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Musculoskeletal System Diseases and Disorders 117
Consider This...
common symptoms of musculoskeletal system disorders are pain, immobility, and disability. Diagnosis of a musculoskel
etal system problem is usually made by assessment and X-ray or magnetic resonance imaging. However, other specific
tests such as bone scans or ultrasonography or arthrocentesis also can be used. Although fractures are a major group of
musculoskeletal system disorders, many other diseases are
common to the system. Some of these are short term, but
many are long-term, debilitating disorders. Individuals with
musculoskeletal system diseases frequently need assistive
devices such as crutches or walkers to maintain mobility.
Changes in the musculoskeletal system in older adults often
lead to increased risk for fractures and disability.
Twenty-five percent of your bones are
located in your feet.
Review Questions
Short Answer
1. What are the major functions of the musculoskeletal system?
2. What are the common signs and symptoms associated with musculoskeletal system disorders?
3. What are the most common tests used to diagnose musculoskeletal system disorders?
4. What are two system changes that occur with aging
Fill in the Blank
5. The musculoskeletal system is composed of ______, ____ , ____ , ____, and ____ .
6. ___attach muscle to bone.
7. ___joints are ones that have full movement.
8. ___is the most common disorder of the system.
9. ___is the most serious form of arthritis, but ________is the most common type of arthritis.
118 Chapter 6
Matching
10. Match the fracture-related term in the left column with the appropriate description in the right column.
_____ comminuted a. Bone fragments are in the correct position
_____ nondisplaced b. One bone end is forced over another
_____ transverse c. More than two ends or fragments are present
_____ greenstick d. Bone has protruded through the skin
_____ stress e. An incomplete fracture common in children
_____ impacted f. Fracture runs across or at a 90-degree angle
_____ compound g. Caused by too much weight-bearing or pressure
Case Studies
■ Estella Gore is a 77-year-old resident of a local nursing home. She fell 4 weeks ago and fractured her left
hip and is now in rehabilitation therapy and walking with the assistance of a physical therapy aide and a rolling
walker. She states she is very frightened to walk and would rather use her wheelchair for mobility. She also told
you that she read in a magazine that honey was “good for old bones.” What should you tell Ms. Gore about the
importance of continuing to walk, even if she needs the assistance of a walker or personnel? Why is it important
for her to be as mobile as possible? What are the overall effects of immobility? How does immobility affect other
body systems? Should you talk to her about her statement regarding honey? What could you tell her about it?
■ Jeremy Dale is a 30-year-old recreational sports enthusiast and likes to play soccer and baseball on his
days off from work. He mentions to you, his coworker, that he thinks he might have sprained his ankle over the
weekend while playing soccer with some friends. He says it is swollen and very painful today and asks whether
you think he should see a doctor or just wait for it to get better. What might be some good recommendations
for you to give Jeremy about his sports injury? What could you tell him in general about minor sports injuries?
How could he determine whether this is a sprain or a strain? Should he apply ice and elevate or compress the
injured ankle? Is it too late for that treatment to be helpful?
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7
Blood and Blood
Forming Organs
Diseases and
Disorders
Key Terms
Anemia (p. 122)
Bence Jones protein
(p. 132)
Bleeding time (p. 123)
Complete blood count
(CBC) (p. 122)
Differential (p. 122)
Dyspnea (p. 124)
Ecchymoses (p. 122)
Epistaxis (p. 122)
Erythrocytopenia (p. 122)
Erythrocytosis (p. 122)
Hemarthrosis (p. 132)
Hematemesis (p. 133)
Hematocrit (Hct) (p. 122)
Hematuria (p. 132)
Hemoglobin (Hgb)
(p. 122)
Hemolyzed (p. 124)
Leukemia (p. 129)
Leukocytopenia (p. 122)
Leukocytosis (p. 122)
Lymphopenia (p. 122)
Neutropenia (p. 122)
Pallor (p. 124)
Pancytopenia (p. 128)
Petechiae (p. 122)
Purpura (p. 132)
Reed-Sternberg
cell (p. 130)
Syncope (p. 124)
Tachycardia (p. 124)
Tachypnea (p. 124)
Thrombocytopenia
(p. 122)
Thrombocytosis (p. 122)
Learning Objectives
Upon completion of the chapter, the learner should be able to:
1. Define the terminology common to the blood and
blood-forming organs and the disorders of the
blood and blood-forming organs.
