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Flashcards in Urolithiasis Deck (44)
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1
Q

What are the classic locations for urinary tract stones to occur?

A
  • Pelviureteric junction
  • Pelvic brim
  • Vesicoureteric junction
2
Q

What is the most common type of kidney stone?

A

Calcium oxalate

3
Q

What are the different types of stones the can occur in the urinary tract?

A
  • Calcium oxalate/phosphate
  • Cystine
  • Magnesium ammonium phosphate (struvite)
  • Urate
  • Hydroxyapatite
  • Brushite
4
Q

What are causes of urinary tract stones?

A
  • Dehydration
  • Hypercalcaemia
  • Hypercalciuria
  • Hyperparathyroidism
  • Neoplasia
  • Hyperthyroidism
  • Recurrent UTI’s
  • Hyperuricosuria
  • Cystinuria
  • Renal tubular acidosis
  • PKD
  • Drugs
5
Q

What are the common causes of hypercalcaemia leading to stone formation?

A
  • Primary hyperparathyroidism
  • Vitamin D ingestion
  • Sarcoidosis
6
Q

What are causes of hypercalciuria?

A
  • Hypercalcaemia
  • Excess dietary calcium
  • Excess resorption
  • Idiopathic
7
Q

What can cause uric acid stones to form?

A
  • Gout
  • Myeloproliferative disorders
  • Dehydration
8
Q

How does renal tubular acidosis cause stone formation?

A

Caused, in part, by the production of a persistently alkaline urine and reduced urinary citrate excretion.

9
Q

What drugs can cause bladder stones?

A
  • Calcium - Loop diuretics, antacids, glucocorticoids, theophylline, Vitamin D, acetazolamide
  • Uric acid - Thiazides, salicylates
10
Q

How do those with urinary tract calculi present?

A

Can be asymptomatic:

  • Pain - excruciating spasm; loin to groin pain; often in area where stone is affecting
  • Nausea + Vomiting
  • Signs of infection
  • Haematuria
  • Proteinuria
  • Sterile pyuria
  • Can be anuric
11
Q

If someone had an obstruction of the kidney due to stones, where might the pain be?

A

Felt in the loin, between rib 12 and lateral edge of lumbar muscle

12
Q

Where might someone experience pain if they had an obstruction caused by a stone of the mid-ureter?

A

May mimic appendicitis/diverticulitis in terms of location

13
Q

What features might indicate that a stone is obstructing the lower ureter?

A
  • Symptoms of bladder irritability
  • Pain in scrotum/penile tip/labia majora
14
Q

What features might you see in someone who has obstruction of the the bladder/urethra?

A
  • Pelvic pain
  • Dysuria
  • Strangury
  • Interrupted flow
15
Q

What is strangury?

A

Desire but inability to void

16
Q

What are people at increased risk of developing if they have urinary stones?

A

Infection

17
Q

What is the character of pain experienced in urinary stones?

A

Colicky pain - tube contracting against obstruction.

Patient is very restless, unable to find comfortable position

18
Q

What nerve root distribution is implicated in the loin to groin pain experienced in renal colic?

A

L1 - First lumbar nerve root

19
Q

What might you find on examination of someone with urinary tract stones?

A

Usually no tenderness on palpation, however may have:

  • Costovertebral angle and ipsilateral flank tenderness
  • Signs of sepsis - fever, tachycardia, and hypotension
20
Q

What investigations would you consider doing in someone with urinary stones?

A
  • Bloods - FBC, U+E’s, Ca2+, PO43-, glucose, bicarbonate, urate, PTH, coag screen
  • Urine dipstick
  • MSU + culture
  • Plain abdo x-ray/ Non-contrast CT-KUB
  • Consider
    • Renal ultrasound
    • Urine pH
    • 24hr urine collection
    • Stone biochemistry
21
Q

What is a CT-KUB?

A

CT of kidney, ureter and bladder - best diagnostic test available

22
Q

What may present similarly to renal stones?

A

Ruptured AAA

23
Q

What proportion of stones are visible on X-ray KUB?

A

80%

24
Q

Why might you do a urine dipstick?

A

Check for blood in urine

25
Q

Which sex does urinary stones occur more commonly in?

A

Males

26
Q

What might signs of sepsis in someone with renal colic indicate?

A

Obstruction with overlying infection

27
Q

How would you manage someone with acute renal colic?

A
  • Analgesia - IV/IM diclofenac
  • Hydration - crystalloids
  • Anti-emetics - ondansetron
  • If infection - Trimethoprim
28
Q

What would you do if someone had stones confirmed at <5mm diameter in the lower ureter?

A

Increase fluid intake with supportive therapy - 90-95% of stones will pass

29
Q

How long does it take for most stones treated with alpha-blockers/nifedipine to pass?

A

Most pass within 48hrs

30
Q

If stones are failing to pass/>5mm, what else would you consider doing?

A
  • Extracorporeal shockwave lithotripsyy (if <1cm diameter)
  • Percutaneous Ureteroscopy
  • Percutaneous Nephrolithotomy - with large, multiple, complex stones
31
Q

When is percutaneous nephrolithotomy used to treat urinary stones?

A
  • Renal/proximal ereteric stones
  • Those >20mm
  • Failed medical expulsion therapy/ESWL + uteroscopy
32
Q

What are indications for urgent intervention?

A
  • Presence of infection and obstruction - may need percutaneous nephrostomy/ureteric stent to relieve obstruction
  • Urospesis
  • Intractable pain/vomiting
  • Impending AKI
  • Obstruction in a solitary kidney
  • Bilateral stones
33
Q

What general advice would you give someone to prevent urinary stones?

A
  • Drink plenty
  • Normal dietary calcium
34
Q

What secondary prevention measures would you employ in someone who had had calcium stones?

A

In hypercalciuria - Thiazide diuretics

35
Q

What secondary prevention measures would you employ in someone who had had urate stones?

A
  • Allopurinol
  • Urine alklainisation - sodium bicarb/potassium citrate
36
Q

What secondary prevention measures would you employ in someone who had had cystine stones?

A
  • Vigorous hydration - >3L/day urine output
  • Urinary alkalinisation
  • Penicillamine + pyroxidine
37
Q

What might significant bacteruira indicate?

A

Mixed infective stone formation

38
Q

Why might you look at serum albumin in someone with kidney stones?

A

To correct serum calcium concentration

39
Q

Why might you look at plasma bicarbonate?

A

This is low in renal tubular acidosis. The finding of a urine pH that does not fall below 5.5 in the face of metabolic acidosis is diagnostic of this condition

40
Q

Why might you do a 24 hour urine collection?

A

To measure urinary calcium, oxalate and uric acid output

41
Q

Why might you do a coag screen in someone with urinary stones?

A

Incase there is need for nephrostomy insertion

42
Q

What would you initially do to manage someone with infection and obstruction due to urinary stone?

A
  • ABCDE and Sepsis 6
  • Drain the kidney - Nephrostomy/stent
43
Q

What is the best form of pain medication for urinary stones?

A

IM/IV/PR diclofenac

44
Q

What investigations would you consider doing to investigate the cause of urinary stones?

A
  • Bloods - Ca2+, PO43-, Albumin, PTH, urate, bicarbonate
  • Specific - urinary spot cystine, 24 hr urine collection