Pediatric emergency medicine trisk 1196 1196

Nutritional iron deficiency is the most common cause of decreased hemoglobin
production in children. A peak in the prevalence of iron-deficiency anemia occurs
between 12 and 24 months of age, when dietary iron content is often insufficient
to meet the demands of a rapidly increasing red cell mass. Premature infants are
more susceptible to developing iron-deficiency anemia because iron stores at
birth are less than those found in term infants, whereas the growth (and therefore,
expansion of the red cell mass) of the premature infant is often faster than that of
term infants. The early exhaustion of iron stores in premature babies may result in
pallor by 6 months of age, whereas in normal infants, signs of iron-deficiency
anemia are uncommon before 10 to 12 months of age.
A thorough history and physical examination will provide important clues in
the diagnosis of iron-deficiency anemia. History suggestive of a lack of iron in
the diet may be readily apparent or may be recognized only after careful
questioning, particularly regarding the daily consumption of cow’s milk. The
infant with severe iron deficiency is often irritable and very pale. A compensatory
increase in cardiac output is seen. When coupled with conditions that increase
systemic demands on the heart (such as fever), this may provoke the development
of congestive heart failure (see Chapter 86 Cardiac Emergencies ).
Serum hemoglobin concentration may be as low as 2 g/dL in severe irondeficiency anemia. Red blood cells are markedly microcytic and hypochromic,
and wide variation in red cell size and shape is usually present. Although the
percentage of reticulocytes may be elevated moderately, the absolute reticulocyte
count is low.
The diagnosis of iron deficiency as the cause for an anemia can often be made
on the basis of the history alone, and treatment is usually instituted before
confirmatory laboratory studies are available. Free erythrocyte protoporphyrin, a
precursor to mature hemoglobin, is increased in iron-deficiency anemia and
readily assayed. It can be a useful measure when evaluating the severely anemic
child in the ED. Measurements of serum iron, total iron-binding capacity (TIBC),
and ferritin levels can be valuable in the emergency management of anemia if
results are rapidly available. In hospital systems when the turnaround time is
longer, these may serve as helpful confirmatory tests. The concentration of

hemoglobin in the reticulocyte (CHr) is one of the indices reported with
reticulocyte counts, and serves as a sensitive marker of response to iron therapy at
outpatient follow-up.
Other nutritional anemias, such as vitamin B12 or folic acid deficiency, are
uncommon in children in the United States. When present, these anemias are
likely associated with particular conditions such as a grossly altered diet,