Types and Causes of Renal Stone - kidney stone

 Types and Causes of Renal Stone

Types of Renal (Kidney) Stone

There are four main types of kidney stones.

Calcium stones

Most kidney stones are made of calcium compounds ,especially calcium oxalate. Calcium phosphate and other minerals also may be present. Conditions that cause high calcium levelsin the body, such as hyperparathy- roidism, increase the risk of calcium stones. High levels of oxalate also increase the risk for calcium stones.

Uric acid stones

Some kidney stones are made of uric acid, a waste product normally passed out of the body in the urine.

Struvite stones

Some kidney stones are struvite stones. They can also be called infection stones if they occur with kidney or urinary tract infections (UTIs). These types of kidney stones sometimes are also called staghorn calculi if they grow large enough.

Cystine stones

Less common are kidney stones made of a chemical called cystine. Cystine stones are more likely to occur in people whose families have a condition that results in too much cystine in the urine (cystinuria).

Causes of Kidney Stones

There is no consensus as to why kidney stones form.

Heredity:

Some people are more susceptible to forming kidney stones, and heredity may play a role. The majority of kidney stones are made of calcium, and hypercalciuria (high levels of calcium in the urine) is one risk factor. The predisposition to high levels of calcium in the urine may be passed on from generation to generation.

Geographical location:

There may be a geographic predisposition to forming kidney stones, so where a person lives may make it more likely for them to form kidney stones. There are regional stone belts, with people living in the southern United States having an increased risk of stone formation. The hot climate in this region combined with inadequate fluid intake may cause people to be relatively dehydrated, with their urine becoming more concentrated and allowing chemicals to come in closer contact to form the nidus, or beginning, of a stone.

Diet:

Diet may or may not be an issue. If a person is Susceptible to forming stones, then foods high in animal proteins and salt may increase the risk, however, if a person is not susceptible to forming stones, diet probably will not change that risk.

Medications:

People taking diuretics (or water pills) and those who consum exces calcium-containing antacids can increase the amount of calcium in their urine and potentially increase their risk of forming stones. Taking excess amounts of vitamins A and D are also associated with higher levels of calcium in the urine. Patients with HIV who take the medication indinavir (Crixivan) may form indinavir stones. Other commonly prescribed medications associated with stone formation include phenytoin (Dilantin) and antibiotics like ceftriaxone (Rocephin) and ciprofloxacin (Cipro).