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| What is blood? |
| Blood is a living tissue that circulates through the heart, arteries
and veins and organs carrying nourishment, electrolytes, hormones,
vitamins, antibodies, heat and oxygen to the body's tissues. |
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| What is whole blood? |
| Whole blood is just as it sounds-it is blood with all of its
components intact. Whole blood contains red blood cells, white blood
cells and platelets suspended in a proteinaceous fluid called plasma.
These parts can be separated from whole blood in order to provide
patients with superior treatment by giving them the specific elements
they need. It also eliminates waste by excluding non-essential components
for each particular treatment. Whole blood donations can be made
every 12 weeks (3 months). |
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| What are red blood cells? |
| Red blood cells are perhaps the most recognizable component of
whole blood. Red blood cells contain hemoglobin, a complex iron-containing
protein that carries oxygen throughout the body and gives blood
its red color. The percentage of blood volume composed of red blood
cells is called the hematocrit. The average hematocrit in an adult
male is 47 percent. Manufactured in the bone marrow, red blood cells
are continuously being produced and broken down. They live for approximately
120 days in the circulatory system and are eventually removed by
the spleen. Red blood cells are prepared from whole blood by removing
the plasma, or the liquid portion of the blood, and can raise the
patient's hematocrit and hemoglobin levels while minimizing an increase
in blood volume. |
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| How are red blood cells used? |
| Patients who benefit most from transfusions of red blood cells
include those with chronic anemia resulting from disorders such
as kidney failure, malignancies, or gastrointestinal bleeding and
those with acute blood loss resulting from trauma or surgery. Since
red blood cells have reduced amounts of plasma, they are well-suited
for treating anemia patients who would not tolerate the increased
volume provided by whole blood, such as patients with congestive
heart failure or those who are elderly or debilitated. |
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| What is plasma? |
| Plasma is the liquid portion of the blood--a protein-salt solution
in which red and white blood cells and platelets are suspended.
Plasma, which is 90 percent water, constitutes about 55 percent
of blood volume. Plasma contains albumin (the chief protein constituent),
fibrinogen (responsible, in part, for the clotting of blood), globulins
(including antibodies) and other clotting proteins. Plasma serves
a variety of functions, from maintaining a satisfactory blood pressure
and volume to supplying critical proteins for blood clotting and
immunity. It also serves as the medium of exchange for vital minerals
such as sodium and potassium, thus helping maintain a proper balance
in the body, which is critical to cell function. Plasma is obtained
by separating the liquid portion of blood from the cells. Fresh
frozen plasma is frozen within hours after donation to preserve
clotting factors, stored for one year, and thawed before it is transfused.
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| How is plasma used? |
| Plasma is most often used to treat certain bleeding disorders
when a clotting factor or multiple factors are deficient and no
factor-specific concentrate is available. It can also be used for
plasma replacement via a process called plasma exchange. |
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| What are platelets? |
| Platelets (or thrombocytes) are very small cellular components
of blood that help the clotting process by sticking to the lining
of blood vessels (basically, they form scabs). Platelets are made
in the bone marrow and survive in the circulatory system for an
average of 9-10 days before being removed from the body by the spleen.
The platelet is vital to life, because it helps prevent both massive
blood loss resulting from trauma and blood vessel leakage that would
otherwise occur in the course of normal, day-to-day activity. Units
of platelets are prepared by using a centrifuge to separate the
platelet-rich plasma from the donated unit of whole blood. The platelet-rich
plasma is then centrifuged again to concentrate the platelets further.
Platelets may also be obtained from a donor by a process known as
apheresis, or plateletpheresis. In this process, blood is drawn
from the donor into an apheresis instrument, which, using centrifugation,
separates the blood into its components, retains the platelets,
and returns the remainder of the blood to the donor. The resulting
component contains about six times as many platelets as a unit of
platelets obtained from whole blood. Platelets are stored at room
temperature for up to five days. Blood Facts Menu l FAQ Menu |
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| How are platelets used? |
| Platelets are used to treat a condition called thrombocytopenia,
in which there is a shortage of platelets, and to prevent bleeding
in patients with abnormal platelet function. |
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| What are white blood cells? |
| White blood cells are responsible for protecting the body from
invasion by foreign substances such as bacteria, fungi and viruses.
The majority of white blood cells are produced in the bone marrow,
where they outnumber red blood cells by two to one. However, in
the blood stream, there are about 600 red blood cells for every
white blood cell. There are several types of white blood cells.
