We just recently finished discussing renal physiology in class. The functions and importance of the kidney was discussed. Clinical discussions of kidney diseases were also discussed, one of them being kidney stone disease or nephrolithiasis. Kidney stones are a hard mass that forms in the urinary tract. Once the stone is in the ureter it causes bleeding and extreme pain. A Kidney stone can lead to kidney damage, and once a stone forms its formation will reoccur. Stones for when substances that aren’t soluble in the urine, leading to crystals to form, assemble and grow. Kidney stones are mostly composed of insoluble calcium of oxalate and phosphate. There can be an excessive amount of calcium in the urine due to genetics, diet, or an idiopathic cause. Stones can also be formed by ammonium magnesium phosphate, uric acid and cysteine.
Although painful, most stones are small enough that they can pass the urinary tract. The stone can be studied microscopically and chemical studies may be done to determine what kind of stone it is. This will provide useful information for treatment. Either a diet change will be recommended or thiazide diuretics can be given in reducing calcium excretion if hypercalciuria is the problem. Potassium citrate is given because it inhibits the crystallization of calcium. If the stone does not pass spontaneously then shock wave lithotripsy is used. The patient is placed in water and x-ray imaging is sued to localize the stone. Sound waves are generated through the water which will break up the stone. This will allow the stones to pass through the ureter. This procedure can damage the kidney so it should be avoided in those who have kidney disease. Another option would be using an uretroscope with a laser to break up stones.