Combating anemia in chronic kidney disease (CKD) with erythropoietin-stimulating agents (ESAs) has been shown to improve both mental and physical factors (Iranian, 2013). Erythropoietin (EPO) is a protein hormone produced by the kidney that binds with receptors in the bone marrow and stimulates erythrocyte production (Munk, 2013). Perceptions of quality of life, cognition, sexual function, symptoms of depression and socialization are all scored higher in patients with Hb levels in near-normal range (Iranian, 2013). While the most common physical symptoms of anemia in CKD improve with ESA treatment, it is also been shown to positively effect the more severe consequences (Iranian, 2013). Improvement in cardiac function has been noted in patients diagnosed with left ventricular hypertrophy and congestive heart failure (Iran, 2013) as well as stabilized renal function in non-dialysis patients (Iranian, 2013). Treatment of anemia in CKD patients is also attributed to reducing lengths of hospital stays and decreasing mortality rates (Iranian, 2013).
While the benefits of ESA’s in combating the symptoms and consequences of anemia in CKD are indisputable, there is a wide range of treatment regimens, inconsistent parameters for treatment, and increased risk of stroke and morbidity in the pediatric population (Bamgbola, 2011). Regimens have been reported that are up to 30% different in dose and results show wide variations in patient response (Bamgbola, 2011). One factor in the inconsistencies is ESA resistance (Bamgbola, 2011). ESA resistance, also known as hypo-response, is a condition defined by one of three scenarios (Iranian, 2013). One is when there is an increasing dose of ESA required to maintain Hb within a specified range (Iranian, 2013). Two is when a consistent dose of ESA fails to maintain Hb concentration (Iranian, 2013). Third is when “an Hb concentration of ≥ 11 g/dl despite an ESA dose equivalent to epoetin > 500 units/kg/week”(Iranian, 2013). Some causes for ESA resistance, such as nutrient deficiencies, are easily corrected (Iranian, 2013). Secondary hyperparathyroidism or hematological malignancies may require a longer period of correction (Iranian, 2013). “Chronic medical conditions, such as systemic lupus erythematosus or sickle cell anemia, may not be correctable” (Iranian, 2013, p. 22). Multiple reasons exist for ESA hypo-response and because of this, highly individualized assessment and chemotherapeutic interventions are recommended (Bamgbola, 2011).
Bamgbola, O. (2011). Pattern of resistance to erythropoietin-stimulating agents in chronic kidney disease. Kidney International, 80(5), 464-474. doi:10.1038/ki.2011.179
Iranian Society of Pediatric Nephrology. (2013). ESA resistant kamyab f. Retrieved from http://iranspn.com/kongere%20va%20seminar/anemia-CKD/
Presentation1.pdf
Munk, R., PhD. (2013). Anemia. Retrieved from http://www.aidsinfonet.org/fact_sheets/view/552?lang=eng