Granulocytes and macrophages protect against infection by surrounding
and destroying invading bacteria and viruses, and lymphocytes aid
in the immune defense. Granulocytes can be collected by apheresis
or by centrifugation of whole blood and are transfused within 24
hours after collection. |
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| How are white blood cells used? |
| White blood cells are used to fight infections that are unresponsive
to antibiotic therapy and to produce interferon. The effectiveness
of white blood cell transfusion is still being investigated. |
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| What is Apheresis? (Under
Process for FDA Approval) |
| An increasingly common procedure is apheresis, or the process
of removing a specific component of the blood, such as platelets,
and returning the remaining components, such as red blood cells
and plasma, to the donor. This process allows more of one particular
part of the blood to be collected than could be separated from a
unit of whole blood. Apheresis is also performed to collect plasma
(liquid part of the blood) and granulocytes (white blood cells).
The apheresis donation procedure takes longer than whole blood donation.
A Whole Blood donation takes about 10-20 minutes to collect the
blood, while an apheresis donation may take about 90 minutes. The
benefits of an apheresis donation are plentiful. Not only can an
apheresis donor produce a higher volume of a specified blood component
when they donate, they can donate more often-as many as 24 times
per year for platelets and 12 times per year for plasma. |
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| Who Needs Apheresis Products? |
| Patients with cancer or leukemia, transplant recipients and patients
with blood disorders need apheresis products. Chemotherapy and radiation
treatment destroy healthy cells and platelets are needed to prevent
bleeding. |
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| What is our blood volume? |
| The blood volume in a healthy adult amounts to 8% of total body
weight. For example, if you weigh 100 lbs., 8 lbs of blood is circulating
in your body. |
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| How much blood do we have? |
| An average size female has about nine pints of blood, while an
average size male has about 12 pints of blood. |
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| How does the body make blood? |
| Red cells, platelets and white cells are made in the bone marrow.
Coagulation proteins (clotting factors) are made in the liver and
water comes from the body's general fluid content. |
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| What is bone marrow? |
| Marrow is a substance found inside bones. It resembles blood
and contains stem cells, which produce red blood cells, white blood
cells and other blood components important for fighting infection,
carrying oxygen and helping to control bleeding. Stem cells, the
cells that transplant patients need to make new healthy marrow,
usually live in bone marrow, but are also released, in small numbers,
into the circulating (peripheral) blood. There are several treatments
that will dramatically increase the release of stem cells into the
circulating blood so that enough stem cells for transplant can be
collected directly from the bloodstream. |
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| How long can we store blood? |
| Red blood cells can be stored for up to 35 days at
1-6°C. Platelets must be kept at room temperature and expire in
5 days. Fresh frozen plasma and CRYO must be stored at -18°C for
no longer than 1 year. |
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| What is blood type? |
| There are four groups of blood, the A group, the
B group, the AB group and the O Group. All of these groups can either
be Rh negative or Rh positive, thus producing the eight basic types
of blood. Your Blood type is inherited from your parents and does
not change. |
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| How do they determine blood type? |
Forward typing:
If your blood clots when it is mixed with anti-A serum, then you
have type A blood.
If your blood clots when mixed with anti-B serum, then you have
type B blood.
If your blood clots when it is mixed with both anti-A and anti-B
serums, then you have type AB blood.
If your blood does not clot in the presence of either serum, then
you have type O blood.
If your blood clots when mixed with anti-Rh serum, then you have
type Rh-positive blood.
If your blood does not clot when mixed with anti-Rh serum, then
you have type Rh-negative blood.
Reverse typing:
Clotting that occurs when B cells are mixed with your serum indicates
you have type A blood.
Clotting that occurs when A cells are mixed with your serum indicates
you have type B blood.
Clotting that occurs when your serum is mixed with both types of
cells indicates you have type O blood.
Lack of clotting when your serum is mixed with both types of blood
indicates you have type AB blood. |
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| What is the most common type of blood? |
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Blood
Type
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Percent
of Indian Population
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| O Rh-positive |
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| O Rh-negative |
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| A Rh-positive |
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| A Rh-negative |
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| B Rh-positive |
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| B Rh-negative |
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| AB Rh-positive |
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| AB Rh-negative |
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| What blood types are compatible? |
The rules of blood transfusion are as follows. Any
patient who is Rh-negative must receive Rh-negative blood. Patients
who are Rh-positives (Rh) can receive Rh-negative or Rh-positive
blood. Patients with group O must get group O. Patients with group
AB can recieve any group. O Negatives are "Universal Donors" while
AB Positives are "Universal Recipients." The following chart will
help to illustrate compatibility.
