F.A.Q.

Taking paracetamol, birth control pills or ADD/ADHD medication is generally not a problem, which means you can still register as a stem cell donor. Take a look at the page 'Who can become a stem cell donor' for more information about the conditions/types of medication that will (not) prevent you from becoming a stem cell donor. 

Matchis will send the cotton swabs containing your cheek mucosa samples to a laboratory, which will use them to isolate your DNA. The lab does not receive any personal data concerning you, only a barcode that can only be traced back to you through Matchis. 

The DNA forms the basis for determining your tissue profile (HLA), which is used to match you to a patient. To update your tissue profile with new characteristics when technological developments allow, the lab will store your DNA indefinitely. This means an even more accurate match can be made over time. Matchis will never share your personal data with the lab without your explicit written consent. 

Yes, absolutely! It is certainly possible to be both a blood donor and a stem cell donor. If you get called up by Matchis as a potential match and you are reserved for a specific patient, we ask that you do not donate any blood during this period. This ensures that your body is optimally prepared for a stem cell donation.  

We also recommend not donating any blood for a period of six months after donating your stem cells to allow your blood values to return to normal.  

Currently, you can only register as a stem cell donor during one of the donor drives organized by Matchis Caribbean. If you are unable to come to a donor drive, you can keep an eye on our website for news about upcoming donor drives. In the future, we will be exploring the possibility of setting up more structural registration locations. 

No, that is not possible at this time. If everything goes as planned, we will begin expanding our activities to other Caribbean islands in 2027.  

In that case, we advise you to register with the Matchis Foundation in the Netherlands. You can do so by completing the online registration form at www.matchis.nl. The cotton swabs you need will be sent to your address in the Netherlands. 
If you happen to be on Aruba when there is a donor drive, you can also register as a stem cell donor there. 

If you decide to deregister as a stem cell donor, Matchis Caribbean will delete your personal data from its registry. Of your birth date, only your birth year is stored. Your name, address and hometown are also deleted. This means any personal data that were shared with other organizations (e.g. the laboratory that determined your tissue profile or foreign transplantation centers) can never be traced back to you as an individual. After all, these organizations only had access to the unique number (i.e. pseudonymized data) that only Matchis could link to your personal data. After you deregister, that is no longer possible. 

We do not accept any elevated risk whatsoever for our voluntary donors, as the medical procedures they undergo offer no health benefits for them. We are very strict about this and a donor physician's decision is final. 

A donation with an elevated risk is not allowed under any circumstance, not even on the condition that the donor personally accepts this risk. In addition to the safety of our donors, we must also protect the safety of patients, who are negatively impacted if a donation is canceled or terminated at the last minute due to complications with the donor. 

Furthermore, it is our duty to ensure that stem cell donation continues to be known as a safe procedure in order to maintain the system of voluntary donations. 

You can still register as a stem cell donor if you are pregnant. Your pregnancy does not affect the collection of cheek mucosa samples with the cotton swabs. However, you are only allowed to actually donate stem cells from six months after your pregnancy and provided that you are not currently breastfeeding (or are willing to stop breastfeeding for a week). 

We therefore ask that you inform us about your due date via the contact form. Once your registration is complete, we will temporarily set your donor status to ‘non-active’ in your system. 

Just because your HLA typing has been determined for a sibling or other family member does not automatically make you a stem cell donor with Matchis Caribbean. For that to happen, you must register as a stem cell donor and collect cheek mucosa samples using our registration kit.  

The reason why we want to repeat the HLA typing is because a hospital performs a less comprehensive typing procedure. A detailed typing is only performed once you are actually found to be a match with a family member. 

That is why we want to send new cheek mucosa samples to our lab, so a detailed typing can be performed and the chance of finding a match increases. 

There are two ways to donate stem cells: via your blood or via your bone marrow. You can learn more on the page 'How stem cell donation works'.

Stem cell donation via the blood

Side effects of G-CSF 
Administering the growth factor G-CSF may cause mild to moderate bone and muscle pain as a side effect, which is easily treated with paracetamol. Some people experience flu-like symptoms like fatigue, mild fever and/or headache. Some donors report that they have trouble sleeping or experience a slightly elevated body temperature while using G-CSF. Side effects such as nausea, night sweats and dizziness occur rarely. Occasionally, the injection site may become irritated. These symptoms generally pass within one or two days. 

One of the side effects of G-CSF is that it may exacerbate the symptoms of autoimmune diseases, asthma and allergies.

The long-term effects of G-CSF 
Currently, no long-term adverse effects of G-CSF are known. Studies have focused primarily on a potentially elevated risk of conditions such as cancer. This substance has been used for this application in healthy donors since the early 1990s.

