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
What is the definitive treatment for upper urinary tract obstruction?
Treat underlying cause
Stone - ureteroscopy and laser lithotripsy
Ureteric tumour - radical nephroureterectomy
PUJ obstruction - laparoscopic pyeloplasty
What is the presentation of lower urinary tract obstruction?
LUTS, acute or chronic urinary retention, recurrent UTIs and sepsis, frank haematuria, formation of bladder stones, renal failure and PV bleeding in women
What is included in physical examination of lower urinary tract obstruction?
Abdomen - palpable bladder
Penis - external urethral meatal stricture and phimosis
Digital rectal examination - assess prostate size
Per vaginal examination - PV bleeding, pelvic mass and maybe USS
Urinalysis - blood and signs of UTI
What investigations are done for lower urinary tract obstruction?
MSSU, flow rate study, post-void bladder residual USS, bloods - PSA, urea and creatinine, renal tract USS if renal failure or stones, flexible cystoscopy, urodynamic studies and TRUS guided prostate biopsy
What is the management for lower urinary tract obstruction?
Resuscitation
Investigations - bladder scan, USS…
Emergency treatment - urethral catheterisation or suprapubic catheterisation
Treat underlying cause
What is the definitive treatment for lower urinary tract obstruction?
Treat underlying cause
BPE - TURP
Urethral stricture - optical urethrotomy
Meatal stenosis - meatal dilation
Phimosis - circumcision
What is gold standard investigation for renal colic?
CT-KUB
What are some common types of renal stones?
Calcium phosphate
Calcium oxalate
Uric acid
Magnesium ammonium phosphate
What is the first line treatment for 50 year old man with moderate lower urinary tract symptoms, slightly enlarged prostate and poor urinary flow?
Alpha blockers
What is the treatment for 64 year old man with 2nd episode of acute urinary retention - already on alpha blocker?
TURP
What treatment for 35 year old women with temp. 40 and right loin and flank pain, CT-KUB shows 10mm stone at upper right ureter causing severe hydro-nephrosis?
Nephrostomy insertion
