What are risk factors for kidney stones?
Genetics, warm environment, dehydration, sedentary lifestyle and medical conditions (gout, hyperparathyroidism, hyperthyroidism, short gut, chemo, glucocorticoids)
What symptoms do people present with when they have stones?
Flank pain, uncomfortable, hematuria, nausea, vomiting, fever & chills (from infections)
What is your differential diagnosis of conditions that present with flank pain and hematuria?
What lab tests can you do to determine if someone has a kidney stone?
What is the most sensitive and specific test we have for kidney stones? What is the 2nd best?
1st = non-contrast-enhanced CT scan. 2nd = KUB radiograph (IVP). They will show 90% of stones as radio-opaque. 3rd = Ultrasound. Shows hydronephrosis if stone is blocking up kidney.
What should you see on IVP in a kidney with a kidney stone?
A white stripe of blockaded contrast dye indicating an inability to peristalsis.
When are you okay to give a patient pain for the kidney stone and wait for it to pass?
75% of calculi of 5mm or less pass spontaneously
How do you get rid of a low risk stone with medical therapy?
Alpha-1-blocker to dilate the lower ureter & prostate and normal hydration
When would you consider placing a stent or doing percutaneousl nephrostomy?
Patients with a fever and pain due to pyelonephritis from blockade. After the infection is resolved, you can go back in and get the stone.
How can you "surgically" get rid of a stone?
Ureteroscopy, Extracorporeal Shock Wave Lithotripsy (ESWL), Percutaneous Nephrolithotomy
How do you prevent stone formation?
2L of urine/day, low Na+ diet, low animal protein diet and a normal Ca2+ diet.