Causes and Symptoms of Renal calculi - By: Robert Baird

What do doctors call this condition?

Renal calculi

What is this condition?

Kidney stones may form anywhere in the urinary tract but usually develop in two sections of the kidneys, the renal pelvis or the calyces. The stones are formed from calcium, phosphate, or urate compounds that are normally dissolved in the urine.

Kidney stones vary in size and may be single or multiple. They may remain in the renal pelvis or enter the ureter and may damage renal tissue. Large stones damage the tissue with pressure or cause an obstruction that backs up fluids. Most people have repeat attacks.

What causes it?

Kidney stones develop in 1 in 1,000 persons, and are more common in men (especially those ages 30 to 50) than in women. They're more common in certain geographic areas, such as the southeastern United States. Although the exact cause of kidney stones is unknown, possible contributing factors include decreased urine production; infection; urinary obstruction; excessive secretion of parathyroid hormone, renal tubular acidosis, elevated uric acid (usually with gout), defects in the body's metabolism of certain substances, and excessive intake of vitamin D or dietary calcium.

What are its symptoms?

Though it varies with the stone's size and location, pain - caused by obstruction - is the key symptom. Large, rough stones plug the opening to the ureter and increase the frequency and force of automatic contractions.

The pain usually moves from the lower back to the flank, to the pubic region, and to the genitalia. The intensity of this pain fluctuates and may be excruciating at its peak. If stones are in the renal pelvis and calyces, pain may be more constant and dull. Back pain (from stones that produce an obstruction within a kidney) and severe abdominal pain (from stones traveling down a ureter) may also occur. Nausea and vomiting usually accompany severe pain.

The person with kidney stones may also have fever, chills, blood in the urine (when stones injure a ureter), abdominal distention, pus in the urine, and, rarely, retained urine from a blockage.

How is it diagnosed?

The doctor will ask about symptoms, and then will use the following tests:

Kidney-ureter-bladder X-rays reveal most kidney stones.

Kidney ultrasound, an easily performed noninvasive test that uses high-frequency sound waves, detects obstructions and changes.

Intravenous dye and a scan confirms the diagnosis and determines size and location of stones.

Stone analysis shows their mineral content.

Urine culture of midstream sample may indicate urinary tract infection.

Urinalysis may be normal, or may show evidence of different types of stone formation.

A 24-hour urine collection may be evaluated to determine calcium, phosphorus, and uric acid excretion levels .

Blood tests may show other imbalances and may indicate gout as the cause.

How is it treated?

Because 90% of kidney stones are smaller than 5 millimeters in diameter, the doctor usually works to promote their natural passage. Along with extra fluids, he or she may prescribe antibiotics to fight the infection found in tests and may prescribe pain relievers and diuretics to prevent urine from staying in the kidney forming more stones.

If the stones are too large for natural passage, they may require surgical removal. When a stone is in the ureter, a cystoscope may be inserted through the urethra and the stone manipulated with catheters or retrieval instruments. Extraction of stones from other areas (kidney calyx or pelvis) may require surgery of the side or lower abdomen.

Procedures called percutaneous ultrasonic lithotripsy and extracorporeal shock wave lithotripsy shatter the stones into fragments for removal by suction or natural passage.

To prevent stone formation, the doctor may prescribe a low-calcium diet, drugs to prevent uric acid stones, and vitamin C to acidifY the urine. If the thyroid is involved, he or she may recommend parathyroidectomy (removal of the parathyroid gland).

About the Author

Robert Baird, author for http://www.health-diseases.org/ explains conditions and diseases with their causes, symptoms and treatment. Know about various drugs and their uses. For more details you can visit http://www.health-diseases.org/

Article Directory Source: http://www.articlerich.com/profile/Robert-Baird/20610

Additional Articles From - Home | Disease & illness | Kidney stones