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Patient
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Compaitible
Donor(s)
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| O+ |
O +, O - |
| O- |
O- |
| A+ |
A+, A-, O+, O-
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| A- |
A-, O- |
| B+ |
B+, B-, O+, O-
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| B- |
B-, O- |
| AB+ |
AB+, AB-, A+,
A-, B+, B-, O+, O- |
| AB- |
AB-, A-, B-, O-
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| What is blood tested for? |
Every pint of blood collected by the INDU's
Blood Centers undergoes 18 hours of processing, testing and labeling.
During this testing, every pint goes through 10 screening tests
before being transfused. Blood drawn is usually transfused within
36 hours of collection. After blood is drawn, it is tested for ABO
group (blood type) and Rh type (positive or negative), as well as
for any unexpected red blood cell antibodies that may cause problems
for the recipient. Screening tests performed are listed below:
- Hemoglobin
- Blood group and Rh type
- Blood group antibody screening
- Serological test for syphilis
- Hepatitis B surface antigen
- HIV 1/2 antibody (AIDS)
- Hepatitis C virus antibody
- Malarial Parasite |
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| What is autologous donation? |
Blood donated by an individual for his or her exclusive
use is referred to as an autologous or self-donation. The primary
advantage of autologous donations is simple: your own blood is an
exact blood match with no crossmatching issues.
INDU's Blood Centers provides both
short-term and long-term blood storage. Short-term donated blood
is kept refrigerated (maximum of 42 days) while long-term blood
is frozen (up to 10 years).
Individuals preparing for elective surgery are primary candidates
for autologous donations. In this case, the individual's physician
must sign a request for the autologous donation procedure, which
may allow the person to donate as frequently as every two weeks.
The donated blood will then be stored in liquid form and be delivered
to the hospital for use during the patient's surgery.
Long-term frozen storage enables a donor to build up a reserve of
their blood over time. Because of the length of time to thaw and
process frozen blood, it is not suitable for emergency situations.
Frozen blood storage requires special care and monthly storage charges,
which can be costly for donors. People with reoccurring ailments
such as bleeding ulcers are good candidates for long term frozen
storage.
Recent data indicate that autologous blood accounts for 4.6 percent
of all donated blood. Almost half of all autologous donations are
not used by the donor, and many of these units are discarded because
this autologous blood may not be suitable for transfusion to another
patient.
A written order from the patient's physician is required prior to
autologous blood collection. |
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| What is a directed donation? (Replacement) |
| Donating for someone specific is termed a directed
donation. Directed donations occur when a family member or close
friend with compatible blood is asked to donate for someone having
elective or scheduled surgery. The same screening and tests are
required as a regular donation. If the blood is not used by the
person it was designated for, it CAN be returned to the regular
inventory. |
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| How is blood used? |
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Recipients
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Blood
Needed
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| Accident Victims |
Anywhere from four to more than 100 units, depending
on the injury. People who have been in a car accident or suffered
mass blood loss need an average of 50 pints of blood. |
| Cancer Patients |
Need blood and blood products on an ongoing
basis while they undergo chemotherapy and/or radiation. Ten
donors are needed for one pool of platelets, the most common
blood product used in cancer treatment. Each patient can need
one to two pools of platelets per week. |
| Open Heart Surgery |
Uses an average of six pints of red blood cells
and six units of platelets. |
| Neurosurgery (spinal/brain surgery) |
Uses two to four units of red cells. |
| Premature Babies |
One donation can transfuse four babies, who
often use blood once a day until they are strong enough to
go home. |
| Burn Victims |
Severe cases can need 20 units of platelets
during treatment |
| Bone Marrow Transplant |
Average transplant requires 120 units of platelets
and about 20 units of red blood cells. |
| Sickle-Cell Anemia |
Some patients with complications from this disease
receive blood transfusions every month. |
| Liver Transplants |
Average patient needs 40 pints of red blood
cells, 30 pints of platelets, 20 bags of cryoprecipitate and
25 pints of plasma. |
| Orthopedics (hip replacement or surgery) |
Between two and eight units. |
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| Donor Pathways (Personality
Trust) |
Each of the four main blood types, A, B, AB and O
have characteristics that lend themselves to certain uses. The following
is a basic list of these uses:
Type O
Type O is the Universal Donor, meaning anybody can use your
blood. Your blood is needed for trauma and emergency patients who
need blood immediately and can't wait to be typed. Be an ER lifesaver!
Donate every eight weeks.
