LONG-TERM RENAL MORPHOLOGY AND FUNCTION FOLLOWING ENTEROCYSTOPLASTY (REFLUXING OR ANTIREFLUX ANASTOMOSIS) - AN EXPERIMENTAL-STUDY

Objective To study the morphology and function of the upper urinary tr act over the long-term in dogs with an enterocystoplasty and a refluxi ng or anti-refluxing uretero-intestinal anastomosis. Materials and met hods Subtotal cystectomy and 'cup' ileocystoplasty were performed in 1 3 dogs. The right ureter was implanted into the cystoplasty with a ref luxing technique in seven and with an anti-reflux procedure in six dog s. The left renal unit acted as an intact control in 11 dogs, while in two the intramural part of the left ureter was incised to produce ref lux. Thus, of the 26 renal units, nine had a refluxing junction (anast omosis), six were anti-refluxing and 11 served as intact controls. Tot al and separate glomerular filtration rates (GFRs) were measured preop eratively and regularly thereafter, and cystometry, urography and asce nding enterocystography were performed. At necropsy, urine was obtaine d for culture from the cystoplasty and renal pelves, and both kidneys were examined histologically. Results The cystometric pressure was low in 12 of the 13 dogs; urography showed no obstruction. This fall in s eparate GFR did not differ significantly among the groups (with and wi thout reflux protection, and control units). Reflux was detected in th ree of nine renal units with refluxing anastomosis and in three of 11 control units. Bacteriuria was found in the cystoplasty in all dogs:th e incidence in the upper urinary tract was seven of eight renal units with a refluxing anastomosis, one in five of those with an anti-reflux ing anastomosis and three of nine control units. Pyelonephritis was fo und in none of the control kidneys, in six of nine kidneys with a refl uxing and in two of six with an anti-refluxing anastomosis:it was less severe in the latter. Conclusion Refluxing ureteric implantation in a low-pressure enterocystoplasty was commonly associated with bacteriur ia in the upper urinary tract and with pyelonephritis. Thus, anti-refl ux implantation was beneficial for renal preservation in this setting.