GAMUT H-22
FILLING DEFECT OR MASS IN A RENAL PELVIS, INFUNDIBULUM, OR CALYX


COMMON
*1. Blood clot (eg, trauma; neoplasm)
*2. Calculus  (See H-24, H-25-S, H-26-S)
*3. Gas (eg, air from retrograde pyelogram; percutaneous or retrograde stone removal; sinus tract or fistula; gas infection; ureterointestinal anastomosis)
4. Metastasis
*5. Neoplasm (eg, hemangioma; hamartoma; angiomyolipoma; papilloma; oncocytoma; transitional cell carcinoma  ; hypernephroma; Wilms' tumor; lymphoma G)
6. [Normal anatomic variation (eg, bifid pelvis; duplication; overlapping calyces; calyx on end)]
7. Normal renal artery or vein impression
8. Renal sinus lipomatosis 
9. [Technical (incomplete filling with contrast medium; overlying intestinal gas)]


UNCOMMON
1. Amyloidosis
2. Cholesteatoma (squamous metaplasia of urothelium)
3. Cyst (eg, parapelvic, parenchymal, hydatid)
*4. Fungus ball (esp. Candida )
5. Inflammatory polyp
*6. Leukoplakia
7. Malacoplakia
*8. Multicystic kidney with pelvoinfundibular atresia (congenital)
9. Papilla, aberrant or sloughed (eg, papillary necrosis) (See H-20)
*10. Polycystic kidney
11. Pyelitis cystica 
*12. Pyelonephritis with inspissated pus, necrotic debris (eg, suppurative; xanthogranulomatous; tuberculous)
13. Saccular aneurysm
14. Urinoma


* May fill entire renal pelvis.

[    ] This condition does not actually cause the gamuted imaging finding, but can produce imaging changes that simulate it.




References