Page 265 - Medicine and Surgery

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Chapter 6: Disorders of the bladder and prostate 261

infections. In pregnancy, low pelvic kidneys can interfere
Disorders of the bladder
with labour. They are diagnosed by IVU or renal USS.
and prostate
Congenital malformations of Bladder outflow obstruction
the ureter
Definition
Definition
Obstruction to urinary flow from the bladder to the ure-
Developmental abnormalities of the ureter are relatively
thral meatus.
common.
Incidence/prevalence
Aetiology
Common in men.
Oftensporadic,butincreasedriskinthosewithapositive
family history.
Agenesis: This occurs with renal agenesis.
Age
Atresia: Failure of the ureteric bud to canalise, associ-
Increases with age
ated with renal dysplasia.
Ectopic ureteric orifice: The ureter normally enters Sex

the bladder outside the area of the trigone. An ectopic M > F
ureter often arises from a duplex kidney, which may
be associated with vesicoureteric reflux. Occasionally Aetiology
the ureter can drain into the vagina or seminal vesicle. The causes of bladder outflow obstruction are shown in
Surgical re-implantation of the ureter may be indi- Table 6.13.
cated.
Ureterocele: The ureteric orifice is tiny, so that the

Pathophysiology
ureter dilates to form a cyst by the bladder wall. If
Areduction of >70% in the urethral lumen or vesi-
not surgically dilated, the obstruction leads to hy-
courethral junction (VUJ) causes obstruction, lead-
dronephrosis.
ing to reduced flow, increased voiding pressure and
Primary obstructive megaureter: The cause of this

condition is unknown. The whole ureter becomes di-
lated, apart from the terminal segment. If the stenosis Table 6.13 Causes of bladder outflow obstruction
is causing obstruction, treatment is with surgical re- Mechanical
implantation of the ureter. Intrinsic Foreign body, e.g. clot
Stones (rare)
Clinical features Wall Urethral valve (male neonates)
Stricture: fibrosis, usually after trauma or
Many are asymptomatic. Obstruction is chronic and
infection
therefore usually painless. Urinary stasis or reflux can Bladder neck spasm
lead to repeated urinary tract infections, which in chil- Tumour
dren may cause non-specific fevers, malaise, failure to Extrinsic Enlarged prostate (BPH or Ca)
thrive and abdominal symptoms. Prostatitis
Pregnancy
Constipation
Management and prognosis
Neuropathic Trauma to spinal cord
In recurrent infections, renal scarring results unless the Parkinson’s Disease
condition is diagnosed and treated with prevention and Guillain-Barr´e Syndrome
early detection of UTI’s and surgical repair where indi- Multiple sclerosis
Drug induced Anticholinergics
cated.Unrelievedobstructioncanalsoleadtoirreversible
Antidepressants
loss of renal function.