Chronic Kidney Disease, Dialysis, and Kidney Transplantation
Chronic Kidney Disease, Dialysis, and Kidney Transplantation
This domain tests CKD definition and staging, recognition of systemic complications, dialysis adequacy, and transplant immunosuppression and rejection.
Core rules
- CKD: GFR <60 mL/min/1.73 m² or markers of kidney damage for >3 months. Stage by GFR G1–G5 and albuminuria A1–A3.
- Complications: anemia from erythropoietin deficiency, CKD-mineral bone disease with high phosphate, low calcitriol, and high PTH, metabolic acidosis, and hyperkalemia.
- Dialysis adequacy: Kt/V targets; hemodialysis uses diffusive clearance, peritoneal dialysis uses osmotic and diffusive clearance.
- Transplant: induction and maintenance immunosuppression; rejection can be hyperacute, acute cellular, or antibody-mediated. BK virus nephropathy causes rising creatinine and viral load.
- Calcineurin inhibitors such as tacrolimus and cyclosporine are nephrotoxic and interact with CYP3A4 inhibitors.
Worked example
A 55-year-old with CKD G4 has phosphate 6.5 mg/dL, calcium 8.0 mg/dL, and PTH 450 pg/mL. This is secondary hyperparathyroidism from CKD-MBD. Give phosphate binders with meals, active vitamin D, and dietary phosphate restriction; monitor calcium and phosphate.
Traps
- Staging CKD by a single creatinine value.
- Overcorrecting bicarbonate and causing alkalosis.
- Missing BK virus in a transplant patient with rising creatinine.
- Ignoring drug interactions with tacrolimus.