A 55-year-old woman presents with severe pain in the right flank. The pain began suddenly after supper and increased dramatically over the next hour. Urinalysis shows blood but no signs of infection. Abdominal x-ray reveals bilateral renal stones (Figure 68-1). A noncontrast CT scan confirms multiple bilateral renal stones, with an obstructing right distal ureteral stone and enlargement of the right kidney (Figure 68-2). She is subsequently found to have hyperparathyroidism, which is the cause of her multiple stones.
Plain x-ray of the abdomen in a 55-year-old woman showing several stones in the right kidney (red arrow) and a large left ureteral stone (white arrow) adjacent to the L2-L3 disc space. (Courtesy of Karl T. Rew, MD)
Noncontrast CT of the abdomen and pelvis of the same woman showing several of the stones seen in Figure 68-1, including a nonobstructing stone in the interpolar region of the right kidney. Because the right ureter is obstructed by a distal stone (not visible on this image), the right kidney is enlarged, with collecting system dilation and perinephric stranding. The large left proximal ureteral stone seen in this image is only partially obstructing, causing mild dilation in the left kidney collecting system. Several small stones are visible in the left kidney, and the left kidney is somewhat atrophied from chronic obstruction. (Courtesy of Karl T. Rew, MD)
A kidney stone is a solid mass that forms when minerals crystallize and collect in the urinary tract. Kidney stones can cause pain and hematuria, and may lead to complications, such as urinary tract obstruction and infection.
Kidney stone, nephrolithiasis, renal calculus, renal stone, urinary tract stone, ureterolithiasis, urolithiasis.
- The prevalence of kidney stones is increasing in the United States.1 More than 5% of adults have kidney stone disease, with a lifetime risk of 13% for men and 7% for women.
- Men between the ages of 40 and 60 years have the highest risk of stones; for women, the risk peaks in their 50s.2
- African Americans have a lower rate of kidney stones than white Americans.1
- Calcium oxalate and calcium phosphate stones are the most common, occurring in 75% to 85% of patients. Struvite (magnesium ammonium phosphate) stones occur in 5% of cases. Uric acid stones occur in 5% to 10% of patients and cystine stones occur in 1% of cases. Other types of stones are less common.3
- Calcium stones are more common in men than in women (ratio 2:1), whereas struvite stones are more common in women than in men (ratio 3:1).3
- Kidney stones form when there is supersaturation of otherwise soluble materials, usually from increased excretion of these compounds or dehydration. Urine pH is a ...