Type A
Type A is the second most common blood type; so many trauma
patients will need your blood. Your blood is most valuable when
donating platelets that are given to cancer patients undergoing
chemotherapy. You can help a cancer victim! Platelet donors can
give every two weeks.
Type B
Type B is a somewhat rare and often needed blood type. Your
blood is used to treat trauma patients and children with sickle
cell anemia. Give a child a second chance! Donate every eight weeks.
Type AB
Type AB is the universal plasma donor. Your blood is most valuable
when giving plasma because it can be given to patients with any
blood type. Your plasma is most commonly used for burn patients,
patients requiring massive transfusions and patients with bleeding
disorders. Provide someone a lifeline! Plasma donors should donate
every four weeks.
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| What is anemia? |
Anemias are conditions in which the number of red
blood cells or amount of hemoglobin (the protein that carries oxygen)
in them is below normal. If you have anemia, you cannot donate blood.
Red blood cells contain hemoglobin, which enables them to carry
oxygen from the lungs and deliver it to all parts of the body. Because
anemia reduces the number of red blood cells or the amount of hemoglobin
in them, the blood can't carry an adequate supply of oxygen. Symptoms,
caused by the inadequate oxygen supply, are varied. For example,
anemia can cause fatigue, weakness, inability to exercise, and light-headedness.
Simple blood tests can identify anemia. The percentage of red blood
cells in the total volume of blood (hematocrit) and the amount of
hemoglobin in a blood sample can be determined. These tests are
part of the complete blood cell count (CBC).
Many nutrients are needed for red blood cell production. The most
critical are iron, vitamin B12, and folic acid, but the body also
needs trace quantities of vitamin C, riboflavin, and copper, as
well as a proper balance of hormones, especially erythropoietin
(a hormone that stimulates red blood cell production). |
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| What foods will help correct my anemia? |
Anemia is often a temporary condition that can be
corrected with diet. Through a change in diet, many of the aforementioned
nutrients can be replaced.
The best sources for iron: Iron fortified cereals and liver
(chicken, beef or pork).
Good sources of Iron: Lean meat, greens (turnips, mustard,
collard, spinach), liverwurst, oysters, clams, prunes (prune juice),
raisins, dried apricots, dried peaches, dried beans and green lima
beans.
Fair sources of Iron: Eggs, enriched cereals, enriched bread,
blackberries, strawberries, watermelon, black-eyed peas and green
peas.
Vitamin C is needed by your body to help you use the iron you eat.
The best sources for Vitamin C: 0ranges (orange juice), grapefruits
(grapefruit juice), tomatoes (tomato juice), greens, broccoli, watermelon,
raw cabbage, cantaloupe and strawberries. |
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| What is Sickle Cell Anemia? |
Sickle cell disease is an inherited condition that
is most common among people whose ancestors come from Africa, the
Middle East, the Mediterranean basin, and India. In the U.S., it
affects primarily African Americans, about 0.3% of whom have some
form of sickle cell disease, and approximately 10% of whom carry
the sickle cell trait. There are approximately 80,000 individuals
in the United States with sickle cell disease.
The red blood cells of people with sickle cell disease contain an
abnormal type of hemoglobin, the oxygen-carrying pigment, called
hemoglobin S. The deficiency of oxygen in the blood causes hemoglobin
S to crystallize, distorting the red blood cells into a sickle shape,
making them fragile and easily destroyed, leading to anemia.
The "sickled" blood cells then are unable to squeeze through the
smaller blood vessels (arterioles and capillaries). When the tissues
are deprived of an adequate blood supply, painful symptoms occur.
Complications can include stroke, bone pain, kidney damage and breathing
problems. The recurrent pain caused by the disease can interfere
with many aspects of the patients' lives including education, employment,
and psychosocial development.
Normal Hemoglobin & Sickle Hemoglobin While sickle hemoglobin
and normal hemoglobin carry the same amount of oxygen, two major
differences exist between the two kinds of cells. First, they differ
in the way they flow through the blood vessels. Normal hemoglobin
is found in disc-shaped red blood cells that are soft (like a bag
of jelly), which enables them to easily flow through small blood
vessels. Diseased red blood cells which are sickle-shaped and are
hard (like pieces of wood), often get stuck in small blood vessels
and stop the flow of blood.
The second difference between the two types of cells is their longevity.
Sickle cells do not live as long as normal cells. Normal, healthy
cells can survive for about 120 days, while the more fragile sickle
cells can survive for about 60 days or less. Unfortunately, the
body cannot make new red blood cells as fast as it loses sickle
blood cells. As a result, a sickle cell patient has fewer red blood
cells and less hemoglobin than normal red blood cells. This decreased
hemoglobin (called anemia), in turn, results in less oxygen being
available for use by the cells of the body.
