In this work the author has attempted to gain insight into the significance of iron depletion by the use of 4 simple calculations, justification for which is found in recent articles. These are: (a) iron with which the infant is born; (b) iron retained from the food; (c) iron being used by the tissues and therefore unavailable for hemoglobin, and (d) iron combined with the total mass of hemoglobin. With these 4 figures it is possible to estimate the iron still potentially available for use (the "reserves" or "stones"). When the difference between a + b and c + d has reached about zero, depletion is considered to exist.
The following characteristics of depletion may be emphasized:
Depletion is the result of gain in weight and maximum possible usage of iron. It is therefore a normal result of growth and need not be associated with anemia.
As soon as depletion has occurred, the organism is thereafter dependent on current absorption of iron. This is ordinarily sufficient, even with a diet of milk alone, to maintain an adequate concentration of hemoglobin after about 8 to 10 months of age.
Severe anemia due to depletion alone is practically confined to premature babies whose relative gain in weight is rapid.
Severe anemia in other than premature babies is the result of a number of factors by which iron becomes unavailable or is actually diverted from hemoglobin to storage.
Response to iron medication is considerably better in infants with depletion than in those in whom some factor is present that interferes with iron utilization, and which is not connected by the mere giving of iron.
The dependence on current absorption, whether the result of depletion or non-availability, introduces a certain precariousness which is apparently characteristic of this time of life. The organism gets along from day to day if nothing happens, but may not be able to meet an emergency, whether this appears as a rapid gain in weight, or a necessity to repair damage done by severe infection.
If we consider iron deficiency as the cause of anemia, we can think of deficiency as due to a number of factors of which depletion is only one. The development and characteristics of depletion have been considered in this paper; other factors in iron deficiency will be considered in subsequent papers.
Coinheritance of HbD-Punjab/β+-thalassemia (IVSI+5 G-C) in patient with Gilbert's syndrome
