Marrow iron examination in the diagnosis of iron deficiency in rheumatoid arthritis.

A moderate degree of anaemia is commonly present in patients with rheumatoid arthritis. The anaemia is usually normocytic and hypochromic and the degree of anaemia roughly parallels the activity of the disease (Nilsson, 1948; Jeffrey, 1953a). Among the varied features described in anaemia associated with arthritis are alterations in plasma volume causing anaemia through hydraemia (Robinson, 1943; Dixon, Ramcharan, and Ropes, 1955), an increased rate of red cell destruction (Mollison and Paterson, 1949; Bunim, 1954; Freireich, Ross, Bayles, Emerson, and Finch, 1954; Alexander, Richmond, Roy, and Duthie, 1956), and abnormalities in iron and porphyrin metabolism (Jeffrey, 1953b). The effect of iron therapy on anaemia in this disease has been studied by several workers. Sinclair and Duthie (1950) reported that haemoglobin levels improved with intravenous iron therapy in cases in which oral iron had proved ineffective. Ross (1950) and Jeffrey (1953a) also reported good results with intravenous iron in this condition but all these workers found numerous cases which failed to respond to this treatment. Jeffrey (1953b), in a search for prognostic factors which might indicate whether the anaemia in any given case was likely to respond to intravenous iron, was unable to derive any material help from assessment of many clinical and laboratory features of the disease. Another group of workers (Kuhns, Gubler, Cartwright, and Wintrobe, 1950) stated that the anaemia and hypoferraemia of rheumatoid arthritis were not appreciably influenced by intravenous iron. Reports on the value of intravenous iron in the treatment of this anaemia are conflicting and the indications for its use are not clear. In view of the possible dangers of this type of therapy, especially in patients who are not iron-deficient (Dameshek, 1950; Holly, 1951), it is desirable that intravenous iron should not be used except in cases of iron-