Urology Flashcards
What are the risk factors for renal calculi?
- Dehydration - concentrated urine more likely to form stones
- Recurrent UTI
- Metabolic abnormalities (particularly hypercalcemia which leads to hypercalcuria)
- Urinary tract abnormalities
- Foreign bodies
- Drugs
- Family history
MORE COMMON IN CAUCASIAN MALES
Which urinary tract abnormalities may predispose to renal calculi?
Hydronephrosis, hotshot kidney, ureterocele, vesicoureteric reflux, stricture
What is the main type of renal calculus and how do they appear on imaging?
Calcium oxalate - spiky, radio-opaque on x-ray
Where do renal calculi typically deposit?
Stones form in collecting ducts and are classically deposited in:
- Pelviureteric junction
- Pelvic brim
- Vesicoureteric junction
How do renal stones present (6 presentations)?
- Renal colic - loin to groin pain, nausea and vomiting, cant lie still
- Renal obstruction - felt in loin between rib 12 and lumbar muscles, not colicky, worsened by particular movements
- Mid ureteric obstruction - mimics appendicitis/diverticulitis
- Lower ureteric obstruction - bladder irritability, penile/labial pain
- Obstruction in bladder/urethra - pelvic pain, dysuria, interrupted flow
- Pyelonephritis/UTI - pain, dysuria, haematuria
What examination findings may be present in renal calculi?
Often no tenderness on palpation, may have renal angle tenderness especially to percussion (indicates retroperitoneal inflammation)
What investigations should be done in suspected renal calculi?
BEDSIDE: obs, urinalysis (blood), MC&S, pregnancy test. 24hr urine monitoring for calcium/oxalate/urate/citrate
BLOODS: FBC, U&E, LFT, CRP, calcium, phosphate, glucose, urate
IMAGING: spiral non-contrast CT KUB (consider US for hydronephrosis/ KUB xray)
What are some predisposing factors for kidney stone formation?
- Hypercalciruia
- Drugs (loop diuretics, antacids, glucocorticoids, theophylline, vitamin D)
What symptoms indicate urgent intervention in renal stones?
Urosepsis, intractable pain or vomiting, obstruction in a solitary kidney, bilateral stones
What is the ongoing management for renal calculi?
Pain management
- NSAIDS and paracetamol
- Alpha blockers for distal ureteric stones <10mm
Antibiotics:
- As per UTI
- IV abx if unwell
Renal stones:
- Watchful waiting if <5mm
- Shockwave lithotripsy if 5-10mm (contraindicated if pregnant)
- Shockwave lithotripsy or ureteroscopy if 10-20mm
- Percutaneous nephrolithotomy if >20mm
Ureteric stones:
- Shockwave lithotripsy +/- alpha blockers if <10mm
- Ureteropscy if 10-20mm
Ureteric obstruction:
- + infection = emergency, needs urgent decompression with nephrostomy tube, insertion of ureteric catheters and ureteric stent placement
What are the main causes of urinary tract obstruction ?
Luminal:
- Calculus
- Blood clot
- Sloughed papilla
- Tumour
Mural:
- Congenital/acquired stricture
- Neuromuscular dysfunction
- Neuropathic bladder
Extra mural:
- Mass/tumour
- Retroperitoneal fibrosis
- Post surgery
- Diverticulitis
- AAA
- Prostatic obstruction
How does urinary tract obstruction affect the kidney?
- Continuing urine formation leads to rise in intraluminal pressure
- Dilatation proximal to the site of obstruction
- Compression and thinning of renal parenchyma
- Decreased size of kidney and renal damage
When kidney function is affected, it is determined obstructive neuropathy
What is hydronephrosis?
Dilation of the renal pelvis, with or without obstruction
What are the symptoms of acute urinary tract obstruction?
UPPER - loin to groin pain, infection, enlarged kidney, anuria
LOWER - severe suprapubic pain, urinary obstructive symptoms, palpable bladder , anuria , polyuria (if unilateral, compensation)
What are the symptoms of chronic urinary tract obstruction?
