Measurement of 'free' gold in patients receiving disodium aurothiomalate and the association of high free to total gold levels with toxicity

• Published in: Annals of the rheumatic diseases Vol. 47; no. 1; pp. 18 - 21
• Main Author: Heath, M J
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and European League Against Rheumatism 01.01.1988; BMJ; BMJ Publishing Group LTD
• Subjects: Arthritis, Rheumatoid - blood; Arthritis, Rheumatoid - drug therapy; Biological and medical sciences; Bones, joints and connective tissue. Antiinflammatory agents; Gold - blood; Gold Sodium Thiomalate - adverse effects; Gold Sodium Thiomalate - therapeutic use; Humans; Medical sciences; Pharmacology. Drug treatments; Human; Chemotherapy; Gold Compounds; Toxicity; Rheumatoid arthritis; Diseases of the osteoarticular system
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard.47.1.18

Serum from patients with rheumatoid arthritis (RA) receiving disodium aurothiomalate was analysed for total gold by atomic absorption spectrometry and for unbound (free) gold by the same method after ultrafiltration by an inert membrane. It was shown that it is possible to obtain reliable free gold concentrations by this method. Good correlations were shown between total and 'free' gold and between total and protein bound gold (PBG) for 54 patients with RA who were stabilised on gold therapy. Significant correlation was also shown between the same parameters for a second group of 15 patients starting gold therapy who were bled at weekly intervals for nine weeks immediately before medication. A single correlation with regression for all patients studied again showed good correlation between total and free gold and between total and PBG. Of the 189 paired values plotted, 182 fell within 2SD of the regression lines for the two plots. Of the seven patients with results outside 2SD of the regression line, six presented with side effects during the study.