Urinary Tract Obstruction Flashcards
What is included in upper tract types of obstruction?
PUJ, ureter and VUJ
What is included in lower tract types of obstruction?
Bladder neck - in men only
Prostate - men
Urethra
Urethral meatus
Foreskin - phimosis in men
What are some intrinsic causes of PUJ obstruction?
Scar tissue, stone, ureteric tumour (TCC), blood clot and fungal ball
What are some extrinsic causes of PUJ obstruction?
Crossing vessel, lymph nodes and abdominal mass (tumours)
What are some intrinsic causes for ureter obstruction?
Stone, ureteric tumour, scar tissue, blood clot and fungal ball
What are some intrinsic causes of ureter obstruction?
Lymph nodes, iatrogenic (pelvic surgery), and abdominal/ pelvic mass
What are some intrinsic causes of VUJ obstruction?
Stone, bladder tumour, ureteric tumour, and prostate cancer
Describe the presentation of upper tract obstruction
Pain, frank haematuria and symptoms of complications
Palpable mass and microscopic haematuria
What are some complications of upper tract obstruction?
Infection and sepsis
Renal failure
If upper urinary tract is obstructed then what will USS show?
Hydro-nephrosis
Hydroureter
Cause of obstruction may not be visualised
What imaging is used in upper tract obstruction?
USS, IVU, CT-KUB, CT-urogram and MAG-3 renogram
Describe MAG-3 renogram
Nuclear isotope scan to determine split renal function as proportion of global renal function and severity of obstruction
Not used in acute setting or for stones or tumours
Chronic unilateral upper tract obstruction
What is the advantages and disadvantages of CT-KUB?
For investigation of urinary tract stones and obstruction in emergency setting
Quick and low radiation
No risk of contrast nephrotoxicity
Lower sensitivity for masses
Less useful if collecting system and ureter is not dilated
What are the advantages and disadvantages of CT-urogram?
Higher radiation exposure
Risk of contrast nephrotoxicity and contraindicated in renal failure
High sensitivity for obstructing masses
What is the management for upper urinary tract obstruction?
Resuscitation
Investigations - plus imaging
Emergency treatment of obstruction - percutaneous nephrostomy insertion or retrograde stent insertion