Elevated granulocyte strontium in inflammatory arthritides is related to the inflammatory activity

Total cellular strontium and calcium were measured by the nuclear microprobe technique. Increased mass fraction of both elements was found in granulocytes isolated from patients with active rheumatoid arthritis and other kinds of inflammatory arthritides. Increased granulocyte calcium but only marginally elevated granulocyte strontium was demonstrated in patients with scleroderma. The granulocyte accumulation of strontium and calcium seems to be linked to the degree of inflammatory activity, because the granulocyte content of both elements was positively correlated to the plasma concentration of acute-phase proteins. Corticosteroid therapy induced a marked reduction of granulocyte strontium but a more modest decrease of granulocyte calcium. The serum levels of strontium and calcium were within the normal ranges in all patients and were not significantly altered by corticosteroids.