|Year : 2000 | Volume
| Issue : 1 | Page : 55-57
Mucinous (intestinal) metaplasia of renal pelvic epithelium due to PUJ obstruction
Dilip Kumar Pal, Sikha Das
Departments of Urology and Pathology, North Bengal Medical College, Darjeeling, India
Dilip Kumar Pal
"Ranikuthi", 28/1, Rudra Main Road, P.O.: Bansberia, Dist.: Hooghly, West Bengal - 712 502
Source of Support: None, Conflict of Interest: None
Keywords: Renal Pelvic Epithelium; Mucinous Metaplasia.
|How to cite this article:|
Pal DK, Das S. Mucinous (intestinal) metaplasia of renal pelvic epithelium due to PUJ obstruction. Indian J Urol 2000;17:55-7
| Case Report|| |
A 50-year-old male, presented with a history of slowgrowing huge lump in left flank for last 6 months. On examination it was found to be left kidney lump with smooth surface and firm consistency.
He had normal haemogram, urinalysis, urine culture and renal biochemical parameters. USG suggested hugely enlarged left kidney with mixed echogenecity. IVU demonstrated a non-excretion of contrast on left side with a large soft-tissue shadow in the renal region. Contrast C.T. scan showed a markedly enlarged left kidney (16 x 12 cm) with papery thin parenchyma and grossly dilated pelvicalycial system without any contrast excretion [Figure 1]. Left-sided RGP demonstrated hydronephrosis with PUJ obstruction [Figure 2].
Left-sided nephrectomy was undertaken by standard flank incision. On opening, the kidney and pelvis was distended with thick copious viscid mucinous material. Cut surface showed gross hydronephrotic changes with dilated pelvis (8.4 cm) which had a thick smooth wall with granular deposits. The renal cortex was secondarily thinned to a fibrous rim. Other significant finding was severe ureteropelvic stenosis. No calculi was present in either the kidneys or in the ureter.
Histopathology suggested features of chronic pyelonephritis with mucin-secreting cell lining of epithelium with minimum complexity. The nuclei of epithelial cell was uniform with no invasion [Figure 3].
| Comments|| |
Mucinous (intestinal) metaplasia of the urothelium is a rare condition with scant literature in which significant portion of urothelium is completely replaced by colonic type mucosa as a result of long-standing irritation. , Rarely it is seen in the urinary bladder mucosa due to long-standing indwelling catheter, calculus, chronic infection, bladder outlet obstruction, stricture urethra, prostatitis, cystocele,  bladder extrophy, neurogenic bladder,  etc. Only few cases of mucinous metaplasia of renal pelvic epithelium is reported as a result of long-standing irritation due to renal calculus,  but till now no case is reported due to PUJ obstruction.
Histologically the disease is similar with well-differentiated mucinous adenocarcinoma but differentiating features are infiltrative architectural pattern, dissecting mucin pool, muscle invasion, greater degree of anaplasia and mitotic figures. , Though these lesions may gradually progress to adenocarcinomatous changes in urinary bladder,  but in kidney there is no evidence to suggest this metaplasia is premalignant. 
| References|| |
|1.||Bullock PS, Thoni DE, Murphy WM. The significance of colonic mucosa (intestinal metaplasia) involving the urinary tract. Cancer 1987; 59: 2086-2090. [PUBMED] |
|2.||Jacobs LB, Brooks JD, Epstein JI. Differentiation of colonic metaplasia from adenocarcinoma of urinary bladder. Hum Pathol 1997; 28: 1152-1157. [PUBMED] |
|3.||Spires SE. Banks FR, Cibull ML et al. Adenocarcinoma of renal pelvis. Arch Path Lab Med 1993: 117: 1156-1160. |
[Figure 1], [Figure 2], [Figure 3]