Kidney Stones Flashcards
Calcium stone precipitation pH
Calcium phosphate = increased pH/alkaline
Calcium oxalate = decreased pH/acidic
Most common type of kidney stone
Calcium oxalate
Calcium phosphate
What is the only radiolucent type of stone?
Uric acid
Radiopaque stone(s)
Calcium
Struvite
Cystine
Struvite stones are made up of which 3 components?
Magnesium
Ammonium
Phosphate
Struvite stone precipitation pH
Increased pH (alkaline)
Uric acid stone precipitation pH
Decreased pH (acidic)
Cystine stone precipitation pH
Decreased pH (alkaline)
Which 2 stones precipitate in alkaline conditions?
Calcium phosphate
Struvite
Envelope or dumbbell shaped urine crystals
Calcium stones
Coffin lid urine crystals
Struvite stones
Rhomboid or rosette urine crystals
Uric acid stones
Hexagonal urine crystals
Cystine stones
Treatment for calcium stones
Hydrochlorothiazide = Ca sparing diuretic (keeps Ca out of urine)
Citrate
Stones due to infection with urease + bugs that hydrolyze urea to ammonia (alkalinizes urine)
Struvite (Magnesium, Ammonium, Phosphate)
Which 3 bacteria are urease positive?
Proteus mirabilis
Staphylococcus
Klebsiella
Stone(s) associated with staghorn calculi
Struvite –> think adult
Cystine –> think child
Risk factors for which type of stone include hot, arid climates, low urine volume, and acidic pH?
Uric acid stones
Most common stone seen in patients with gout?
Uric acid stones
Which type of stone is seen in diseases with increased cell turnover (leukemia, myeloproliferative disorders)?
Uric acid stones
Hyperuricemia increases risk
What is the genetic defect associated with cystinuria that leads to cystine stones?
Defect of tubules that results in decreased reabsorption of cysteine
Treatment for uric acid and cystine stones
Hydration and alkalinization of urine (potassium bicarbonate)
Allopurinol also given to patients with gout
What is the most common kidney stone presentation?
Calcium oxalate stone in patient with hypercaciuria and normocalcemia
Calcium oxalate crystals can result from which 3 conditions?
Ethylene glycol
Vitamin C abuse
Crohn disease
Treatment for struvite stones
Eradication of underlying infection and surgical removal of stone
(Staghorn calculi can act as a nidus for UTIs)