all about kidney stones

All About Kidney StonesBhavani Adusumilli,MDNephrology

www.SpringfieldClinic.com/DoctorIsIn

What are kidney stones?

• Kidney stones are crystalline structures in the urinary tract, if grown to a sufficient size can cause symptoms.

What are Kidney stones ? contd..

• A kidney stone may be as small as a grain of sand or as large as a pearl, and some are as big as golf balls.

• They may be smooth, irregular in shape, or jagged, and are usually yellow or brown in color.

• They form when there are high levels of certain substances in the urine.

Who develops kidney stones?• The National Institute of Diabetes and Kidney Disease

(NIDKD) estimates that about a million people in the United States are treated for kidney stones each year.

• Whites are more prone to kidney stones than African-Americans.

• Peak age of onset is 30 yrs.• Men 2-3 times greater risk than women

Why do we need to know more about kidney stones

• Kidney stones Increase the risk for development of Chronic Kidney disease.

• Increased risk for recurrent stone formation in patients with history of stones.

• 5-year recurrence rate after an initial event of 35% to 50% without treatment.

Chronic kidney disease-Stages

Are all kidney stones the same?

• Not all kidney stones are the same.• There are various kinds of kidney stones.• Most kidney stones in patients of western countries are

made of calcium (~80%).

What are the various kinds of kidney stones ?

• Calcium oxalate~80 % • Calcium phosphate • Uric acid • Triple phosphate stones • Cysteine • Mixed

What are the symptoms of kidney stones?

• In some instances could be Asymptomatic-Rare• Renal colic-flank pain • Nausea• Vomiting• Urinary urgency• Blood in urine• Urinary frequency

What are the risk factors for kidney Stones?

• General risk factors

Low urine volume Increased sodium intake

Risk factors for calcium oxalate and calcium phosphate stones

• Increased calcium concentration in the urine-which could be due to

Genetic factors Parthyroid gland abnormalities Diet high in oxalates (chocolates, Spinach, nuts ,start fruit, sunflower

seeds, tea, rhubarb, swiss chard) IBD (inflammatory bowel disease) Abdominal surgeries (Jejunal Bypass surgery) Obesity

Risk factors for Uric acid stones

• Very high Meat intake• Gout• Obesity• Genetic causes

Risk factors for Triple Phosphate stones

• Multiple urinary tract infections• Diabetes mellitus• Chronic analgesic use• Chronic indwelling urinary catheter• Bladder emptying problems

How are kidney stones diagnosed?

• Intravenous pyelogram (IVP). A series of X-rays of the kidney, ureters, and bladder with the injection of a contrast dye.

• Computerized tomography (CT or CT scan• Urinalysis. Laboratory examination of urine• Blood tests. Laboratory examination of the blood to detect

substances that might promote stone formation.• Renal ultrasound. • 24 hr urine tests

Treatment Options?

Medical treatment • Increasing water intake to maintain urine volume of >2.5

lit• Dietary changes-Low sodium, low protein and normal

calcium• In patients with calcium oxalate stones recommend

restriction of oxalate in the diet.• Medications

Medications -1

Thiazides• The risk for composite stone recurrence was lower in

persons treated with thiazide than placebo or control (24.9% vs. 48.5%) .

• Thiazide diuretics reduce urinary calcium and are often prescribed for patients with hypercalciuria,

Medications-2

Citrate• data from 4 trials showed that composite stone

recurrence was lower in patients treated with citrate than placebo or control (11.1% vs. 52.3%).

• Citrates bind to calcium and decrease urine acidity,

Medications-3

Allopurinol• Reports on composite stone recurrence showed that risk

for recurrence was lower in patients treated with allopurinol than placebo (33.3% vs. 55.4%). 

• Allopurinol decreases uric acid in urine. 

Surgical treatment

• It is indicated if stones grow bigger in size and not able to pass through the urinary tract(>10 mm in size).

• Shock waves or extracorporeal shock wave lithotripsy (ESWL).

• Ureteroscope. • Tunnel surgery (also called percutaneous

nephrolithotomy).

What can you do to Prevent Kidney stones?

• Achieve a daily urine volume >2.5 lit• Limiting salt intake• Low protein• Normal calcium diet.• Low oxalte diet if calcium oxalte stones• Avoid Soda• Increase citrus drinks (for certain types of stones)

How does lowering sodium intake prevent Kidney stone formation?

• Low sodium intake will decrease calcium excretion in urine , thus preventing stone formation

• Recommend less than 2000 mg of sodium per day.

• Average American diet includes at least 3500mg to 5000 mg of sodium per day.

Date of download: 5/15/2015

From: Dietary and Pharmacologic Management to Prevent Recurrent Nephrolithiasis in Adults: A Clinical Practice Guideline From the American College of PhysiciansDietary and Pharmacologic Management to Prevent Recurrent Nephrolithiasis

Ann Intern Med. 2014;161(9):659-667. doi:10.7326/M13-2908

Summary of the American College of Physicians guideline on dietary and pharmacologic management to prevent recurrent nephrolithiasis in adults.ESRD = end-stage renal disease.

Figure Legend:

Copyright © American College of Physicians. All rights reserved.

Prevention contd….

• Evidence also did not show any difference between tap water and a specific brand of mineral water (Fiuggi brand oligomineral water).

• Reduced risk for stone recurrence by limiting soft drinks acidified by phosphoric acid, such as colas.

Urine Studies-Litholink

• Questions….