UPPER - flank pain, renal failure, infection, polyuria
LOWER - urinary frequency, hesitancy, poor stream , overflow incontience, distended bladder (think symptoms of BPH)
What investigations should be done in urinary obstruction?
BEDSIDE: urinalysis, MC&S
BLOODS: FBC, U&E, creatinine, PSA, specific tumour markers
IMAGING: renal USS, CT abdo pelvis (determines level of obstruction), radionuclide imaging
How is urinary obstruction not due to calculi managed?
UNILATERAL - stent, analgesia, antibiotics, treat underlying cause
BILATERAL - catheter, antibiotics, alpha blockers, treat underlying cause
What is retroperitoneal fibrosis?
Ureters get embedded in dense, fibrous tissue resulting in progressive bilateral ureteric obstruction.
May be idiopathic, autoimmune.
Required stent placement to relieve obstruction and ureterolysis
What is PUJ obstruction?
Disturbance of peristalsis of collecting system WITHOUT mechanical obstruction
What is the definition of acute and chronic urinary retention?
Acute - Sudden, painful inability to void despite having a full bladder. Medical emergency.
Chronic - Gradual development of painless retention, characterised by residual bladder volume >1L or associated with presence of distended or palpable bladder
What causes urinary retention?
Obstruction
* BPH (most likely men)
* Strictures
* Constipation
* Malignancy
* Bladder stone
* Pelvic prolapse
Drug treatment
* Antimuscarinics
* Sympathomimetics
* Tricyclic antidepressants
* Anaesthetic agents
* Morphine
Reduced detrusor contraction
* Neurogenic (cauda equina, MS)
* Postpartum/postoperative
Bladder over-distension
* Alcohol
* Post-operative pain
What investigations should be done in urinary retention?
BEDSIDE: urinalysis, C&S
BLOODS: FBC, U&E, PSA (if chronic)
IMAGING: flow analysis, bladder post-void residual volume, renal US, MRI spine
Why is PSA not useful in acute urinary retention?
It will give a false positive - defer by 2 weeks
How is acute urinary retention managed?
- Immediate catheterisation (urethral/suprapubic)
- Alpha-adrenoreceptor blocker (eg. tamsulosin) for at least 2 days before catheter removal (TWOC)
- If TWOC is unsuccesful (no void), further TWOCs can be attempted but failure may warrant long-term catheter
How is chronic urinary retention managed?
CONSERVATIVE – treat cause, voiding tips
MEDICAL – alpha-adrenoreceptor blocker and review after 4-6 weeks then every 6-12 months, consider finasteride
OTHER – indwelling catheter
NB - do not TWOC for chronic retention, either discharge with catheter until TURP or discharge with long term catheter
What is a contraindication for suprapubic catheter?
Suspected bladder cancer - there is a risk of seeding and spreading
What are the indications for an indwelling catheter?
Incontinence, repeated infection, renal dysfunction, no surgical solution
What is post obstructive diuresis?
Severe dehydration, postural hypotension and deranged U&Es following relief of urinary retention.
Patients may pass as much as 8-20L/day. Be aware in pts with renal/cardiac failure
(aiming for <200ml/hour)
What is the pathophysiology of BPH?
- Proliferation of musculofibrous and glandular layer of the prostate
- Inner transitional zone of prostate enlarges
- Enlargement of gland distorts the urethra, obstructing bladder outflow
What is the function of the prostate?
Secretion of alkaline fluid that comprises 70% of seminal volume
What are the symptoms of BPH?
Storage sx - frequency, urgency, nocturne, incontinence
Voiding sx - weak stream, dribbling, dysuria, straining
What is the normal size of the prostate? What is the normal PSA value?
<30g (size of a walnut).
PSA changes as you age, usually below 3ng/ml.
Before a PSA test men should not have had a UTI or urological intervention in past 6 weeks, ejaculated or exercised in last 48h
Also must wait 2 week post UTI and 1 month post prostatitis
How is BPH managed?
