12a.) Urinary Tract Obstruction

Question 1

State some intraluminal causes of ureteric obstruction

Answer 1

• Stones
• Sloughed papilla
• Clots (e.g. if cancer in ureter that has bled)

Question 2

State some intramural causes of ureteric obstruction

Answer 2

• Pelvi-ureteric junction obstruction
• Upper transitional cell carcinoma
• Benign strictures (TB, surgical)

Question 3

State some extraluminal auses of ureteric obstrution

Answer 3

• Retroperitoneal malignancy e.g. lymph nodes mets from breast, gynae, prostrate or other malignancy
• Direct obstrution by tumour e.g. bladder cancer, locally advanced prostrate cancer
• Retroperitoneal fibrosis

Question 4

Describe how acute ureteric obstruction presents

Answer 4

• Acute, severe flank pain may radiate to groin
• Nausea/vomitting
• Usually a unilateral problem
• May also have pyonephrosis (super-added infection)

Question 5

What is obstructive uropathy?

Answer 5

Structural or functional disorder leading to impaired urinary flow

Question 6

Describe how chronic ureteric obstrution presents

Answer 6

• Generally painless (PUJ is an exception)
• Unilateral or bilateral
• May also present with pyonephrosis

Question 7

How do we diagnose upper tract obstruction?

Answer 7

• Imaging: USS, CT (note: these don’t show functional problems)
• Diuresis renogram: help determine funtional cause

Question 8

What do we mean by the following terms:

• Intraluminal cause of ureteric obstruction
• Extraluminal cause of ureteric obstruction
• Intramural cause of ureteric obstruction

Answer 8

• Intraluminal= inside ureter lumen
• Extraluminal= something outside of ureter
• Intramural= wall of ureter

Question 9

What is pyonephrosis?

Why usually occurs

Potential consequence

State symptoms and signs of pyoneprhosis

Answer 9

• Infection in kidney where pus collects in kidneys
• Usually occurs due to obstruction of ureters
• Possible consequence: sepsis
• Symptoms and signs:
  
  • Flank pain
  • Temp
  • Nausea or vomitting
  • Little or no urine
  • Nausea/vomitting

Question 10

How do you treat pyonephrosis?

Answer 10

Urological emergency in which kidney needs decompressing to try and prevent it leading to sepsis

Question 11

What is hydronephrosis?

Answer 11

Collection of excess urine in kidneys

Question 12

Give a potential cause of non-obstructive hydronephrosis

Answer 12

• Vesicoureteric reflex in children and in pregancy

Question 13

Describe how a diuresis renogram is performed

Answer 13

• Inject radiopharmaceutical
• Give diuretic
• Computer/gamma cameras measures how much radioactivity coming from differeent parts of urinary system over time
• Should fall as it’s excreted if theres no obstruction

Question 14

State two treatment options to aid upper tract drainage

Answer 14

• JJ stent: drains urine from kidney to bladder
• Nephrostomy: drains urine from renal pelvis to outside of body

Question 15

What is pelviureteric junction obstruction?

Is it congenital?

Symptoms?

Treatment?

Answer 15

• Narrowing of PUJ which leads to obstruction
• Congenital (hence can present with antenatal hydronephrosis on USS)
• Can be asymptomatic however classical presentation:
  
  • Loin pain
  • Worse after heavy fluid intake or alcohol (Dietl’s crisis)
• Treatment: laparoscopic pyeloplasty

Question 16

What is pyeloplasty?

Answer 16

Surgical reconstruction of renal pelvis to remove blockage

Question 17

Describe how retroperitoneal fibrosis can cause upper urinary tract obstruction

Answer 17

Fibrosis forms around ureters compressing them

Question 18

State some causes of retroperitoneal fibrosis

Answer 18

• Idiopathic
• Malignant
• Auto-immune (IG-G4 disease- also causes autoimmune pancreatisis)
• Drugs
• AAA

Question 19

Describe how you treat retroperitoneal fibrosis that is causing urinary obstruction

Answer 19

• Decompression of ureters
• Exclusion of malignancy
• Steroids/immunosupressants
• Uretorlysis (free ureter from fibrosis)

Question 20

Infravesical obstruction is clinically referred to as?

Answer 20

Urinary retention

Question 21

State the different types of urinary retention

Answer 21

• Acute urinary retention
• Chronic urinary retention
  
  • High pressure
  • Low pressure

Question 22

Compare the presentations of acute and chronic urinary retention

Answer 22

Acute

• Painful
• Inability to void
• Residual volume 300ml-1500ml

Chronic

• Painless
• May still be voiding
• Residual volume 300ml-4000ml

Question 23

State some causes of urinary retention in men and in women

Answer 23

Question 24

Who is urinary retention more common in, men or women? Why?

Answer 24

Men as they have prostrate (which is common cause of lower urinary symptoms)

Question 25

Describe how we investigate acute urinary retention Describe how we treat acute urinary retention

Answer 25

_Investigate_ * Catheterise and record residual volume * History * Exam (abdo, ext genitalia, DRE) * Urine dip * U&E's *(note: kidney function should be normal in acute)* _Treatment_ * Treat any obvious cause e.g. constipation * Alpha blocker in men (relax smooth muscle in prostrate) * TWOC 1-2 after being started on alpha blocker * TURP if TWOC fails

Question 26

Describe how you could tell, based on clinical investigations, whether chronic urinary retention is high or low pressure

Answer 26

High pressure * Abnormal U&Es * Hydronephrosis Low pressure * Normal renal function * No hydronephrosis

Question 27

Compare high and low pressure urinary retention

Answer 27

* High pressure: large volume of urine in bladder so bladder full/stretched * Low pressure: bladder is bit floppy/enlarged so not high pressure

Question 28

Describe how we treat chronic urinary retention- highlight differences between high and low pressure treatment

Answer 28

Main idea is that treat underlying cause Low pressure * TURP (only 50% work as there is detrusor failure) * Intermittent self cathertisiation * Long term catheter High pressure * TURP (cannot TWOC without TURP)

Question 29

What is post-obstructive diuresis

Answer 29

* Increased urinary ouput once blockage is removed leading to inappropriate salt and water loss * If severe can lead to dehydration and electrolyte imbalnce so if we remove obstruction generally keep pt in overnight to monitor and means we can give them IV fluids if needed

Question 30

What is a suprapubic catheter? State some advantages

Answer 30

Catheter that drains bladder to small incision in suprapubic region Advantages * Less likely to get infection * Less damage to urethra due to long term catheter * If desire to have sexual relations but catheter needed