A client is prescribed alpha-blockers as part of the management of renal calculi. The nurse explains that these medications can help with stone passage by:

A. Uric acid stones may cause pain, but they do not typically present with costovertebral angle tenderness. Uric acid stones are more likely to be associated with gout and hyperuricemia.

B. Calcium oxalate stones are common and can cause pain, but they do not typically cause costovertebral angle tenderness. They are more likely to cause localized pain in the back or side.

C. This is the correct answer. Struvite stones, also known as infection stones, can cause severe pain that radiates to the back and lower abdomen. They are often associated with urinary tract infections, and the presence of an infection can lead to costovertebral angle tenderness.

D. Cystine stones are rare and are more likely to cause chronic, dull pain rather than sudden and severe pain with tenderness.

A. This statement is not correct. Limiting calcium intake is not recommended for preventing calcium oxalate stones. In fact, adequate dietary calcium can help reduce the risk of stone formation.

B. This statement is not correct. Foods high in oxalate, such as spinach and nuts, should be limited to prevent calcium oxalate stones.

C. This statement is not correct. Fruits and vegetables are essential for overall health and should not be avoided. However, some fruits and vegetables are high in oxalate, which may contribute to calcium oxalate stone formation.

D. This is the correct answer. Reducing sodium intake can be beneficial for kidney health, as high sodium intake can increase calcium excretion in the urine and promote stone formation. Additionally, processed foods may contain high levels of sodium and should be limited.