TORONTO -- Four-month old Boston De Castro has had to endure seven rounds of chemotherapy while his family waits for a stem cell donor match to save his life. A little over a month ago, Boston was diagnosed with a rare and life-threatening disease, hemophagocytic lymphohistiocytosis (HLH), a severe systemic inflammatory syndrome.

But Boston, who is half-Filipino and half-Caucasian, needs a donor with a similar ethnicity, which is very difficult to find.

“He’s doing really well considering the circumstances for sure” mother Simone Jannetta told CTV’s Your Morning from their home in Winnipeg on Thursday.

“We haven’t had any good news yet for a new match, but our doctor’s checking every two weeks for us on the registry. So we’re hoping to hear some good news soon. But we still have high hopes, as it does take a few weeks for people to get their kits and send it back to them on the registry.”

Boston appeared to be a healthy baby at first, but a fever when he was less than three months old prompted his parents to take him to the hospital emergency department as a precaution.

“When we got there, they found out all his blood levels were low, his liver and spleen got really big, and he turned yellow. He just started to deteriorate really quickly in the hospital, but leading up to it, it was just a fever,” Jannetta said.

The family is happy to finally be home again after spending a month at the hospital.

“We’re just grateful for everything during the day, and all being home together, it’s just such a blessing,” Jannetta said.

Still, without the security of a hospital environment, any little change they see in Boston can be a little scary for Jannetta and father Rex De Castro.

“We have to give him all the medication. There’s obviously the fear factor of not having medical people around,” De Castro said with emotion.

“Not having people around when he feels a little warm, or if he’s a little bit off. We just feel a little bit helpless at home,” Jannetta added. “But other than that, it’s great. We’re just happy to be at home.”

This is not the first time the De Castro family has had to deal with health issues with their children. According to their Go Fund Me page, their two-year-old daughter Beatrix was diagnosed with neutropenia, a rare disease involving an unusually low number of a type of white blood cell.

HOW TO BE A STEM CELL DONOR

Fewer than 25 per cent of those who need a stem cell transplant find a match within their own family, according to Canadian Blood Services. The odds are more likely of finding a match with someone who shares the same ethnic background, the organization adds. Two-thirds of stem cell registrants are Caucasian, while a dozen different ethnicities -- including Black-African (0.4 per cent) -- make up a mere 4.3 per cent of the registrants. Only 3.5 per cent of potential stem cell donors are of mixed ethnic background, making Boston’s chances of finding a match challenging. The diversity for cord blood donation is significantly higher, with Caucasians accounting for about 38 per cent, according to agency data.

Prime Minister Justin Trudeau also called on Canadians to donate, tweeting earlier in November: “Can you save Boston’s life? There are two ways you can help: If you’re half Caucasian and half-Filipino, please reach out to @CanadasLifeline and see how you can become a stem cell donor. If you aren’t, you can still share this story and spread the word.”

It is a “long-term commitment” to be on the stem cell registry, Canadian Blood Services says, and more complicated than making a blood donation.

“It may take weeks, months or even years before you get the call to donate stem cells,” the organization, which seeks donors between the ages of 17 and 35, said on its website. But the group recently said only 50 per cent of potential donors who are registered actually follow through with the procedure when the call finally comes, making commitment especially important.

The COVID-19 pandemic has further complicated the situation, according to Canadian Blood Services. Most Canadian patients in need of stem cells depend on international stem cell donors, but with borders closed and travel restrictions in place, patients and transplant centres must rely more on Canadian donors, a spokesperson said. Recruitment of new donors has also become more difficult, now that in-person recruitment swabbing events are also suspended.

When you donate, the process requires a comprehensive health screening to determine eligibility, including a physical examination and routine medical tests by a doctor at the hospital where the donation would occur. Potential donors would need to be free of infectious diseases to ensure there are no risks to the donor or the recipient.

There are two types of stem cell donations a donor may be asked to make: either peripheral blood stems cells (PBSC) or bone marrow.

The first is collected from circulating blood after a donor has taken a cell growth stimulating drug to increase the volume of stem cells in the blood. The collection method, called apheresis, is regularly used for plasma and platelet donations. It separates and collects the stem cells during the donation, with the remaining blood components going back to the donor. It is a non-surgical procedure that takes about four to six hours, with a potential second donation the following day. There are mild, short-term side effects that typically disappear within a couple of days of the procedure.

The bone marrow donation, which is the one Boston needs, requires surgery under anesthesia. The 45 to 90-minute procedure involves withdrawing liquid marrow from the back of the pelvic bones. While overnight hospital stays are typically not required, some time off work will be needed. There are some risks associated with anesthesia, as well as other very rare, but potential risks, such as infection at the surgical site, nerve, bone or other tissue damage that may require additional treatment. Other side effects like fatigue and other discomforts may last a few days to several weeks.

There is also another type of donation expectant parents can also consider: donating their baby’s cord blood to the agency’s cord blood bank.

Meanwhile, the De Castro family is hopeful that Boston, who still has roughly three weeks of chemotherapy left, will find a donor over the next two to four weeks.

“We focus every day on just trying to make the best family day we can, because nothing’s promised, right? So until that time comes, we’re literally just trying to make every day the best for our children,” De Castro said.

To see if you could be a match for Boston, click on http://www.blood.ca/Match4Boston in Canada, or at https://bethematch.org/ for U.S. or international donors.