Researchers highlighted key recommendations in areas of controversy or conjecture in the management of chronic kidney disease–mineral and bone disorder (CKD-MBD) in a recent synopsis of the Kidney Disease: Improving Global Outcomes (KDIGO) 2017 clinical practice guideline update, published in the Annals of Internal Medicine.
The original update, published in Kidney International (2017;7(Suppl 1):1-59), resulted in 15 revised recommendations based on evidence of varying strengths accumulated since the 2009 KDIGO guidelines.
“This synopsis focuses primarily on recommendations for diagnosis of and testing for CKD–MBD and treatment of CKD–MBD that emphasizes decreasing phosphate levels, maintaining calcium levels, and addressing elevated parathyroid hormone levels in adults with CKD stage G3a to G5 and those receiving dialysis,” co-author Mary B. Leonard, MD, MSCE, of Stanford University School of Medicine and her colleagues stated.
Trends in laboratory values of serum phosphate, calcium, and parathyroid hormone, taken together, should guide treatment decisions, rather than single abnormalities, according to the new recommendations. Clinicians should treat only overt hyperphosphatemia and restrict calcium-based phosphate binders.
Avoiding hypercalcemia is imperative, according to the update. Clinicians should treat secondary hyperparathyroidism (SHPT) only when parathyroid hormone levels increase or persist above the upper limit of normal. Calcitriol or vitamin D analogues should not be prescribed to CKD patients not on dialysis.
Studies also confirmed that evaluating bone mineral density with dual-energy x-ray absorptiometry is valuable when it can inform treatment. Bone biopsy remains standard for diagnosis.
Dr Leonard and her colleagues acknowledged that considerable gaps in knowledge still exist. Randomized controlled trials are still needed, for example, to reveal the effects of calcium-containing vs calcium-free phosphate binders on bone accrual and arterial calcification, as well as the effects of dietary phosphate by source (such as vegetables, meat, food additives).
Cost-benefit analyses of phosphate-lowering therapies would aid clinicians, according to the authors. Likewise, a formal assessment of the relative risks and benefits of calcitriol or vitamin D analogues in patients with SHPT of varying severity would improve practice. Additionally, calcimimetics should be compared with standard therapy in CKD stage 5D patients.
Ketteler M, Block GA, Evenepoel P, et al. Diagnosis, evaluation, prevention, and treatment of chronic kidney disease–mineral and bone disorder: Synopsis of the Kidney Disease: Improving Global Outcomes 2017 Clinical Practice Guideline Update. Ann Intern Med. doi:10.7326/M17-2640
Ketteler M, Block GA, Evenepoel P, et al. KDIGO 2017 clinical practice guideline update for the diagnosis, evaluation, prevention, and treatment of CKD-MBD. Kidney Int Suppl. 2017;7(Suppl 1):1-59. doi:10.1016/j.kisu.2017.04 .001