2. Discuss the basic anatomy and physiology of the
blood and blood-forming organs.
3. Identify the important signs and symptoms
associated with common blood and blood
forming organ disorders.
4. Describe the common diagnostics used to
determine the type and cause of blood and blood
forming organ disorders.
Overview
5. Identify the common disorders of the blood and
blood-forming organs.
6. Describe the typical course and management of
the common blood and blood-forming organ
disorders.
7. Describe the effects of aging on the blood and
blood-forming organs and the common disorders
associated with aging of the system.
T
he blood and the blood-forming organs make up the individual’s hematologic system. Blood is the body’s
life fluid, responsible for transporting nutrients to cells and removing wastes. The blood-forming organs
are the lymph nodes, bone marrow, spleen, and liver. Disorders of this system can have severe effects on
119
120 Chapter 7
other systems because of the pervasive responsibilities of the blood and blood-forming organs. Altered
nutrition, medications, and diseases of other systems, in turn, can greatly affect the functioning of the
hematologic system. ■
Anatomy and Physiology
The blood and blood-forming organs are also called
the hematologic system. The major function of the
blood is to transport necessary nutrients to the cells
and to aid in the removal of wastes. The blood also
transports hormones secreted by the endocrine system.
In addition, white blood cells (leukocytes) are import
ant in infection prevention. The blood is composed of a
variety of substances of which plasma, a straw-colored
liquid, makes up about 55% of the total. The formed
elements constitute the other 45%. They include the
erythrocytes (red blood cells, or RBCs), leukocytes
(white blood cells, or WBCs), and platelets (clotting
fragments; Figure 7-1).
Descriptive properties of the blood include its
color, volume, viscosity, and pH. Blood is bright red in
the arteries due to its oxygen content; blood in the veins
is a dark red (often depicted as blue) due to the absence
of oxygen. The average adult has about 75 ml/kg
of body weight of circulating blood (5-6 liters or
approximately 1.5 gallons). The viscosity or density of
blood is about three or more times greater than water.
Blood is slightly alkaline (pH 7.35-7.45).
The erythrocytes transport oxygen from the lungs
to the tissues. The normal erythrocyte count is 4.2 to
6.3 million. Erythrocytes formed in the bone marrow
do not reproduce. Erythrocyte production increases
when oxygen needs increase. During their life span,
which is only about 120 days, red cells become worn
and often ragged from bumping and bouncing into the
vessel walls of the circulatory system. The worn RBCs
are filtered out of circulation by the spleen and the liver.
These organs are responsible for breaking down the
RBCs and saving the iron component for reuse in the
development of new RBCs.
Test tube
containing
whole blood
Leukocytes
Figure 7-1 Blood components.
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Blood and Blood-Forming Organs Diseases and Disorders 121
Consider This...
The average-sized human creates and kills
approximately 15 million blood cells per
second.
Hemoglobin, a component of the RBC, is important
in the transport of oxygen. A low level of hemoglobin in
the blood reduces the level of circulating oxygen. The
normal level of hemoglobin for an adult man is 13.5 to
18 g/100 ml and 12 to 16 g/100 ml for an adult woman.
Leukocytes protect the individual from infec
tions. The average WBC count for an adult is 4,500
to 11,000/mm
3
. A count higher than 11,000 usually
indicates the presence of an infection. See Chapter 4,
“Inflammation and Infection,” and Chapter 5, “Immune
System Diseases and Disorders,” for more information
about leukocytes.
Platelets, also called thrombocytes, produce the
thrombokinase used in the clotting process. The average
number of platelets in adults is 150,000 to 350,000/mm
3
of blood.
The plasma portion of blood is composed of 91%
water and 9% plasma proteins. The plasma proteins
include (a) albumin, responsible for maintaining
osmotic pressure; (b) globulin, responsible for fighting
infection; (c) fibrinogen, responsible for part of the clot
ting process; and (d) prothrombin, also responsible for
part of the clotting process.
Blood coagulation (clotting) occurs in phases. In
the first phase, the platelets, in association with several
plasma proteins, agglutinate (clump) at the site of injury
or blood loss, and thromboplastin is formed. In the
second phase, prothrombin is converted to thrombin
in the presence of calcium. In the third phase, throm
bin and fibrinogen form fibrin. With the presence of
calcium, a fibrin clot is formed. In the fourth phase,
the clot is removed through the process of fibrinolysis.
