Urolithiasis - Thierfelder Flashcards
Patient reports with severe flank pain radiating to the lower abdomen, groin, testes. Patient also has hematuria. What are these symptoms for?
Kidney Stones- can be asymptomatic, cause restlessness, nausea, vomiting, ileus, “mirror pain”
Renal Colic
- severe flank pain radiation to lower abdomen, groin, or testes
- restless, ambulatory
- nausea, vomiting, ileus
- mirror pain
Urolithiasis Stone Presentation
- asymptomatic
- acute urinary obstruction - renal colic
- hematuria
Stone Ingredients
Calcium Oxalate Phosphate Uric Acid Cystine Struvite Triameterne
________ and _________ inhibit nucleation
Magnesium and Citrate
Calcium Phosphate Stones form in acidic/alkaline urine?
Alkaline - as pH increases more phosphates exist in ionic form
Uric Acid Stones form in acidic/alkaline urine?
Acidic - solubility of urate increases as pH increases
Diagnosis of Urolithiasis
Urinalysis - hematuria, cystine and struvite crystals are diagnostic
Plain Abdominal Film
IVP
Ultrasound
** Spiral CT - no contrast - very sensitive and specific
Most common stone ingredients
Calcium oxalate, calcium phosphate.
Ingredients can be: Calcium, oxalate, phosphate, uric acid, cystine, struvite(Urea broken down), triamterene
What inhibits nucleation of kidney stones
Magnesium and citrate
What inhibits nuclei or larger structures to adhere to one another
Tamm-Horsfall protein in ascending limb of henle
Calcium phosphate stones form in ______ urine; uric acid stones form in _______ urine
Alkaline, acidic
Struvite stones process
Magnesium ammonium phosphate. Normal urine is under saturated with ammonium phosphate, UTI with urease-producing organism (Klebsiella or proteus)> Alkaline urine forms struvite
Colorless eight sided envelope crystal is
Calcium oxalate
Yellow or reddish brown diamond shaped or six sided stone is
Uric acid
Cystine crystals are
Colorless, hexagon shaped
Diagnosis of Kidney stone
Urinanalysis, plain abdominal film, IVP, ultrasound, SPIRAL CT
Abdominal flatplate: what stones are radiopaque and radiolucent
Radiopaque: Calcium oxalate, calcium phosphate, mix
Radiolucent: Uric acid, xanthine, hypoxanthine
T/F: If stone is 10mm or more you normally need a urologist to take it out.
True
How to treat stone passage
80-90% pass spontaneously.
Increase fluids.
Strain urine.
Analgesia (NSAID to normal creatinine levels)
Calcium channel blocker/alpha blocker (Nifedipine/tamsulosin- Flomax)
When do you put someone in the hospital for kidney stone?
fever UTI oral analgesia ineffective intractable vomiting dehydration
Urologic management includes:
Shock wave lithotripsy (with stint)
percutaneous nephrostolithotomy
ureteroscopy
open stone surgery
Risks for kidney stones
sweating excessive sun exposure recurrent UTI neurogenic bladder gout chronic diarrhea family hx (Renal Tubular Acidosis (RTA) and cystinuria) medications
Medications that may cause kidney stones
Carbonic anhydrase inhibitors (eventually drops pH) triamterene sulfadiazone ascorbic acid Indinavir (HIV med) Topiramate (Topomax) Acetazolamide (Diamox)
What lab work could you order if someone had a kidney stone
Serum BUN Serum creatinine, calcium, PTH if hypercalcemic phosphorus, uric acid, Urinalysis (UTI, crystals, pH). Could do a 24 hour urine collection.
Preventative therapy for kidney stones
Drink more fluids (produce 2 liters of urine, 8 8oz.)
Reduce salt intake
limit animal protein to 8 oz. daily
Why would low calcium intake increase urinary oxalate
Less calcium is available in intestinal lumen to bind oxalate and prevent its absorption
What drinks increase risk of stone
Apple juice, and grapefruit. Decrease risk: coffee, tea, beer, wine. Colas made no difference. Lemonade rich in citrate. OJ will increase urine pH and citrate
What food will increase urine uric acid
Red meat, fish, poultry
Foods rich in oxalate
Spinach, nuts, PB, strawberries, chocolate, rhubarb, brewed tea
What inhibits sodium reabsorption in distal renal tubules?
Thiazides (hydrochlorothiazide). Give potassium citrate to replace potassium
Medical management of uric acid stones
Alkalinize urine to pH 6 to 6.5. pH>7 is risk for calcium phosphate stones. Give potassium citrate. Increase fluids. Dietary restriction of purines. Allopurinol
