Kidney Stones Lecture Notes

Overview

• Kidney Stones: Hard masses of crystals that form in the kidneys, ureters, bladder, or urethra.
• Largest Recorded: Weighed more than a kilogram and 17 cm in diameter.
• Formation: Crystals form when urine compounds (calcium, sodium, potassium, oxalate, uric acid, phosphate) clump due to high levels or extreme pH.
• Growth: Crystals grow over weeks to years into stones.

Types of Kidney Stones

• Calcium Oxalate Stones: Most common, ~80% of cases.
• Calcium Phosphate & Uric Acid Stones: Less common.
• Struvite Stones: Formed by bacterial infection, composed of magnesium ammonium phosphate.
• Rare Stones: Result from genetic disorders or certain medications.

Symptoms

• Pain: Sharp edges of stones scratch urinary tract walls, causing intense pain.
• Other Symptoms: Blood in urine, nausea, vomiting, burning sensation during urination.
• Complications: Large stones can block urine flow, leading to infection or kidney damage.

Treatment

• Small Stones (< 5mm): Usually pass naturally; drink water, take painkillers.
• Slightly Larger Stones: Medications like alpha blockers relax muscles; potassium citrate dissolves stones.
• Medium Stones (Up to 10mm): Treated with extracorporeal shock wave lithotripsy (ultrasonic energy).
• Large Stones: May require invasive methods:
  • Stents: Expand ureter.
  • Lasers: Break stones.
  • Surgery: Remove stones via incision.

Prevention

• Hydration: Drink plenty of water to dilute compounds.
• Diet: Limit high oxalate foods (potato chips, spinach, rhubarb, beets).
• Calcium Intake: Foods with calcium help bind oxalate in digestive tract, preventing absorption into kidneys.

Current Trends

• Prevalence: Rates of kidney stones are rising.
• Future Records: Unlikely to break the world record for the largest kidney stone soon.