Acute inflammatory response does not affect erythrocyte concentrations of copper, zinc and selenium

• Published in: Clinical nutrition (Edinburgh, Scotland) Scotland), 2008-02, Vol.27 (1), p.115-120
• Main Authors: Oakes, Eleanor J.C, Lyon, Thomas D.B, Duncan, Andrew, Gray, Andrew, Talwar, Dinesh, O’Reilly, Denis St.J
• Format: Article
• Language: English
• Subjects: Acute Disease; Aged; Aged, 80 and over; Arthroplasty, Replacement, Knee; Biological and medical sciences; C-Reactive Protein - analysis; Copper; Copper - analysis; Copper - blood; Erythrocyte; Erythrocytes - chemistry; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Gastroenterology and Hepatology; Humans; Inflammation - blood; Inflammation - physiopathology; Iron - analysis; Iron - blood; Male; Micronutrient; Middle Aged; Nutritional Status; Selenium; Selenium - analysis; Selenium - blood; Serum Albumin - analysis; Trace Elements - analysis; Trace Elements - blood; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Zinc; Zinc - analysis; Zinc - blood
• ISSN: 0261-5614; 1532-1983
• DOI: 10.1016/j.clnu.2007.10.003

Summary Background & aims Measuring the nutritional status of trace elements in plasma is invalidated in the presence of a systemic inflammatory response. We examined the potential of erythrocytes to assess copper, zinc and selenium status in such situations. Methods Venous blood samples were withdrawn pre-operatively and at 12, 24, 48, 72 and 168 h post-operatively from 11 patients (6 males and 5 females) who were admitted for elective knee arthroplasty. C-reactive protein, albumin, copper, zinc, selenium and iron were measured in plasma and erythrocytes. Results Plasma zinc and selenium concentrations fell significantly: 95% confidence intervals (CI)=−32% to −44% and −22% to −36%, respectively. Copper concentrations fell transiently and then increased significantly: CI=12–43%. No significant changes were seen in trace element concentrations in erythrocytes expressed either as a ratio of haemoglobin or iron concentration. Erythrocyte iron levels correlated significantly with haemoglobin ( r =0.93). Conclusions Plasma concentrations of copper, zinc and selenium are unreliable markers of status in patients with an acute inflammatory response. Erythrocyte concentrations of these trace elements may provide a more reliable measure in long-term studies of patients with a chronic systemic inflammatory response. Iron can be used instead of haemoglobin as the denominator when expressing erythrocyte concentrations of trace elements.