Mild-moderate - watchful waiting, avoid caffeine/alcohol, voiding tips, bladder training
Use IPSS to classify severity of LUTS
Moderate (IPSS >= 8)
1st line - alpha blockers (tamsulosin) - work by relaxing smooth muscle
2nd line, enlarged prostate - 4 alpha reductase inhibitors (finasteride) - work by shrinking the prostate
3rd line - tolterodine, darifenacin (antimuscarinics) use if persistent storage/voiding sx after treatment with alpha blocker alone
Surgery:
Transurethral resection of prostate
Transurethral incision of prostate
Retropubic prostatectomy
TULIP
How do alpha blockers work?
Relax smooth muscle in prostate and bladder neck
How do 5a reductase inhibitors work and what are the side effects?
Decrease conversion of testosterone to dihydrotestosterone so shrink the prostate itself
SE: ED, reduced libido, ejaculation issues, gynaecomastia
What are the differences between TURP, TUIP and TULIP?
TURP - moderately invasive, lots of unwanted sexual side effects (impotence) and bleeding
TUIP - less destruction, relieves pressure on urethra, fewer side effects
TULIP - uses lasers to ablate tissue, less bleeding, fewer side effects
When should prostatectomy be considered?
Prostate >80g, good surgical candidates.
This isn’t used much as the other options are better!!
What is prostatitis? What are the symptoms?
Acute or chronic (>3 months) inflammation of the prostate, usually due to s.faecalis or e.coli, or chlamydia
Causes UTI, retention, pain, haematospermia, fever, swollen/boggy prostate
What investigations should be ordered in prostatitis?
BEDSIDE: urinalysis, culture, prostatic secretion culture
BLOODS: FBC, CRP, blood cultures, PSA
IMAGING: cystoscopy, transracial US, 4-glass test
How is prostatitis managed?
Oral ciprofloxacin/levofloxacin
If pain - NSAIDS
If obstruction - catheter
If abscess - aspiration, IV abx
What are the symptoms of prostate cancer?
Prostatism (nocturia, urinary frequency, hesitancy, dysuria, terminal dribbling)
Systemic (weight loss, night sweats, bone pain ) - suggests mets
What are the RF for prostate cancer?
- Positive family history
- Age
- Increased testosterone
- African american ethnicity
- High levels dietary fat
What is the histopathology of prostate cancer?
ADENOCARCINOMAS arising in peripheral prostate.
Can spread locally via lymph or haematogenously, causing sclerotic bony lesions
What investigations are done for suspected prostate cancer?
BEDSIDE: obs, urinalysis, DRE exam
BLOODS: FBC, testosterone PSA, calcium, CRP, U&E, LFT (looking for mets)
IMAGING: 1st line is multiparametric MRI, if Likert scale >3 offer biopsy
How is diagnosis of prostate cancer confirmed?
Prostatic biopsy or MRI
If clinical suspicion of prostate cancer is high, only do MRI
How is prostate cancer staged and graded?
Staging - TNM
Grading - Gleason score from 1 to 5
How is the Gleason score calculated?
Pathologist analyses histology from two areas of tumour and adds together to get a total score from 2-10.
2-4 - indolent
5-7 - intermediate
8-10 - aggressive
How is prostate cancer managed (no mets)?
- Radical prostatectomy
- Radical radiotherapy (with hormonal therapy)
- Hormone therapy alone (not curative - elderly patients with high risk disease)
- Active surveillance (if >70yo, low risk, review PSA yearly)
How is prostate cancer managed (mets)?
- Hormonal therapy - LHRH agonists eg. goserelin and antagonists eg. degarelix
- Orchidectomy (testicular removal)
What is multi parametric MRI?
Pre-biopsy imaging, aims to accurately locate clinically significant prostate cancer and facilitate targeted biopsy
What is androgen deprivation therapy? How can you managed the side effects?
Hormone therapy used to reduce androgen levels and shrink the cancer. Used if surgery/radiation not possible. Can give LHRH agonists or antagonists.
Hot flushes - medroxyprogesterone
Sexual dysfunction - PDE5 inhibitors
Osteoporosis - bisphosphonates
What is Wilms tumour?
A childhood tumour (<3yo) of the renal tubules and mesenchymal cells - presents with abdo mass and haematuria