American Board of Internal Medicine (ABIM) Certification Practice Exam

Patients with chronic kidney disease (CKD) and hyperphosphatemia should be advised to follow which dietary guideline?

1. A high phosphate diet

2. A regular phosphate diet

3. A low phosphate diet

4. An unrestricted diet

The correct answer is: A low phosphate diet

Patients with chronic kidney disease (CKD) often experience hyperphosphatemia, which is an elevated level of phosphate in the blood. This condition occurs due to the kidneys' reduced ability to excrete phosphate, leading to its accumulation. Managing hyperphosphatemia is crucial because high phosphate levels can contribute to cardiovascular disease and detrimental changes in bone health, such as renal osteodystrophy. Following a low phosphate diet is essential for these patients to help control phosphate levels and mitigate the associated risks. This dietary approach includes limiting foods that are high in phosphate, such as dairy products, nuts, seeds, beans, and some processed foods that contain phosphate additives. Encouraging patients to choose foods lower in phosphate can significantly aid in maintaining more stable phosphate levels, which is critical in managing their overall health during CKD. In dietary management, it is also important for clinicians to educate patients about reading food labels and being aware of hidden sources of phosphate, especially in packaged foods, to adhere to this low phosphate guideline effectively.