Evaluation of iron stores in blood donors by serum ferritin.

BACKGROUND & OBJECTIVES: Regular blood donation can lead to pre-clinical iron deficiency as well as iron deficiency anaemia. There is a need to increase the national voluntary blood donation for safe blood supply. However, there is paucity of data in the country regarding impact of regular voluntary blood donation on iron status of donors. Hence, iron stores were evaluated by serum ferritin estimation in the voluntary blood donors at Chandigarh. METHODS: 400 voluntary blood donors included in the study were divided into four groups depending upon their periodicity of blood donations. Pre-donation haemoglobin assessment was done by copper sulphate method. Serum ferritin was estimated by indirect ELISA. RESULTS: The number of female donors with deficient iron stores was more as compared to male donors. First time donors had higher mean serum ferritin levels than that in repeat donors. The frequency of donations per year was more predictive of decreased iron stores rather than the number of lifetime donations. An increase in donation frequency was accompanied by a significant decrease in serum ferritin; values <15 microg/l were found in 21 and 46 per cent of male and female donors respectively who donated once per year, in 29 and 27 per cent in those who donated twice per year and in 49 and 100 per cent in those who donated thrice per year. INTERPRETATION & CONCLUSION: Haemoglobin estimation alone in regular blood donors may not be adequate; serum ferritin estimations may need to be done to detect pre-clinical iron deficiency states. Also, iron supplementation needs to be considered in regular, repeat voluntary blood donors.

Digoxin and membrane sodium potassium ATPase inhibition in cardiovascular disease.

Kerala has a high incidence of mucoid angiopathy, metabolic syndrome X and endomyocardial fibrosis. Magnesium deficiency has been reported in these disorders even though the Keralite diet has adequate magnesium. A possible cause of magnesium deficiency is the increased digoxin, a potent inhibitor membrane Na(+)-K+ ATPase which can lead to magnesium depletion. Digoxin is known to be synthesised by the hypothalamus and other tissues and can also be obtained from plant sources in the diet. Inhibition of Na(+)-K+ ATPase can cause intracellular magnesium depletion and increase in intracellular calcium. In view of these, a study has been carried out on the activity of membrane Na(+)-K+ ATPase, using RBC membrane, serum digoxin, magnesium and glycosaminoglycan levels in patients of mucoid angiopathy, endomyocardial fibrosis and syndrome X. Significant decrease in the membrane Na(+)-K+ ATPase was observed in patients while serum digoxin levels showed an increase. Serum magnesium was significantly lower while glycosaminoglycan levels were increased. The inhibition of Na(+)-K+ ATPase activity may be due to increase in endogenous and/or exogenous digoxin. This inhibition leads to depletion of intracellular magnesium and an increase in intracellular calcium load. The role of underlying magnesium-related insulin resistance and the consequence of this intracellular magnesium and calcium alteration in the pathogenesis of these disorders is discussed.