Kidney Stones Flashcards Preview

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Flashcards in Kidney Stones Deck (25)
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1
Q

Calcium stone precipitation pH

A

Calcium phosphate = increased pH/alkaline

Calcium oxalate = decreased pH/acidic

2
Q

Most common type of kidney stone

A

Calcium oxalate

Calcium phosphate

3
Q

What is the only radiolucent type of stone?

A

Uric acid

4
Q

Radiopaque stone(s)

A

Calcium
Struvite
Cystine

5
Q

Struvite stones are made up of which 3 components?

A

Magnesium
Ammonium
Phosphate

6
Q

Struvite stone precipitation pH

A

Increased pH (alkaline)

7
Q

Uric acid stone precipitation pH

A

Decreased pH (acidic)

8
Q

Cystine stone precipitation pH

A

Decreased pH (alkaline)

9
Q

Which 2 stones precipitate in alkaline conditions?

A

Calcium phosphate

Struvite

10
Q

Envelope or dumbbell shaped urine crystals

A

Calcium stones

11
Q

Coffin lid urine crystals

A

Struvite stones

12
Q

Rhomboid or rosette urine crystals

A

Uric acid stones

13
Q

Hexagonal urine crystals

A

Cystine stones

14
Q

Treatment for calcium stones

A

Hydrochlorothiazide = Ca sparing diuretic (keeps Ca out of urine)
Citrate

15
Q

Stones due to infection with urease + bugs that hydrolyze urea to ammonia (alkalinizes urine)

A

Struvite (Magnesium, Ammonium, Phosphate)

16
Q

Which 3 bacteria are urease positive?

A

Proteus mirabilis
Staphylococcus
Klebsiella

17
Q

Stone(s) associated with staghorn calculi

A

Struvite –> think adult

Cystine –> think child

18
Q

Risk factors for which type of stone include hot, arid climates, low urine volume, and acidic pH?

A

Uric acid stones

19
Q

Most common stone seen in patients with gout?

A

Uric acid stones

20
Q

Which type of stone is seen in diseases with increased cell turnover (leukemia, myeloproliferative disorders)?

A

Uric acid stones

Hyperuricemia increases risk

21
Q

What is the genetic defect associated with cystinuria that leads to cystine stones?

A

Defect of tubules that results in decreased reabsorption of cysteine

22
Q

Treatment for uric acid and cystine stones

A

Hydration and alkalinization of urine (potassium bicarbonate)

Allopurinol also given to patients with gout

23
Q

What is the most common kidney stone presentation?

A

Calcium oxalate stone in patient with hypercaciuria and normocalcemia

24
Q

Calcium oxalate crystals can result from which 3 conditions?

A

Ethylene glycol
Vitamin C abuse
Crohn disease

25
Q

Treatment for struvite stones

A

Eradication of underlying infection and surgical removal of stone
(Staghorn calculi can act as a nidus for UTIs)