Blood is classified by the antigens in the RBCs and
the antibodies in the plasma. The antigens are A and B,
and the antibodies are anti-A and anti-B. In addition,
a factor called Rh is used in the classification system.
(See Chapter 5 under “Erythroblastosis Fetalis” and
“Blood Transfusion Reaction” for more information.)
Blood is typed as A, B, AB, and O: Type A blood has A
antigens and anti-B antibodies; type B blood has B anti
gens and anti-A antibodies; type AB blood has A and B
antigens and does not have anti-A or anti-B antibodies;
and type O blood has neither A nor B antigens but has
both anti-A and anti-B antibodies. The Rh designation
is based on 12 distinct antigens. Rh+ blood contains
this antigen, but Rh- blood does not. Because of these
designations and blood properties, blood transfusion
recipients must have a type and a cross-match of blood
to be certain a reaction will not occur (Table 7-1).
The blood-forming organs include the lymph
nodes, bone marrow, spleen, and liver. The lymph
nodes are found throughout the body along the lym
phatic vessels. The lymph nodes filter the lymph and
produce the lymphocytes and antibodies important for
protection from pathogens.
Bone marrow is found in the center part of long
bones and in the spongy part of other bones. It is the
major blood cell-producing organ in the body.
The spleen is found in the upper left quadrant of
the abdomen. It produces lymphocytes, plasma cells,
and antibodies and filters microorganisms from the
blood. It also removes old blood cells from the body.
The liver is a large organ found in the right upper
quadrant of the abdomen. It has multiple responsibil
ities for many body systems. The liver functions as a
blood-forming organ in intrauterine life and is active
the rest of the individual’s life as a producer of pro
thrombin and fibrinogen for blood clotting.
Common Signs and Symptoms
Signs and symptoms of this system include those related
to increases and decreases in the number of blood cells.
Diseases affecting the blood-forming organs (primar
ily spleen, bone marrow, and lymph nodes) can lead to
decreased or increased production of cells. Diseases that
hemolyze, destroy, or use up the cells lead to a decrease
in cell number and volume.
TABLE 7-1 RBC Blood Donor and Recipient Chart
RBC Recipient (Receiver)
O
A B AB
RBC Donor (Giver)
O YES YES YES YES
A NO YES NO YES
B NO NO YES YES
AB NO NO NO YES
YES = This type can receive the donated RBCs.
NO = This type cannot receive the donated RBCs.
122 Chapter 7
Erythrocytopenia (erythron 5 red, cyte 5 cell,
penia 5 decrease) leads to anemia (an 5 without,
emia 5 blood). Anemia does not mean “without any
blood”; it means “low or decreased RBC volume.”
Signs and symptoms of anemia can be minor or major,
asymptomatic to life-threatening, depending on the
cause. Common signs and symptoms include a low
erythrocyte count, headache, fatigue, pallor, and short
ness of breath.
Erythrocytosis (erythrocyte 5 red cell, osis 5 condi
tion of) is a condition of increased RBCs. Common signs
and symptoms include a high RBC count, reddened skin
tones, bloodshot eyes, increased blood volume and pres
sure, and an increase in the workload of the heart.
Leukocytopenia (leuko 5 white, cyte 5 cell,
penia 5 decrease) is a decrease in white cell count.
Leukocytopenia weakens the immune system because
these cells are primary players in the defense system.
Neutropenia (neutrophil decrease) and lymphopenia
(lymphocyte decrease) can be associated with chronic
infection because the numbers are used up during a
long-term battle. Signs and symptoms are related to the
particular type of infection.
Leukocytosis (leukocyte 5 white cell, osis 5 condi
tion of) is an increase in white cell count. This condition
is a normal response to acute infection. If leukocytosis
is related to a tumor, these numbers can be extreme, as
in the case of leukemia (leuk 5 white, emia 5 blood).
Thrombocytopenia (THROM-boh-SIGH-toh-
PEE-nee-ah; thrombocyte 5 platelet, penia 5 decrease)
is a decrease in platelets, leading to a coagulation prob
lem. Signs and symptoms include small hemorrhages
in the skin called petechiae (pee-TEE-kee-eye), large
areas of bruising or hemorrhage called ecchymoses
(ECH-ih-MOH-ses), and epistaxis (EP-ih-STACK-sis;
nosebleeds). Bleeding lesions in the mouth, gums, and
mucous membranes are also common.
