Immune Thrombocytopenic Purpura (ITP) is a bleeding disorder caused by an abnormally low level of platelets. Platelets are found in the bloodstream and are needed for blood to clot properly. When blood does not clot properly, there is a tendency to bruise and bleed easily.
ITP is caused by a disturbance in the immune system. Usually, the body will manufacture antibodies that coat disease-causing organisms, aiding their removal by the spleen. This process helps the immune system fight infection in the body. In ITP, the body mistakenly produces antibodies against its own platelets. When these antibodies coat the platelets, they are rapidly and prematurely destroyed by the spleen.
The actual cause of ITP is unknown. It can affect adults or children; it can occur without warning and for no apparent reason, or it can occur as a result of a primary illness or infection. It can be acute, lasting less than six months or it can be chronic, lasting longer than six months. In some cases, ITP resolves itself without treatment; however, in many cases, treatment is required.
There is no evidence to suggest that ITP is inherited or related to personal habits or diet. It cannot be passed to other people like the common cold.
Your physician is familiar with the treatments available and will select the one that is best for you.
Anti-D
WinRho® SDF is an anti-D Immunoglobulin that is specially prepared to have high levels of the specific antibody, anti-D. WinRho® is believed to work by blocking the destruction of platelets in the spleen. WinRho® SDF is effective in increasing platelet counts in chronic and acute paediatrics and in chronic adults who are Rh positive. WinRho® SDF is given intravenously and administered in about 5 minutes. One of the benefits of WinRho® SDF is that it only takes one day to administer.
IVIG
IVIG (intravenous Immune Globulin) is a mixture of antibodies that works by blocking the destruction of platelets in the spleen. A large volume of IVIG is given intravenously and administration can take several hours over a period of 1-5 days.
Oral Steroids
Steroids are common initial therapy; however, the beneficial effects of steroids generally do not last for an extended period of time. Steroids are thought to work by slowing the destruction of platelets in the spleen. Steroids may suppress the immune system, which increases the risk of an infection. Oral steroids are usually taken daily for a period of 21 days.
Splenectomy
A Splenectomy is the surgical removal of the spleen. It is usually recommended only if the other treatments have not successfully raised platelet counts. Although removing the spleen may treat the disease in some patients, there is an increased risk of infections.
WinRho® SDF contains a concentration of antibodies that specifically bind to Rh positive red blood cells. "Rh" refers to a particular protein on the outside of the red blood cell. If your red blood cells have this protein, your blood type is "Rh positive"; if they don't, your blood type is "Rh negative". About 85% of the population is Rh positive.
When administered to an Rh positive patient, it is thought that WinRho® SDF coats the Rh positive red cells, causing their destruction by the spleen, thereby decreasing the destruction of platelets. This results in increased levels of circulating platelets and an alleviation of the symptoms of ITP.
In clinical trials, WinRho® SDF has been demonstrated to be highly effective, with a response rate of greater than 75% in all patient categories for which it is indicated.
Mother and her baby, an important blood group
difference
Pregnant women often have different blood
groups from their babies. This is normal and usually not
a problem. However, in some cases, these blood groups differ
in an important way, which is the presence or absence of
a particular protein on the outside of the red blood cell.
If you have this protein, you are "Rh positive".
If you do not have this protein, you are "Rh negative".
Sometimes during pregnancy and delivery,
a small amount of the baby's blood can cross the placenta
and enter the mother's blood stream. This can also happen
in events such as a miscarriage, abortion and amniocentesis.
If this transfer of blood occurs from an Rh positive fetus
to an Rh negative mother, the mother's immune system will
see the baby's blood as "foreign" and will produce
antibodies that destroy the baby's blood cells.
In the first pregnancy, most of these antibodies will remain
in the mother's circulation and the baby is usually not
significantly affected. During subsequent pregnancies, however,
a problem may occur if the new baby is Rh positive and if
there is another transfer of blood across the placenta.
The mother's immune system has a good memory. It can rapidly
produce the same antibodies again, and they can re-cross
the placenta in large numbers and start to destroy the new
baby's own blood before birth, causing a number of serious
complications.
Babies who have this condition are said to have Hemolytic
Disease of the Newborn (HDN).
 |
| A. |
Rh-negative woman with Rh-positive fetus |
| B. |
Cells from Rh-positive fetus enter mother's
bloodstream. Woman becomes sensitized- antibodies
(λ)
form to fight Rh-positive blood cells. |
| C. |
Woman's body retains a memory of these antibodies
|
| D. |
In the next Rh-positive pregnancy, the woman
produces large numbers of antibodies which attack
fetal blood cells |
|
 |
- WinRho® SDF is up to 99.9% effective in preventing
HDN when administered correctly.
- WinRho® SDF is an injection of antibodies administered
with every pregnancy, when the mother is known to be Rh-negative.
It works in the bloodstream to destroy any circulating
blood cells from the baby before the mother's immune system
has a chance to make its own antibodies. The baby is not
affected by this injection.
- Injections may also be given in connection with abortion,
miscarriage or amniocentesis.
- As a result of the WinRho® SDF injection, the mother's
immune system never makes its own antibodies to the baby's
Rh positive red blood cells, so mother and the baby are
protected from HDN.
Reactions to WinRho® SDF are rare in Rh-negative individuals.
Discomfort and light swelling at the site of injection and
slight elevation in temperature have been reported in a
small number of cases.
WinRho® SDF can be administered in about five
minutes through a single injection into a suitable vein.
Depending on response the patient may require subsequent
injections at intervals to be determined by the attending
doctor.
Many WinRho® SDF patients never experience any drug-related
adverse effects. Among the few patients who do, the most
commonly reported effects include headache, chills and fever.
Other reactions include back pain, shaking, chills and pink
urine.
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