Three normal red blood cells and one "sickled" cell.
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How Do You Get Sickle Cell Disease?
The only way you can get sickle cell disease is by genetic inheritance.
You cannot get sickle cell disease by contact or by blood transfusions.
There are many forms of sickle cell disease. These occur whenever
the gene for abnormal hemoglobin S combines with any other gene
for abnormal hemoglobin, (e.g., C, O, E, Beta-Thalassemia, etc.).
The resulting types of sickle cell disease in the above examples
would be SC, SO SE, and S Beta-Thalassemia, respectively. However,
when one hemoglobin S gene combines with a second hemoglobin S gene,
the result is a particular type of sickle cell disease known as
sickle cell anemia, or SS disease. This is probably the most well
known form of sickle cell. Even though we often see the term sickle
cell anemia used to refer to all types of sickle cell disease, technically,
SS disease is the only form of sickle cell disease that is correctly
referred to as sickle cell anemia. The umbrella term, "sickle cell
disease" does, however, refer to any of the above conditions.
As sickle cell is a genetic disorder, in order to have sickle cell
disease, you must inherit a hemoglobin S gene. Inheriting the hemoglobin
S gene from only one parent and a normal hemoglobin gene from the
other parent means you only have the trait, and not the disease.
Anyone who has the trait has the potential for passing it on to
his or her child.
Sickle Cell Disease & Sickle Cell Trait
People who have inherited a hemoglobin S gene from one parent and
a second abnormal hemoglobin gene from the other parent manifest
symptoms of sickle cell disease by having sickled cells in the bloodstream.
People with sickle cell trait usually do not manifest any of the
problems associated with sickle cell disease. However, there have
been cases that show people with sickle cell trait can exhibit sickle
cells under extreme conditions of physical stress or low atmospheric
oxygen.
More of What Happens When You Have Sickle Cell Disease
Clogged blood capillaries can lead to different types of problems,
depending upon where the blockage occurs. The outcome of this blockage
may lead to problems such as kidney infections; intense pain in
the chest, arms and legs; death and decay of tissues, especially
in the joints; disease of the retina of the eye; slow healing sores
or ulcers; gallstones; and cerebral vascular accidents, or "strokes."
The health problem known as anemia may result because the sickle
cell does not last as long as the normal red blood cell. Normal
red blood cells last 120 days; sickle cells last, at the most, 60
days. This shorter lifespan means fewer circulating red blood cells
and, therefore, a smaller amount of hemoglobin at any given time
compared to normal. Low hemoglobin (anemia) is manifested as fatigue
and weakness.
Is There A Cure?
Presently, there is no cure for sickle cell disease. However, there
is treatment for the pain and other aspects of the disease. Pain
medication, antibiotics, rest, good nutrition, supplementation with
folic acid and high fluid intake are all helpful treatments for
aspects of sickle cell disease. At times, invasive procedures such
as blood transfusions and surgery may be needed. Recently, treatment
with hydroxyurea has been shown to increase the production of fetal
hemoglobin, which does not sickle like normal sickle cells. Other
experimental drugs are currently being used in clinical trials with
promising results. Bone marrow transplantation has proven to be
a cure in a very limited number of cases, yet only a few people
are eligible for this extremely risky procedure (which, if successful,
requires a lifetime of post-surgical maintenance with anti-rejection
drugs). Many people are also exploring alternative types of treatments
such as bio-feedback, acupuncture, herbal medicine, and meditation.
How Do You Know If You Have Sickle Cell Trait?
How Do You Know If You Have Sickle Cell Trait?
The easiest way to find out if you have the trait is to be tested
by a simple blood test. This test is available in several hospitals,
clinics, and in some university health centers. If you and your
partner test positive for hemoglobin S or another abnormal form
of hemoglobin, and you wish to become pregnant, it is imperative
that you have genetic counseling to determine your risks for having
a child with sickle cell disease.
Tips For People In High Risk Groups
For those population groups known to be susceptible to sickle cell
disease, it is recommended that they read or strive to know more
about the disease manifestation. Genetic counseling and screening
for preventive measures is highly recommended. Also, information
on genetic transmission of the disease is highly advisable before
making reproductive decisions. For those who have been identified
as having sickle cell disease, they should be aware of situations
that can lead to crisis. These situations include bacterial infections,
stressful environments at home and in the workplace, dehydration,
sudden temperature variations, and overexertion. |
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Adapted
from material produced by the NIH, 1996.
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