2. Causes of urinary stasis
Benign prostatic hyperplasia. (enlargement)
A urethral stricture.
External meatal stenosis.
Tight phimosis.
The above will result in chronic retention, vecico ureteric reflux, bilateral hydroureter and hydronephrosis, infection and stone formation.
Retroperitoneal fibrosis,
Vesicoureteric (VUJ) and pelviureteric junction (PUJ)obstruction are the other causes of urinary stasis.
3- Infection. The exudate provides a nidus for stone formation.
Composition of stones
Calcium Oxalate
Triple phosphate
Uric acid
Cystine calcium oxalate (85%)
The commonest
Less than I cm
Radio opaque.
Irregular surface (Spiky, sea urchin)
Produces symptoms at an early stage. eg: Ureteric colic
Triple phosphate (10%)
Calcium, Magnesium, Ammonium phosphate (Struvite stones)
Radio opaque
Form in alkaline urine
There has to be an infection
with increased urease
activity which produces ammonia.
eg: Proteus mirabilis.
Smooth surface.
Asymptomatic.
Attain a large dimension.
Acquire the shape of the renal pelvis, major and minor calyceal system, hence the shape of a stag horn.
Often results in CRF because they are usually bilateral andlarge.
NB:
Uric acid and Cystine stones are rare.
Clinical features
Renal stones
Kidney is a solid organ. It cannot contract, hence the name renal colic is a misnomer. Calyceal colic is the acute onset agonizing loin pain associated with vomiting. Stag horn calculi are asymptomatic. vague loin pain is experienced by some patients Some times.
Ureteric stones (Ureteric colic)
Acute onset
Agonizing
Loin to groin pain which may radiate to the inner aspect of the thigh, labia majora or the testicles
Persistent
Responds to Pethidine
Associated with vomiting , dysuria, frequency, and haematuria
The patient is restless
Ureteric colic may be due to:
A stone
A blood clot (Clot colic)
A ureteric stricture
A ureteric tumour ( a transitional cell cancers)
External compression of the ureter (A retroperitoneal tumour)
Bladder stones
Most are asymptomatic,
Suprapubic pain.
Pain induced by movement
Pain referred to the tip of the penis.
intermittent attacks of retention of urine or intermittent flow.
Urethral stones
The narrowest part of the urethra is the external urethral meatus, Often the stone can be seen protruding through the meatus. Otherwise, patient develops acute retention. The stone will be
felt along the ventral surface of the shaft of the penis.
Treatment of ureteric colic
Pethidine 75mg IM.
Promethazine 25mg IM-if there is vomiting.
Diclofenac sodium 100mg suppository for moderate
pain.
UFR
Pus cells
Red cells
Proteins
X-ray KUB is obtained after bowel preparation with bisacodyl 4 tablets nocte. 90% of the urinary stones are radio opaque. In a plain X-ray if there is an opacity with a diameter of 1cm the differential diagnosis would be (at the
region of right hypochondrium).
Urinary stone
Biliary stone
Calcified lymph node
Continue read… Part 10
