Effect of iron deficiency on renal function.

Renal function was assessed by determining three hour creatinine clearance (THCC) values in 20 patients (13 males, seven females; age 16-55 years) of nutritional iron deficiency anaemia. Mean transferrin saturation was 4.6% (SD 2.3). Haemoglobin and THCC were determined twice at the interval of three days before therapy. All patients received total dose iron-dextran intravenously. Three days after therapy, haemoglobin and THCC were determined again. Paired 't' test was used to determine the significance of the difference. There was no significant difference between the two pretherapy mean haemoglobin values (6.1 +/- 3.5 g/dl and 5.6 +/- 4.5 g/dl; p greater than 0.2), and the two pretherapy mean THCC values (67.2 +/- 36.9 ml/min and 70.3 +/- 22.8 ml/min; p greater than 0.5). There was no significant difference (p greater than 0.5) between pre-and post-therapy mean haemoglobin levels (6.6 +/- 2.2 g/dl). The difference between the pre-therapy and post-therapy THCC (95.3 +/- 34.0 ml/min) was statistically significant (p less than 0.01). It is concluded on the basis of these results that renal function as measured by THCC is impaired in iron deficiency anaemia, and it improves significantly within three days of total dose intravenous iron-dextran therapy when there is no significant increase in haemoglobin value. This is likely to represent the effect of iron at the tissue level independent of the anaemia.