Thrombocytosis (THROM-boh-sigh-TOE-sis;
thrombocyte 5 platelet, osis 5 condition of) is an
increase in platelets. This condition is uncommon and
usually has no serious side effects (Table 7-2).
Diagnostic Tests
Diagnostic tests for blood and blood-forming organ dis
orders include complete blood count with differential
and indices. Biopsy of the blood-forming organs also
can be helpful in diagnosing disorders of the spleen,
lymph nodes, and bone marrow.
A complete blood count (CBC) identifies the num
ber of RBCs, WBCs, and platelets per cubic millimeter
(Table 7-3) and can be used in the determination of
most blood diseases. RBC count and indices can assist in
the determination of the different anemias, polycythe
mia, and erythrocytosis. A differential is a more detailed
count, identifying the number of each type of leukocyte.
A WBC count and differential can assist in determining
inflammation and infection or tumors of white cells.
Hematocrit (Hct) reflects the amount of red cell mass
as a proportion of whole blood. Hemoglobin (Hgb)
reflects the amount of hemoglobin or oxygen-carrying
potential available in the blood. Special measurements
of red cells are called indices and include
■ MCV Mean corpuscular volume; reflects the average
size of the red cell
■ MCH Mean corpuscular hemoglobin, or average
hemoglobin content
■ MCHC Mean corpuscular hemoglobin concentra
tion, or average hemoglobin concentration
TABLE 7-2 Blood Cell Abnormalities and Associated Symptoms
Condition
Symptoms
Red Blood Cells
Increased Erythrocytosis Reddened skin, increased blood pressure, increased workload on the heart
Decreased Erythro cytop enia Anemia
White Blood Cells
Increased Leukocytosis Usually asymptomatic
Decreased Leukocytopenia Weakened immune system
Thrombocytes
Increased Thrombocytosis Increased clotting
Decreased Thrombocytopenia Increased bleeding
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Blood and Blood-Forming Organs Diseases and Disorders 123
TABLE 7-3 CBC Normal Values
Cells Values
Erythrocytes Males
4.6-6.3 million/mm
3
Females
4.2-5.4 million/mm
3
Hematocrit Males
40-54%
Females
38-47%
Hemoglobin Males
13-18 g/dl
Females
12-16 g/dl
RBC indices
MCV 80-96 mm
3
MCH
27-31 pg
MCHC 32-36%
Leukocytes
Differential
4,300-11,000 mm
3
Myelocytes 0/mm
3
Band neutrophils 1,500-3,000/mm
3
Segmented neutrophils 300-500/mm
3
Lymphocytes 50-250/mm
3
Monocytes 15-50/mm
3
Eosinophils 15-50/mm
3
Basophils 15-50/mm
3
Platelets 150,000-350,000/mm
3
Reticulocytes 25,000-75,000/mm
3
Key: g/dl = grams per deciliter; MCH = mean
corpuscular hemoglobin concentration; MCV =
millimeter; pg = picograms.
corpuscular hemoglobin; MCHC = mean
mean corpuscular volume; mm
3
= cubic
The morphology of each of the cells and platelets
can be observed by performing a blood smear. A blood
smear is performed by placing a drop of blood on a glass
slide, smearing it to spread the cells to a thin layer, and
staining and examining it microscopically for abnor
mal cell morphology or shape. Adding a staining solu
tion to the slide helps in the identification of granular
and agranular WBCs. A blood smear can be helpful in
determining the cause of anemia, especially sickle cell
disease.
A bleeding time is used to measure the time it takes
the blood to clot. It can assist in determining blood
disorders such as hemophilia, thrombocytopenia,
or disseminated intravascular coagulation, and liver
disease, vitamin K deficiency, or defective clotting
factors. Prothrombin time (PT) and partial throm
boplastin time (PTT) are often used in conjunction
to evaluate both the clotting time and the function
of the coagulation factors. The international normal
ized ratio (INR) is also used to measure bleeding time.
It is most often used to monitor the effectiveness of
anticlotting medications such as warfarin. It measures
the time it takes for blood to clot and compares it to
an average.
