P1: SBT
0521779407-03 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 19:6
Anemias Secondary to Systemic Disease 123autoimmune disorders, but the etiologies and treatments are differ-
ent than those for the classic anemia of chronic disease. The anemia
of renal failure is primarily due to erythropoietin deficiency, though
hyperparathyroidism aluminum toxicity, and increases in inflam-
matory cytokines may contribute.
tests
■Diagnosis based on correlating an inflammatory condition with the
onset of anemia
■Usually a mild normocytic anemia, but microcytosis can be seen.
If additional blood lineages are affected, other diagnoses should be
considered.
■Anemia of hypoproduction, so reticulocyte count should be inap-
propriately low
■Iron tests are most helpful: Low serum iron, high ferritin, low trans-
ferrin and total iron-binding capacity (differentiates from iron defi-
ciency)
■Erythropoietin often elevated, but not elevated in proportion to the
degree of anemia (i.e., lower than the physiological response in sim-
ple iron deficiency). Therefore epo levels are usually lower than “stan-
dard” levels below.
Hbg (g/dl)
in simple iron deficiency Average epo level (mU/mI)
>13 <10
12 15
11 20
10 40
980
8 100
7 200
<6 >1,000differential diagnosis
n/a
management
What to Do First
■Treatment is generally not urgent.
■Determine the underlying disease state. Diagnosis is often one of
exclusion. Ensure other causes of anemia are not present: evaluate
for presence of blood loss and iron deficiency, hemolysis, folate or