Possible role of cardiovascular stress induced by the volume load as a cause of anemia in hemodialysis patients: a case of a maintenance hemodialysis patient with a literature review

Abstract

BackgroundAlthough a deficiency in erythropoietin relative to decreased hemoglobin levels is presumed to be the predominant cause of renal anemia, other factors may also exist that are not fully understood.Case presentationA 58-year-old man with pyelonephritis who had been on hemodialysis for 18 years presented a gradually decreasing serum creatinine level, possibly due to voluntary dietary restrictions, accompanied by a gradual increase in the cardiothoracic ratio from 48% to 56%. Concomitantly, his hemoglobin level decreased gradually from 14.5 to 8.7 g/dL by 6 months. Although he had no symptoms of heart failure and his left ventricular ejection fraction was 66.3%, which was almost identical to his condition 2 years prior, a drastic reduction in posthemodialysis body weight from 71.0 to 68.6 kg in 9 days was performed without apparent intrahemodialysis hypotension. His cardiothoracic ratio and serum prehemodialysis N-terminal pro-brain natriuretic peptide level decreased steeply, from 56% to 49% by 2 weeks and from 6139 to 647 pg/mL by 8 weeks, followed by a gradual increase in his hemoglobin level from 8.7 to 15.1 g/dL by 3 months. The patient was administered 50 mg/day sodium ferrous citrate but no erythropoietin-stimulating agents or hypoxia-inducible factor prolyl hydroxylase inhibitors. Although a modest increase in the serum protein level was observed immediately after the rapid reduction in posthemodialysis body weight, the patient’s hemoglobin level increased markedly and gradually, suggesting an improvement in anemia rather than hemoconcentration.ConclusionsCardiovascular stress induced by the volume load is one of the causes of anemia in hemodialysis patients.