Urinary tract stones Flashcards
What makes up the majority of stones? - 3
Calcium oxalate
Magnesium ammonium phosphate
Urate
There are others but very rare
Presentation:
They may be asymptomatic!!!!
Pain:
- How severe do the patients usually say it is?
- Why is it intermittent?
- The pain is described as renal colic. What does this mean?
- What 2 other symptoms may accompany this pain?
Why is this pain different from peritonitis?
Very severe
Due to peristalsis against the obstruction
Loin to the groin (genitals/inner thighs) - the pain moves from the loin/flank region to the groin - SEVERE
N&V
Sweating - they just feel generally unwell
They are unable to get comfortable - they will be writhing around
In peritonitis, they stay very still due to the pain!!!!!
Pain:
Where is the pain felt in obstructions of the kidney?
What may obstructions of the middle of the ureter mimic?
Where is the pain felt in obstructions of the lower ureter?
What other symptom is also noticed?
What does the obstruction of the bladder or urethra cause?
Felt in the loin - between rib 12 and lateral edge of lumbar muscles
Diverticulitis
Appendicitis
Bladder irritability - frequency
Pain in scrotum
Pelvic pain
Dysuria
Voiding dysfunction occurs when there are abnormalities in the filling, storage and emptying of urine. Voiding dysfunction is often described by symptoms such as: - frequency
- urgency
- urine retention
Why is infection risk high?
Due to increased risk of voiding dysfunction - the inability to empty urine
Investigations:
What is usually found on the dipstick?
What bloods are done? - 2
A 24 hr urine can be done if they are recurrent. Think of some electrolytes that would be tested for?
Haematuria - do microscopy
FBC and CRP for infection
U&E - renal function
Calcium and phosphate Urate Citrate Sodium Creatinine
Investigations:
Imaging:
- A non-contrast CT KUB is done. What does KUB stand for?
- Why is this a good choice?
- What imaging can be sued to monitor the passage of the stones?
Kidney, ureter and bladder
It will identify all other causes of renal colic (e.e. carcinoma, retroperitoneal lymph nodes) a swell as other differentials (e.g. appendicitis).
XR KUB
Management:
Analgesia - NSAIDs are used:
- Which one is used? - D
- Route - 2
What else may be needed to stabilise the patient?
What antibiotics are prescribed if there is an infection? - 2
Diclofenac
IM/PR
Fluids and anti-emetics
Piperacillin
Tazobactum
Management:
If <5mm in the lower ureter, most pass spontaneously.
- What is the patient encouraged to do to facilitate this?
- Why is the patient encouraged to urinate into a container?
- How long does it usually take to pass?
Increase fluid intake
To catch the stone
1-3 wks
Management:
If >1cm/pain is not resolving, removal is usually needed.
- Why are nifedipine or alpha-blockers used? - 2
- Extracorporeal shock wave lithotripsy (ESWL) is used. What does it do?
- Ureteroscopy is used as the last option. What is it?
They promote stone expulsion - used to treat ureteral spasm and promotes stone passage
Uses electromagnetic energy to destroy the stone
Stone broken up with a laser
Management:
What is done if there is obstruction with pain?
What is done if there is urosepsis?
Ureteric stenting via cystoscopy - look up
Antibiotics IV and nephrostomy
Risk factors - Why now?
What foods increase oxalate levels?
What is one big factor leading to stones?
What meds may lead to reduced calcium reabsorption?
Chocolate Tea Rhubarb Strawberries Nuts Spinach
Dehydration
Furosemide
Steroids
Acetazolamide
Thiazides
Risk factors - Predisposing factors:
What infection increases the risk of magnesium ammonium phosphate stones?
Hypercalcaemia is obviously a big factor. What causes it?
What kidney disease may also lead to this?
What may the presence of gout indicate?
Urine tract abnormalities can also lead to stones. Why is FH also important?
UTI’s - recurrent
HyperPTH HyperT Addison's Cushing's Lithium Vit D excess
Renal tubular necrosis
PKD
Hyperuricosuria/high plasma urate
It increases the risk 3 fold.
Prevention:
Drinking plenty of water is the biggest advice!!!
Why are they encouraged to start a normal calcium diet, not a low calcium one?
What type of diuretic is used to treat hypercalciuria?
As low calcium increases the oxalate excretion
Thiazide - look at MOA