Side effects of extracting stem cells from the blood 
The process of donating stem cells via the blood may take up to six hours. For a number of hours, part of your blood continuously flows through the machine. As your blood cools down outside your body, you may feel cold during the procedure. In that case, a blanket can help. 
 
Along with your stem cells, the machine may also collect some blood platelets. This means the number of blood platelets in your body may decrease. Your blood platelet count is therefore checked both before and after the donation procedure. Generally, the number of blood platelets does not become low enough to be a problem.

Stem cell donation via the bone marrow

Pain? 
Donating stem cells from the bone marrow is painless, as this procedure is always performed under general anesthesia. For this method of donating stem cells, the standard risks of anesthesia pose the largest risk. After recovering from the anesthesia, you may still feel a bit drowsy. The ventilation tube that is used during the procedure may also cause a rough feeling or soreness in your throat. This will usually pass within a few days. 
 
You may also experience headache and/or nausea. These symptoms will generally pass by the following day. 
 
Extraction 
The stem cells are extracted from the rear edge of the pelvis using a thick needle. For the first few days, you may experience a sore, painful feeling at the puncture site. This is easily treatable with paracetamol. The pain will recede after a few days, although it may take up to several weeks for the feeling to go away entirely. 
 
Anemia 
As the bone marrow in the pelvis is highly vascularized, a relatively large volume of blood (circa one liter) is also extracted along with the bone marrow. This can cause mild anemia, which can make you feel fatigued. Your body will quickly produce new bone marrow and blood to replace what was taken and the anemia will pass after several weeks. If necessary, iron tablets can help. 

The patient's attending physician chooses the method that is best for their patient. As a donor, you can consent to the chosen method; after all, stem cell donation is always voluntary. If your choice does not match the attending physician's preference, that means you will not be a donor for that specific patient. 
 

Based on the type of patient and their condition, it is determined what donation method is best suited for them. There are differences in the properties of the donated ‘product’ between the two types of donation (via the bone marrow and via the blood). As a result of these different properties, the effect that the stem cell product has in the patient's body differs per donation method.

Differences 

When donating via the blood, the product contains a large number of stem cells, which means it can take effect more quickly and the new stem cells can start producing new blood cells faster. The product also contains many white blood cells, which can have a positive effect on the patient's leukemia. A downside of the presence of these white blood cells is that they can trigger so-called graft-versus-host disease (GvHD). That means that the donor's stem cells may start to attack the patient's body.  
 

When donating via the bone marrow, the product contains fewer stem cells and white blood cells. On the other hand, it does contain other components that make the product more effective against certain conditions. When donating via the bone marrow, GvHD is also less common. In the Netherlands, bone marrow donation is currently used to treat specific conditions (e.g. aplastic anemia). Using a bone marrow product is also strongly preferred when the patient is a child.  
Besides the preference of the patient's attending physician and that of the donor, the donor physician also gets a say in choosing the donation method. If a donor is not eligible for a specific donation method, the alternative donation method may be chosen in consultation, even if this is not the preferred method of the patient’s attending physician.   

No, the chance of a match is very small. That is why we need as many potential donors as possible in the global donor registry.  Some donors are called up after just three months, while others may wait three years, fifteen years or never get called up at all. 

If you are a potential match with a patient, we will contact you. You could be registered as a donor for a long time before we contact you.  If this happens we will always ask if you are still prepared to donate cells.

Only then – after you have received extensive information and have had a full medical examination – will the donation of stem cells take place.

What donor is the best match for a patient is ultimately determined by the patient's attending physician. The key factor in this decision is your tissue or HLA typing (stem cell information). It has to match that of the patient. We will contact you if you are a (potential) match with a patient. You do not have to do anything yourself. If you do not hear from us, that means you are not a match. 

  When someone registers as a stem cell donor, their HLA typing (tissue typing) is determined using cheek mucosa samples collected with cotton swabs. The HLA typing predominantly determines if a donor is a good match for a patient. The patient's body uses the donor's stem cells to build its new immune system. If the patient's body rejects the donor's stem cells as foreign or if the donor's stem cells view the patient's body as foreign, serious or even lethal complications may occur. 

  It is therefore important that the tissue typing of a donor's stem cells matches that of a patient as closely as possible. Finding a donor with the right tissue typing is called ‘matching'. 