Biopsy of blood-forming organs can be helpful in
diagnosing diseases and disorders. For instance, bone
marrow biopsy is performed by boring a needle into
the bone of the iliac crest of the hip to obtain tissue that
is prepared and microscopically examined. A lymph
node biopsy can be performed to determine the func
tioning of the marrow, detect anemias, and diagnose
neoplasms.
Common Diseases of the Blood
and Blood-Forming Organs
The most common problem related to this system is
anemia, a decrease in RBC mass that can be caused
by a number of different disease processes. Anemia is
generally a sign of a disease but is commonly used as
a diagnosis until the cause is discovered. Anemia can
be serious if the cause is not determined or cannot be
corrected.
Disorders of WBCs are usually secondary to other
diseases rather than as a primary disease. Infections
demand an increased need for WBCs because they are
used up while fighting the invader. This can lead to leu-
kocytopenia, a decrease in WBC number.
Any disorders of the blood-forming organs
(spleen, bone marrow, lymph nodes) can lead to sec
ondary disorders of this system. Leukemias, lympho
mas, and myelomas are the primary tumors affecting
the system.
Disorders of Red Blood Cells
Any increase or decrease in the number or size of RBCs
will affect the mass or volume. Red cell mass is import
ant because it directly affects the amount of hemoglobin
available (oxygen-carrying potential). Commonly, the
problem is not enough red cell mass, leading to ane
mia. Too much red cell mass is called erythrocytosis,
the most common type of which is a condition called
polycythemia.
124 Chapter 7
Pharmacology
Highlight
Common Drugs for Blood and Blood-Formin
g Disorders
Category Examples of Medications
Anticoagulants and Plasminogen Activators
Drugs used to prevent
clotting or break up a clot
Alteplase, anistreplase, dabigatran, heparin,
tenecteplase, or warfarin (Some of these are not
used for an acute stroke.)
Antineoplastics
Drugs used to treat cancer
Alkylating agents
Antimetabolites
Chlorambucil, cyclophosphamide, or lomustine
5-Flourauracil, clofarabine, mercaptopurine, or
methotrexate
Antitumor antibiotics
Hormones/antihormones
Other substances
Doxorubicin, mitomycin or streptozocin
Estrogens, androgens, flutamide, or tamoxifen
Vincristine, l-asparaginase, paclitaxel, carboplatin,
cisplatin, desatinib, etoposide, imatinib, indarubicin,
nilotinib, ponatinib
Vitamins/Minerals
Supplements used to support
or replace low levels
Calcium, chromium, folate, iodine, iron,
magnesium, selenium, vitamins A, B6, B
12
, C, D, E,
K, or zinc; these may be prescribed individually or
in combinations
Consider This...
It takes a red blood cell 20 seconds to cir
culate through the entire body.
Anemia
■ Description. Any decrease in oxygen-carrying ability
of the RBC is anemia. There are more than 400 types
of anemia; the three most common types are related to
deficiency of iron, folic acid, and vitamin B
12
.
■ Etiology. Anemia is commonly due to a low number
of RBCs or a decrease in hemoglobin in RBCs. Acute
hemorrhage or chronic bleeding can lead to a low num
ber of circulating RBCs and, thus, anemia.
Any disease of the liver, spleen, or bone mar
row can also lead to anemia. For instance, if the
cells are broken down (hemolyzed) too soon, this
can lead to a decrease in cell number; if cells are not
formed quickly enough to replace the worn cells, the
number of circulating cells will be low. If cells are
formed abnormally, their ability to carry oxygen can
be impaired because although the number of cells
might be adequate, their oxygen-carrying ability is
not. Dietary deficiencies often lead to an inadequate
supply of nutrients to make RBCs.
■ Symptoms. Despite the cause, the symptoms of ane
mia are fairly common. The individual suffering from
anemia commonly is pale or has a condition of pallor.
Facial paleness can be difficult to determine, but further
examination of the mucous membranes of the mouth
and conjunctiva of the eyes will reveal definite paleness.
The nail beds also might be noticeably pale in color.
Anemic individuals are weak and suffer from
fatigue due to poor oxygenation of muscle tissue. Short
ness of breath, dyspnea (DISP-nee-ah; dys 5 difficult,
pnea 5 breathing), tachycardia (TACH-ee-KAR-
dee-ah; tachy 5 fast, cardia 5 heart), and tachypnea
(TACK-ip-NEE-ah; tachy 5 fast, pnea 5 breathing) are
common as the heart and lungs attempt to meet the
body’s oxygen need. Headache, irritability, and syncope
(SIN-koh-pee; fainting) can also be symptoms.
