respectively , and the table was tilted to a 30 trendelenburg position .
the mesocolon of the large bowel was draped over the ectopic kidney in the pelvis overlying the sacral promontory . because the patient was quite slim , little fat was present in the mesocolon , and the pulsations and course of the vessels
we proceeded with a transmesocolic approach without mobilizing the bowel off the anterior surface of the kidney and renal pelvis .
both the stones were extracted under vision after pyelotomy , using a 10-mm right angle forceps ( figure 4 ) .
the pelvis was primarily closed using interrupted vicryl sutures and re - retroperitonealization of the kidney by suturing the overlying peritoneum .
a 14f drain was placed in the peritoneal cavity close to the kidney through the left 5-mm laparoscopic port .
plain x - ray kub showing a single stone on the right side ( white arrow ) at the level of the third lumber vertebra and 2 stones overlying the sacrum ( black arrow ) .
x - ray kub showing 2 calculi overlying the sacrum in the left ectopic pelvic kidney .
intravenous urography showing an ectopic left pelvic kidney with the stone lying in the pelvis and the calyx .
the intraperitoneal drain was removed on day 2 , and the patient was discharged 72 hours after surgery .
all 3 stones were calcium - oxalated dihydrate . the double j stent was removed 4 weeks after surgery as an office procedure with the patient under local anesthesia .
follow - up ultrasonography at 6 months revealed a normal kidney without any hydronephrosis or stones .
small stone burden in an ectopic kidney can be dealt with by shock wave lithotripsy or flexible ureteroscopy . however , larger stone sizes require more invasive procedures .
percutaneous access through a standard flank approach may not be suitable in pelvic ectopic kidneys and frequently requires modification of the technique including laparoscopic assistance to avoid inadvertent injury to the surrounding visceras .
some authors have also suggested the use of ultrasound - guided punctures to achieve percutaneous access in ectopic kidneys prior to percutaneous nephrolithotomy ( pnl ) .
desai et al utilized ultrasound - guided punctures for pnl in 9 patients for the treatment of stones in the ectopic pelvic kidneys .
notable technical factors were use of a mature tract or an amplatz sheath , routine postoperative double - j stenting , and a nephrostogram before nephrostomy tube removal .
laparoscopic guidance for achieving access to the pelvicaliceal system ( pcs ) has been used to add safety to the transperitoneal route of percutaneous nephrolithotomy .
various authors have reported successful outcomes and complete stone clearance with no intraoperative or postoperative morbidity .
this method also provides the opportunity for safe access to the pelvicaliceal system and stone clearance in a single session . because the location and configuration of the renal pelvicaliceal system of an ectopic kidney can vary
, each case requires a unique approach for surgical management of stones . in the situation of an ectopic kidney with a laterally or
thus , not only complete clearance can be achieved in a single operative session , but also postoperative morbidity can be minimized by primarily closing the opening in the pelvicaliceal system . in a similar situation ,
kamat et al have found laparoscopic pyelolithotomy to be an effective procedure with low morbidity .
in addition , a transmesocolic approach in our case avoided the additional procedure of mobilization of the bowel without any associated risk of bowel or major vascular injury and should be a viable option in select thin - built patients with ectopic kidneys .
laparoscopic pyelolithotomy can be safely and effectively performed in a pelvic kidney with a laterally or anteriorly directed pelvis without the need for ancillary modalities .
management of large calculi in ectopic pelvic kidneys poses a challenge to the urologist . 
 risk of injury to surrounding abdominal viscera and vasculature makes open surgery as well as percutaneous nephrostolithotomy in an ectopic kidney a challenging procedure . 
 laparoscopic management avoids open surgery and associated morbidity and offers added safety . 
 we report the management of symptomatic stones in a pelvic ectopic kidney lying anterior to the l5 vertebra and sacrum by transmesocolic laparoscopic pyelolithotomy in an 11-year - old child . 
 complete stone clearance was achieved with no complications and an uneventful postoperative recovery . 
 the patient was discharged 72 hours after the surgery .