  The key factors for making a match are: 

• HLA (Human Leukocyte Antigen) is the most important factor. It must be the same or match as closely as possible. Ideally, we are looking for a 10-out-of-10 match.
• Age is another very important factor. A young donor is preferable because the quality of their stem cells is higher and the transplantation of the cells into the patient's body is more likely to succeed. In addition, the risk of complications for the donor increases as they get older.
• Gender is another factor we take into account. Male donors are generally preferable, as their bodies have more stem cells. Some female donors may have been pregnant at some point. This makes their stem cells less suitable for donation, as it increases the risk of rejection symptoms for the patient.
• CMV, also known as the cytomegalovirus, is a generally harmless virus and many people have undergone a CMV infection without even realizing it. However, this virus can cause problems for a patient receiving a stem cell transplantation. That is why we want to know if a donor is CMV positive or negative (i.e. if they have been infected with the CMV virus or not). If a CMV-positive patient receives stem cells from a CMV-negative donor, this can cause serious problems for the patient. To a lesser extent, the same principle applies if a CMV-negative patient receives stem cells from a CMV-positive donor.
• Urgency for the patient, i.e. how urgently a patient needs the stem cell transplantation, is another important factor in the choices we make. We may e.g. choose a donor from a nearby country or opt for an alternative such as umbilical blood, because this is faster.
• Lastly, we consider such factors as the donor's weight, high-risk behavior, travel history in recent months and their availability. 

When you donate stem cells via your blood or bone marrow, you will spend a day in the hospital.  

As the stem cell donation procedure is performed in the Netherlands, you will travel to the Netherlands a few days before the scheduled date of the procedure. When you donate stem cells via your blood, you will arrive circa six days before the donation date. You can return home five to seven days after your procedure. In total, you will spend circa two weeks in the Netherlands.  

When donating stem cells via your bone marrow, you will travel to the Netherlands one or two days before the scheduled date of the procedure and can return home circa seven days after your procedure.  

Our policy is that a donor can be called up to donate their stem cells a maximum of three times. Medically speaking, it is possible to donate more than three times; in that sense, stem cell donation is more akin to blood donation than organ donation. The body quickly produces new stem cells to replace what was lost. 

If you are a match with another patient, we maintain a waiting period of at least one year. If it concerns the same patient as before, you must be fully recovered from your last donation and there is a minimum waiting period of six weeks. It goes without saying that every donation is entirely voluntary. 

Once you have donated stem cells three times, you will still be available to family members who need a stem cell donor. There is no limit to the number of times you can donate your stem cells to family members. It does not affect the number of times you have donated to an unrelated patient. 

Before donating your stem cells, we will conduct an informative interview and you will undergo a medical examination to determine if it is safe for you to donate your stem cells. The medical examination is partially conducted online by a physician in the Netherlands and partially at the hospital on Aruba. In some cases, it may be necessary to conduct the entire medical examination in the Netherlands. During the first phase of the project, the stem cell donation procedure itself will be performed in a hospital in the Netherlands. In the future, we will explore the possibility of performing stem cell donation procedures for donors from Matchis Caribbean in other countries as well. 

All expenses you as a donor incur in relation to the donation process, plus the costs for one family member or friend to assist you, are reimbursed. These include e.g. travel costs, accommodation costs and absence from work. Exactly what expenses are reimbursed is determined ahead of time in consultation with you. You are not paid for the donation itself. 

That differs per person and also depends on the donation method used and the type of work the donor does. Some donors make a full recovery within a few days after the donation procedure. If you have a physically demanding job, it may take longer before you are ready to go back to work. After the donation procedure, donors stay in the Netherlands for another five to seven days before flying back to Aruba.

At the moment, the information and (medical) support provided during the donation process are available in Dutch and English. For that reason, the registration form is only available in these two languages. It is important for us to be able to determine at the time of registration whether a donor has sufficient command of Dutch or English.

We are exploring the possibility of also making the donation procedure available in Spanish and/or Papiamento in the future. This is not yet possible at the moment, however.

You can have your personal data amended by sending us a message via the contact form.  
 
You can request your HLA typing via this form. Send the completed form and a copy of a valid ID (remember to cover up your social security number or make a copy using the KopieID app) to Contact@matchiscaribbean.com. We will send you the requested information securely via Zorgmail.  

You can deregister as a stem cell donor via our contact form. If possible, you can also list your reason for doing so. You will receive a confirmation of your deregistration from our staff. 

If you are moving abroad for an extended period of time or indefinitely, please let us know via the contact form. We will deregister you as a donor, after which you can reregister in your new country. 

If you are not healthy or have a condition that precludes you from being a stem cell donor, please let us know. We will either deregister you or temporarily set your donor status to non-active. Send us a message via our contact form.  

Please include the (medical) reason in your message. 

A person's heritage is an important factor when trying to find a match. A patient has the best chance of a suitable match if the donor has a similar background. That is why it is important that the stem cell donor database accurately reflects the diversity in society. At the moment, that is not yet sufficiently the case. The more people from the Caribbean register as stem cell donors, the better the chance of finding a suitable match for patients from the Caribbean. 

Arubans have access to this care via the National Health Insurance of Aruba.