■ Diagnosis. Anemia can be very simple or related to a
complicated or chronic disease. For simple cases, a his
tory and physical examination along with blood tests
measuring the level of hemoglobin, hematocrit, iron,
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Blood and Blood-Forming Organs Diseases and Disorders 125
folic acid, and vitamin B
12
assist in diagnosis. Micro
scopic examination of the size and shape of the red
cells also provides further clues to the type of anemia.
More complicated anemias, or those caused by
chronic disease, might need further testing, including
urine analysis, stool sampling, endoscopy, colonoscopy,
and bone marrow biopsy.
■ Treatment. Determining the cause of anemia is very
important because treatment is directed at the cause.
Therefore, treatment for anemia varies, depending on
the cause or type of anemia. Some anemias can be cured,
whereas others, such as sickle cell anemia, are not curable.
■ Prevention. Eating a healthy diet including foods
high in iron and B complex vitamins will prevent defi
ciency anemias. More complicated types might not be
preventable or treatable.
Iron Deficiency Anemia
■ Description. Iron deficiency anemia arises when
there is insufficient iron for the body to produce the
oxygen-carrying component, hemoglobin, within
RBCs.
■ Etiology. Iron deficiency anemia can be due to a loss
of iron, such as from chronic blood loss, or to an inad
equate intake of iron such as from low dietary intake
of iron. Chronic blood loss can be due to bleeding
hemorrhoids, gastrointestinal bleeding, and heavy or
prolonged menstrual flow. Iron deficiency anemia is
commonly seen in females during times of increased
iron demand as occurs during pregnancy and breast
feeding. During their menstrual years, females often
have iron loss due to a combination of menstruation
and inadequate dietary intake of iron.
■ Symptoms. Symptoms previously described in the
anemia section pertain here as well but, briefly, include
pallor, weakness, fatigue, and dyspnea.
■ Diagnosis. A history and physical examination, along
with blood tests indicating low levels of hemoglobin,
iron, or both, assist in diagnosing an iron deficiency. For
cases caused by bleeding, further tests include looking
for the presence of blood in urine and stool samples.
Gastroscopy and colonoscopy also can help determine
the origin of the bleeding.
■ Treatment. Treatment is aimed at the cause and can
include resolving a bleeding problem or increasing
dietary intake of iron (foods high in iron are listed in the
Healthy Highlight box “Increasing Iron in the Diet”).
Iron supplements like ferrous sulfate may also be pre
scribed. With treatment, iron levels are usually restored
to normal within 2 months.
■ Prevention. Iron deficiency anemia can be prevented
by eating a healthy diet high in iron. Anemia related to
blood loss can be prevented by seeking medical help at
the first sign of excessive bleeding.
Folic Acid Deficiency Anemia
■ Description. Folic acid is a B complex vitamin neces
sary for the maturation of RBCs. A deficiency in folic
acid leads to this type of anemia.
■ Etiology. Deficiency of folic acid can be related to poor
diet, overcooking vegetables, or alcoholism. Deficiency
can also occur during times of high folic acid need such
as those associated with infancy and pregnancy.
■ Symptoms. Symptoms can include fatigue, weight loss,
abdominal pain, black or bloody stools, and chest pain.
Healthy Highlight
Increasing Iron
in the Diet
I
ndividuals with iron deficiency anemia may be able to correct the disorder by just
eating well-balanced meals as opposed to taking iron supplements for the deficiency.
Heme and nonheme are the two forms of dietary iron. Heme is found in animal foods,
while nonheme is found in the plant foods. Individuals who are vegetarian can increase
their iron intake by eating more legumes, nuts, and greens. Twelve foods rich in iron
content include shellfish, spinach, liver and other organ meats, legumes, red meat,
pumpkin seeds, quinoa, turkey, broccoli, tofu, dark chocolate, and fish. Also, consum
ing vitamin C-rich foods assists in the absorption of nonheme iron.
