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630 Part VI: The Erythrocyte Chapter 43: Iron Deficiency and Overload 631

leukocytes. Potential donors are screened in blood banks, so that those effects. Increasing safety and convenience of parenteral iron therapy
with frank anemia are not phlebotomized. Yet, by the time they are may lead to reevaluation of its role in the prevention and treatment of
excluded from donation, some blood donors are iron depleted 37–39 and iron-deficiency anemia of pregnancy. 53
may readily develop iron-deficiency anemia with relatively small addi-
tional blood loss. Dietary Iron Deficiency
Factitious Anemia Factitious anemia as a result of self-inflicted In infants, iron deficiency is most often a result of the use of unsupple-
bleeding may present a formidable diagnostic and therapeutic prob- mented milk diets, which contain an inadequate amount of iron. Dur-
lem. This rare condition has also been called, in literary allusion to a ing the first year of life, the full-term infant requires approximately 160
fictitious character, “Lasthénie de Ferjol syndrome” (in Barbey d’Aure- mg and the premature infant approximately 240 mg of iron to meet the
villy’s gloomy novel, Une Histoire Sans Nom), or part of Munchausen needs of an expanding red cell mass. Approximately 50 mg of this need
syndrome (based on the Rudolf Raspe book, The Surprising Adventures is fulfilled by the destruction of erythrocytes that occurs physiologically
of Baron Münchausen). 40,41 Most patients are women, and are often during the first week of life (Chaps. 7 and 33); the rest must come from
employed in a medical setting. There is often a history of numerous the diet. Milk products are very poor sources of iron, and prolonged
blood transfusions. The anemia is chronic and may be severe. The site of breast- or bottle-feeding of infants frequently leads to iron-deficiency
induced blood loss is obscure. Hence, patients are subjected to numer- anemia unless iron supplementation is implemented. This is especially
ous radiographic and endoscopic examinations, usually to no avail. true of premature infants. The European Society for Pediatric Gas-
The patients are usually refractory to medical advice and therapy. The troenterology, Hepatology, and Nutrition (ESPGHAN) Committee on
patients may be depressed and suicidal; some also suffer anorexia ner- Nutrition urges that all infant formulas be iron-fortified ; in North
54
vosa. Psychiatric care is needed, but often is unsuccessful. Rarely, the America, the use of iron-fortified formula is now generally accepted,
outcome of self-bleeding may be fatal. 42 but there is controversy about the appropriate level of fortification.
55
Cow’s Milk Anemia Ingestion of whole cow’s milk may induce In older children, an iron-poor diet may also contribute to the devel-
protein-losing enteropathy and gastrointestinal bleeding in infants, 43,44 opment of iron-deficiency anemia, particularly during rapid growth
probably on the basis of hypersensitivity or allergy. In four such cases periods.
observed endoscopically, erosive gastritis or gastroduodenitis was Infants and young women are usually in precarious iron balance,
demonstrated as the probable source of bleeding. At least during the their iron intake being less than 80 percent of the recommended daily
first year of life, children should not be given whole bovine milk, either allowance (RDA). Fortification of bread and cereals with ferrous sul-
56
raw or pasteurized. More protracted heating, as in preparation of infant fate or metallic iron is commonplace. This practice was suspended in
formulas, eliminates this problem. Intrinsic lesions of the gastrointes- Sweden because of concern for the possibility of increasing iron storage
tinal tract, such as those listed above, may cause bleeding in infants, as in patients with the hemochromatosis genotype, resulting in increased
well as in older children. incidence of iron-deficiency anemia. 57
Respiratory Tract Persistent recurrent hemoptysis may lead to The scant iron supply of the American diet places young women
iron-deficiency anemia. It may be a result of congenital anomalies of the and children at particular risk of negative iron balance. Because the
respiratory tract, endobronchial vascular anomalies, chronic infections, adult male needs to absorb only approximately 1 mg iron daily from his
neoplasms, or valvular heart disease. Severe iron-deficiency anemia is a diet to maintain normal iron balance, iron deficiency in older men is
manifestation of idiopathic pulmonary hemosiderosis and of Good- very rarely caused by insufficient dietary intake alone.
45
pasture syndrome (progressive glomerulonephritis with intrapulmo-
nary hemorrhage). In some of these disorders, hemoptysis may not be Malabsorption of Iron
observed, but sufficient amounts of blood-laden sputum may be swal- Gastric secretion of hydrochloric acid is often reduced in iron defi-
lowed to result in positive tests for occult blood in the stools. Iron defi- ciency. Histamine-fast achlorhydria has been found in as many as 43
58
ciency occurs in a large proportion of patients with cystic fibrosis, 46,47 percent of patients with iron deficiency. Gastric function may improve
and occurs even in the absence of hemoptysis, suggesting that inflam- after correction of the iron deficiency, so that iron deficiency may be
matory inhibition of dietary iron absorption and iron loss in purulent both a cause and a result of impairment of gastric iron secretion. How-
sputum could contribute to the deficiency. ever, in persons older than the age of 30 years, the achlorhydria is usu-
ally irreversible. Furthermore, when atrophic gastritis coexists with iron
Pregnancy and Parturition deficiency, no improvement in gastric secretory function has followed
Although physiologic decrease in hemoglobin concentration is an iron therapy. Autoimmune gastritis, which is often associated with H.
expected consequence of hemodilution associated with pregnancy, true pylori infection, 14,15 may play an important role in both iron-deficiency
iron deficiency frequently results in more severe anemia. In pregnancy, anemia and, in later life, in the development of pernicious anemia.
the average iron loss resulting from diversion of iron to the fetus, blood Intestinal malabsorption of iron is quite an uncommon cause of
loss at delivery (equivalent to an average of 150 to 200 mg of iron), and iron deficiency except after gastrointestinal surgery and in malabsorp-
lactation is altogether approximately 900 mg; in terms of iron content, tion syndromes. Ten to 34 percent of patients who have undergone
this is equivalent to the loss of more than 2 L of blood. Approximately 30 subtotal gastric resection develop iron-deficiency anemia years later.
mg of iron may be expended monthly in lactation. Because most women Many such patients have impaired absorption of food iron, caused in
begin pregnancy with low iron reserves, these additional demands part by more rapid gastrojejunal transit and in part by partially digested
frequently result in iron-deficiency anemia. Iron depletion has been food bypassing some of the duodenum as a result of the location of the
reported in some 85 to 100 percent of pregnant women. Iron-deficient anastomosis. Fortunately, medicinal iron is well absorbed in post–partial
mothers are likely to have smaller babies. The incidence of anemia and gastrectomy patients. Moreover, gastrointestinal blood loss may also
iron deficiency is lower in women who take oral iron supplementation, play an important role in anemia following gastric resection (see “Gas-
daily or intermittently. 48–51 In regions with endemic malaria, iron sup- trointestinal Blood Loss” earlier). In malabsorption syndromes, absorp-
plementation may increase the risk of malaria and some recommend tion of iron may be so limited that iron-deficiency anemia develops over
52
that it be combined with malarial prophylaxis. Most experts agree that a period of years. Celiac disease, whether overt or occult, may be asso-
oral iron supplementation during pregnancy is desirable despite side ciated with iron-deficiency anemia. 14,15,59,60

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