American Board of Internal Medicine (ABIM) Certification Practice Exam

The appropriate point for referring suitable candidates for kidney transplantation is when their estimated Glomerular Filtration Rate (eGFR) falls below 20 mL/min/1.73 m². Patients with chronic kidney disease (CKD) at this level of renal function are often approaching kidney failure, which brings them closer to needing renal replacement therapy, such as dialysis or transplantation.

This threshold is significant because it marks the stage when patients start to experience more pronounced symptoms of kidney failure and the risk of complications increases. Additionally, early referral allows for a comprehensive evaluation for transplantation, including assessing the patient's overall health, identifying any contraindications, and beginning the necessary workup for potential living or deceased donor options.

Referring at an eGFR below this level also ensures that when the need for a transplant does arise, the patient is already on the waiting list or appropriately assessed, which can help reduce the time they spend on dialysis.

In comparison, referrals at higher eGFR levels may not optimize outcomes because patients might not yet be candidates for transplantation or may not benefit from the evaluation process as they might still be managing their CKD with less urgency. Thus, the choice of less than 20 mL/min/1.73 m