Source: Bell (2020)
126 Chapter 7
■ Diagnosis. Blood testing aids in the diagnosis. A CBC
will show anemia and abnormally large RBCs. The blood
folate level will also be low. Bone marrow biopsy is seldom
needed but also will show abnormally large red cell size.
■ Treatment. Treatment is aimed at increasing dietary
intake of foods high in folic acid, such as green leafy
vegetables, mushrooms, lima beans, and kidney beans.
Folic acid supplements may also be prescribed. If there
are no complications to treatment, folic acid levels are
usually restored to normal within 2 months.
■ Prevention. Consumption of a diet high in folic acid
aids in prevention.
Vitamin B
12
Deficiency Anemia
■ Description. Vitamin B
12
anemia results from a dietary
deficiency in B
12
or an inability of the digestive tract to
absorb it. Vitamin B
12
is essential for the body to produce
RBCs as well as to maintain a healthy nervous system.
■ Etiology. Inability to absorb B
12
can be due to sev
eral factors, including (a) removal of the small intestine,
where B
12
is absorbed; (b) having a disease that affects
the small intestine, such as Crohn’s disease, which inter
feres with absorption; (c) consumption of a diet defi
cient in B
12
; or (d) loss or lack of intrinsic factor. This
last cause of deficiency is the most common and is also
called pernicious anemia.
Pernicious Anemia
Pernicious anemia usually affects older individuals
and has an unusual cause. The mucosa, or lining, of
the stomach normally secretes a protein called intrinsic
factor. This factor is necessary for vitamin B
12
absorp
tion in the small intestine. Those affected have had an
autoimmune disorder (a disorder caused by the per
son’s own immune system) that blocks production or
destroys the cells that produce this intrinsic factor.
■ Symptoms. Common symptoms include pallor,
fatigue, weakness, confusion, depression, and numbness
in the hands and feet.
■ Diagnosis. Vitamin B
12
deficiencies are diagnosed by
a thorough history and physical, CBC, and blood testing
for vitamin B
12
. A history of small-intestine surgery or
chronic disease of the small intestine can be recognized
easily and diagnosed. Dietary deficiency and pernicious
anemia can be more difficult to diagnose and might
need further testing, including a gastroscopy (looking
through a scope into the stomach) to view the cells that
produce intrinsic factor.
■ Treatment. Treatment depends on the cause of
the deficiency. Absorption and dietary deficiency ane
mia can be treated with oral vitamin tablets, inject
able vitamin B
12
, or consumption of a diet high in
vitamin B
12
. Meat, fish, poultry, and milk are all sources
of B
12
. Pernicious anemia cannot be treated with a
change in diet because without an intrinsic factor, no
amount of B
12
can be absorbed. Treatment is a monthly
injection of vitamin B
12
for the life of the individual.
■ Prevention. Anemias related to poor diet can be pre
vented by eating a diet high in vitamin B
12
. At this time,
pernicious anemia is not preventable.
Hemolytic Anemia
■ Description. Hemolytic anemia is characterized by
increased destruction of RBCs.
■ Etiology. This type of anemia can be related to an
antigen-antibody reaction as with Rh factor in blood
transfusion reaction or erythroblastosis fetalis. (See
Chapter 5 for detailed information.) Hemolytic anemia
also can occur due to a disorder of the immune system
leading to the destruction of one’s own erythrocytes.
This type of anemia can be severe and can lead to death
of the individual. Hemolytic anemia can be brought on
by exposure to chemicals such as benzene; medications,
including aspirin and penicillin; and bacterial toxins.
■ Symptoms. Symptoms include pallor, weakness,
fatigue, and tachycardia, the last of which can lead to
heart failure.
■ Diagnosis. A thorough history and physical along
with blood testing will aid in diagnosis. CBC will reveal
anemia. A blood smear will reveal an increased number
of immature and fragmented red cells.
■ Treatment. Treatment can include prompt exchange
transfusion (removing the individual’s blood and replac
ing it with donor blood). Steroid medication along with
splenectomy can also help. Folic acid and iron supple
ments may also be prescribed.
■ Prevention. Hemolytic anemia due to genetic inher
itance is not preventable. Acquired hemolytic anemias
such as transfusion reactions can be prevented with
proper screening.
Sickle Cell Anemia
■ Description. Sickle cell anemia is a hereditary anemia
found in Blacks that causes an abnormal sickle shape
of the erythrocyte. Interestingly, sickle cell disease is
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