Journal of Postgraduate Medicine Medknow Publications and Staff Society of Seth GS Medical College and KEM Hospital, Mumbai, India ISSN: 0022-3859 EISSN: 0972-2823 Vol. 47, Num. 1, 2001, pp. 60-61

Journal of Postgraduate Medicine, Vol. 47, Issue 1, 2001 pp. 60-61

Letter to the Editor

Management of Nephrolithiasis in Crossed Renal Ectopia

Nabi G, Kasana I, Khan M

Department of Surgery, Govt. Medical College, Srinagar, Kashmir, J&K, India.

Abstract

A 40-year-old male presented with vague lower abdominal pain of six months duration associated with recurrent dysuria. Urine microscopy showed 20-40 red cells and 30-40 pus cells per high power field. Urine culture showed E-coli. An X-ray of kidney, ureter and bladder area showed multiple radio opaque shadows lying in right lumbar region and over iliac bone area. Ultrasonsgraphy showed absence of left kidney and hydronephrotic right kidney with multiple renal stones in right renal fossa. An intravenous urogram showed crossed renal ectopia with multiple calculi and normal functioning upper moiety and poorly functioning lower moiety. He was taken up for cystoscopy and bilateral retrograde pyelography with drainage film and open pyelolithotomy. Cystoscopy showed normal capacity bladder with normally positioned ureteric orifices. A retrograde ureteropyelogram delineated normal calipe ureters. There was drainage of dye into bladder from both the moieties as seen under image intensifier. Kidneys were exposed by long lumbar incision and extended pyelolithotomy in upper moiety was carried out. Lower moiety required pyelotomy with two nephrotomies to clear the stones. Double J stents were left in both the moieties for 6 weeks. There were no intraoperative or postoperative complications. A check x-ray on second postoperative day showed complete clearance. Patient was asymptomatic without urinary tract infection at a follow up of 6 months.

The incidence of crossed renal ectopia varies between 1 in 1000 clinically to 1 in 2000 in autopsy series. (1,2) The variation in incidence is possibly due to the type of fusion. The various fusions have been described with unilateral fused kidney and inferior ectopia being the most common. The left to right cross over occurs more frequently.

In majority of the cases this condition is discovered incidentally at autopsy, or ultrasonographic screening for unrelated condition or following bone scanning. If manifestations do occur, it presents as abdominal pain and urinary tract infections. The anomalous position of kidneys and anomalous blood supply causing obstruction to the drainage has been held responsible for such presentation. The incidence of urinary tract infection is controversial. (3)

It has been presumed that these kidneys are prone to nephrolithiasis with potentially obstructive collecting systems. However, review of literature shows only 6 cases of stone disease treated in crossed renal ectopic kidneys. The anomalous position of kidneys and abnormal disposition of arterial supply pose a different surgical challenge, requiring a careful definition of renal outlines by nephrotomogram (4) or contrast enhanced computerised scans, mapping of vasculature by arteriography (5) and collecting system with drainage pattern by cystoscopy and bilateral ureteropyelography. When contemplating anatrophic pyelolithotomy or nephrectomy in a fused ectopic kidney, pattern of vasculature is important. In cases of simple pyelolithotomy it is probably not required.

The various modalities of treatment that have been used in the management of such cases start with minimal invasive therapy to open surgery. The choice of treatment depends on the size of stone, pelvicalyceal anatomy, presence or absence of obstruction and the experience of the surgeon. Open surgery is most commonly used in staghorn and multiple calculi, as was carried out in our case.

References

1. Abeshouse BS, Bhisitkul I. Crossed renal ectopia with or without fusion. Urol Inter 1959;9:63.
2. Baggenstoss AH. Congenital anomalies of kidneys. Med Clin North Amer 1972; 35:987.
3. Boutman DL, Culp DA Jr, Culp DA, Flock RH. Crossed renal ectopia. J Urol 1951; 108:30.
4. Dretler SP, Olsson CA, Pfister RC. The anatomic, radiologic and clinical characteristics of the pelvic kidneys. An analysis of eighty six cases. J Urol 1971; 105:623.
5. Rubinstein ZJ, Hartz M, Shalin N, Deutsch V. Crossed renal ectopia; angiographic findings in six cases. Am J Roentgenol 1976; 126:1035. MEDLINE