Effect of iron supplementation on mild to moderate anaemia in pulmonary tuberculosis

Anaemia is a common complication of pulmonary tuberculosis. The precise mechanism of anaemia in pulmonary tuberculosis is not clearly known, but anaemia of inflammation as well as of Fe deficiency has been implicated. Both are common in developing countries. It is extremely difficult to distinguish anaemia of Fe deficiency from anaemia of inflammation with the haematological indices used routinely. Therefore, Fe preparations are usually prescribed for all anaemic patients irrespective of the aetiology. This approach has been questioned. The present study aimed to assess the effect of Fe supplementation on anaemic patients with pulmonary tuberculosis. Adult male patients 15-60 years of age with pulmonary tuberculosis and a blood haemoglobin concentration 80-110 g/l were included in the study; healthy adult males matched for age and socio-economic status were taken as controls. Blood haemoglobin concentration, total erythrocyte count (TEC), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin and serum Fe, total Fe-binding capacity and ferritin were estimated before treatment and 1, 2 and 6 months after treatment. The patients were divided randomly into three groups and during the initial 2 months of treatment were provided with one of three supplementary regimens consisting of placebo, Fe alone or Fe with other haematinics. Significant improvements in haematological indices and Fe status were noticed in all three groups. Blood haemoglobin concentration, MCV and PCV were significantly higher at 1 month in both Fe-supplemented groups than the placebo group. This difference, however, disappeared at 2 and 6 months with similar values in all three groups. The increase of other haematological indices was similar in all groups. Serum Fe and Fe saturation of transferrin were significantly higher in both Fe-supplemented groups than the placebo group up to 2 months; this effect, however, disappeared at 6 months. There was a consistent increase in TEC and decrease in ferritin values up to 6 months in all groups. Radiological and clinical improvement was similar in all three groups. These observations suggest that Fe supplementation in mild to moderate anaemia associated with pulmonary tuberculosis accelerated the normal resumption of haematopoiesis in the initial phases by increasing Fe saturation of transferrin. However, consistent improvement of haematological status was dependent only on the improvement of the disease process.