Urinary obstruction + Altered voiding

Question 1

List the locations where urinary tract obstructions are likely to form

Answer 1

1. Pelvic ureteric junction
2. Pelvic brim (lower urinary tract (LUT) where ureters cross iliac vessels)
3. Vesicoureteric junction
4. Bladder urethra outlet
5. Prostate
6. Urethra

Question 2

What are the different lower urinary tract symptoms (LUTS)?

Answer 2

Storage LUTS = incontinence, urgency, frequency, nocturia

Voiding LUTS = poor stream, hesitancy, dysuria, intermittency, double voiding, retention, straining, incomplete emptying

Post-micturition LUTS = terminal dribbling

Question 3

Briefly outline symptoms, investigation, examination and management of a patient with urinary obstruction (BPH)

Answer 3

Symptoms: hesitancy, straining/taking long time to pee, weak flow, “stop-start”, urgency/frequency, urinary incontinence, feel bladder not emptied fully

Investigation: international prostate symptom score (7 symptom questions: frequency, nocturne, urgency, hesitancy, poor stream, intermittency, incomplete emptying + 1 QoL “if you were to spend the rest of your life with your urinary condition the way it is now, how would you feel about that?”

Exam: prostate-specific antigen (PSA), abdo, DRE, imaging (transracial USS)

Management: watchful waiting (drink less alcohol, caffeine, fizzy drinks etc), drugs (Doxazosin), surgery (TURP)

Question 4

Briefly outline the investigation, examination and management of a patient with urinary incontinence

Answer 4

History - quantify symptoms e.g. precipitating events, duration, how much, medical/surgical history, medications

Exam - abdomen, pelvic/genitalia, DRE, neurologic exam, mental status + mobility

Investigations - MSU, dipstick, microscopy, culture, cytology, FBC, U&Es, glucose, frequency-volume chart, urodynamics

Management - continuous requires surgery
stress requires pelvic floor training, protection pads or surgery,
urge avoid stimulants, bladder retaining, anticholinergics (oxybutynin), B3 adrenergic agonists, surgery
Urinary retention restore bladder emptying, intermittent self-catheter, surgery, a blockers (doxazosin)

Question 5

What are the different types of incontinence?

Answer 5

1. Stress
2. Urge
3. Overflow
4. Functional
5. Continuous
6. Childhood

Question 6

Identify the common causes of urinary tract stone formation

Answer 6

Crystalline growth on organic scaffold, urine is normally supersaturated with salt + minerals but metastable. Stone formers produce more crystals than normal which aggregate to form small stones

Question 7

What is the prevalence of urinary incontinence?

Answer 7

Increase with age but never normal

Question 8

What is urodynamics?

Answer 8

Study of pressure and flow during storage, transport and expulsion of urine in the urinary tract

Question 9

What are the different causes of urinary retention?

Answer 9

Benign prostatic hyperplasia (BPH)
Prostate cancer
Prostatitis 
Haematuria
Tumours
Stones
Structural, physical, neurological

Question 10

What are the most common type of urinary tract stones?

Answer 10

1) Calcium stones (80%) of which calcium oxalate are 60% e.g. hypercalciuria or hyperoxaluria
2) Struvite - form in alkaline urine that contains ammonia and caused by urinary infection by urea-splitting bacteria
3) Cystine - rare autosomal recessive tubular disorder
4) Uric acid - accumulation of irate from purine metabolism (gout)

Question 11

What are the risk factors for urinary tract stones? What is the prevalence?

Answer 11

Common (10%)
M>F
Varies with geography/climate
Age (20-30y)
Fluid intake, family history, affluence, diet, BMI

Question 12

What can urinary tract stones cause?

Answer 12

Infection, chronic inflammation, malignancy, blockage (back pressure = renal failure)

Question 13

How do urinary tract stones present?

Answer 13

Loin to groin pain
Haematuria
Vomiting
Irritative voiding symptoms

Question 14

How are urinary stones investigated and managed?

Answer 14

Investigation: history, urine dipstick, microscopy + culture, U&Es, fever, imaging

Management: observation (<4-5mm pass in urine, >7mm will not)
calcium = diuretics if hypercalciuria, normalise mineral homeostasis
struvite = antibiotics
uric acid = allopurinol
cystine = medication to lower cystinuria

Important: infected obstructed kidney requires immediate drainage!!

Question 15

How are urinary stones treated?

Answer 15

Fragmentation - extracorporeal shockwave lithotripsy (ESWL)

Ureteroscopic removal

Percutaneous nephrolithotomy