Page 605 - Basic _ Clinical Pharmacology ( PDFDrive )

SECTION VI DRUGS USED TO TREAT DISEASES OF THE

BLOOD, INFLAMMATION, & GOUT

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Agents Used in Cytopenias;

Hematopoietic Growth

Factors

*
James L. Zehnder, MD

C ASE STUD Y

A 25-year-old woman who has been on a strict vegan diet women, 37–48%), a hemoglobin concentration of 9.4 g/dL,
for the past 2 years presents with increasing numbness and an erythrocyte mean cell volume (MCV) of 123 fL (nor-
paresthesias in her extremities, generalized weakness, a sore mal, 84–99 fL), an erythrocyte mean cell hemoglobin con-
tongue, and gastrointestinal discomfort. Physical examina- centration (MCHC) of 34% (normal, 31–36%), and a low
tion reveals a pale woman with diminished vibration sen- reticulocyte count. Further laboratory testing reveals a
sation, diminished spinal reflexes, and extensor plantar normal serum folate concentration and a serum vitamin B
12
reflexes (Babinski sign). Examination of her oral cavity (cobalamin) concentration of 98 pg/mL (normal, 250–1100
reveals atrophic glossitis, in which the tongue appears deep pg/mL). Once megaloblastic anemia was identified, why was
red in color and abnormally smooth and shiny due to atro- it important to measure serum concentrations of both folic
phy of the lingual papillae. Laboratory testing reveals a mac- acid and cobalamin? Should this patient be treated with oral
rocytic anemia based on a hematocrit of 30% (normal for or parenteral vitamin B 12 ?

Hematopoiesis, the production from undifferentiated stem blood cells per day in the normal person and even greater numbers
cells of circulating erythrocytes, platelets, and leukocytes, is a of cells in persons with conditions that cause loss or destruction
remarkable process that produces more than 200 billion new of blood cells. The hematopoietic machinery resides primarily
in the bone marrow in adults and requires a constant supply of
* three essential nutrients—iron, vitamin B , and folic acid—as
12
The author acknowledges contributions of the previous author of this
chapter, Susan B. Masters, PhD. well as the presence of hematopoietic growth factors, proteins
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