Læknablaðið - 15.12.1997, Page 50

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LÆKNABLAÐIÐ 1997: 83
Nýr doktor í læknisfræði
Þann 15. nóvember 1996 varöi Ársæll Krist-
jánsson doktorsritgerð við Háskólann í Lundi.
Ritgerðin nefnist Urinary diversion. Long-
term renal function and morphology and con-
sequences for metabolism. Ágrip úr ritgerðinni
fer hér á eftir:
Urinary diversion is most commonly per-
formed for high grade, high stage carcinoma of
the bladder requiring cystectomy. Other ma-
lignant diseases of the organs in the small pel-
vis and neurogenic bladder disorders are in-
dications that require urinary diversion in
some patients. In children congenital malfor-
mations like bladder exstrophy and other dis-
orders associated with severe urinary inconti-
nence are not uncommon indications for this
form of treatment. Intestinal segments of var-
ying lenghts and types are being increasingly
used for reconstructing the lower urinary tract.
Use of intestinal segments alters the normal
urinary tract anatomy and physiology with a
consequent potential threat to the renal func-
tion. Also, the flux of ions across the intestinal
mucosa when in contact with urine, with pos-
sible consequences on acid-base and electro-
lyte status, demands well-preserved renal
function to compensate for this.
In an experimental study with refluxing or
antirefluxing ureteric implantation in a low-
pressure enterocystoplasty, bacteriuria and
pyelonephritis were more common in kidneys
with refluxing anastomosis (p<0.05) The mi-
croorganisms were the same in the renal pelves
as in the cystoplasty suggesting ascending in-
fections. Despite low filling pressure in the
cystoplasty cortical scarring was seen on gross
examination in five kidneys, all with refluxing
anastomosis.
In a long-term prospective follow-up in pa-
tients randomized to an ileal or colonic con-
duit, with implantation of one ureter using an-
tireflux technique and the other without, the
fall in the preoperative mean total GFR (using
:'lCr-EDTA) exceeded the expected age-relat-
ed decline. The fall in the preoperative mean
separate GFR (using renal scintigraphy) did
not differ between refluxing and antirefluxing
anastomosis. Patients with a continent caecal
reservoir (antireflux anastomosis) compared
favourably with those who had undergone a
conduit urinary diversion. Severe renal scar-
ring (using wTc-DMSA) was associated with
refluxing ureteric implantation in most pa-
tients. The fall in preoperative mean separate
GFR was significantly greater in kidneys with
moderate or severe scarring than in those with
no or only slight scarring (p= 0.017). Urine
cultures from the renal pelvis showed bacteriu-
ria on the side with refluxing anastomosis in
most of the kidneys investigated, all with ipsi-
lateral scarring. The cultures were negative in