III. TREATMENT (Tables 13 and 14)
Of our 28 patients, 2 were lost to follow-up immediately after
diagnosis and so did not undergo surgery. 1 patient with end-stage renal
failure had ureterostomy in France. So only 25 patients had at least one major
surgical procedure mentioned in Table 13. A
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total of 20 endoscopic resections were done, 1 in Britain and 1
in France.
BLOCKSOM vesicostomies were done in 6. 2 were closed by the
end of the study after endoscopic ablation. Of the remaining 4, 2 were yet to
be closed amongst which one, who had vesicostomy at the age of 3 weeks was lost
to follow-up and was later seen at the age of 6 years in the prospective phase
of the study ; and 2 had died at 2 days post -op. of septicaemia. BLOCKSOM
vesicostomy is a tubeless bladder diversion. It was first performed by BLOCKSOM
in 1956 in a 75 year old man with carcinoma of the urethra (42). The advantages
are that it is tubeless, readily reversible, easy to perform and does not
require any appliance. By decompressing the urinary tract it allows a very ill,
often azotemic and septic child to recover from the long-term effects of
obstruction or severe reflux (42). Definitive reconstructive surgery can be
postponed until the patient's condition is optimal, renal function has improved
or stabilized, infection is finished or until the patient's size is more
appropriate for the particular procedure.
All the patients who underwent cystostomy later underwent
endoscopic ablation. Two cases of catheter ablation were done before the advent
of endoscopic surgery in Cameroon. 1 later underwent endoscopic resection and
the other went into end-stage renal failure and died.
Secondary procedures were performed in only 11 patients. High
diversions were performed in 6 cases - 3 ureterostomies and 3 nephrostomies for
severe bilateral hydronephrosis. All the ureterostomies and nephrostomies were
closed Primary ureteroplasties were done in 4 patients. One patient had
urethrostomy for meatal stenosis following catheter ablation done elsewhere.
Catheter ablation is abandoned in our institutions since the advent of
endoscopic surgery.
Although controversy still exists as to the management of PUV,
the current attitude is a primary valve ablation followed by observation and
vesicostomy reserved for patients in whom valve ablation is not technically
possible or in a child with severe renal failure .(43, 44,31,45). The long-term
outcomes with primary diversion and primary valve ablation are the same, but
performance and reversibility of diversion
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requires more major surgical procedures (31).
IV. OUTCOME OF THE PATIENTS (Table 15)
The overall mortality was 21 %. COULIBALY et al (18) had 15%;
FALL et al (20)14%, LOTTMAN (46) 4% and WARSHAW et al (38) 4.5%. 10 patients
(36%) were lost to follow-up
Causes of deaths: 3 died of septicaemia, 2 post-obstructive
diuresis and 1 of chronic renal failure
* Septicemia:1 patient (2 months old) died 2 days after an
emergent vesicostomy for uraemia, from Pseudomonas septicaemia. l (3 months)
died of klebsiella sepsis and cardiac decompensation and 1 (2 years old) died
of klebsiella pneumonia and Enterobacter cloacae septicaemia one week
after having undergone endoscopic resection and ureteroplasty for bilateral
hydronephrosis.
* Chronic renal failure: The patient who died of chronic renal
failure was 18 years old. He had undergone catheter ablation in the neonatal
period, developed end-stage renal failure at 7 and had a kidney transplantation
(the donor was the mother) in France. Before transplantation he had had a
nephrostomy and several peritoneal dialysis. Back home in Cameroon, he was on
immunosuppressors (Cyclosporine and Azathioprine) developed skin Kaposi
sarcoma, severe lung infection graft rejection and died.
* Post -obstructive diuresis: One patient (9 days old) died 2
days after an emergency BLOCKSOM vesicostomy for uraemia. The other 4 months
old died 2 months after endoscopic resection, in a hospital out of Yaounde. He
had developed gastro-enteritis, and this added to the polyuria he has been
having and inadequate dehydration caused severe dehydration and death.
Post-obstructive diuresis is persistent polyuria following
valve ablation or relief of any obstruction of the urinary (47, 48). This can
provoke a dramatic urinary loss of salt and water and hypotonic urine. Severe
polyuria carries a risk of dehydration, particularly with diarrhoea and
vomiting or high solute feeds (47). There are two major causes: (48)
1) Urea, through its osmotic effect and possibly natriuretic
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which inhibit the reabsorption of NaCl and water in the proximal
and distal tubules.
2) Obstruction per se, possibly through increased pressure within
the renal pelvis
inhibits the reabsorption of fluid and loss of urine
concentration ability. Appropriate but cautious fluid replacement should be
administered to patients with post-obstructive diuresis depending in large, on
what is excreted.
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