A person may need donated blood for several reasons. The most well-known of these is blood loss due to an accident or surgery but there are also other conditions such as treatment for cancer which could leave someone’s blood depleted.

Donated blood is separated into its components, red cells, white cells, platelets and plasma and these are used directly to treat patients and can also be made into vaccines and other medical products.

Pathology testing is used to determine a person’s blood type and donated blood is screened for a number of diseases, these are:

• HIV 1 & 2
• Hepatitis B and C
• Syphilis
• Human T-cell lymphotropic virus (HTLV)
• Cytomegalovirus (CMV)
• Some blood is also tested for malaria

As well as testing for antibodies, which is the standard type of testing for these viruses, in the cases of HIV-1 and hepatitis B and C, the Blood Service also uses Nucleic Acid Testing (NAT). This type of testing looks for the presence of the actual virus via its DNA (or RNA).

A test which looks for antibodies is based on the body’s response to the virus, but during the earliest stages of infection a person’s body may take time to respond and produce antibodies. This means that NAT testing adds an extra layer of protection and further reduces the risk of infected blood entering the blood supply.

So what happens when the blood gets to hospital?

Pathology is at the interface between the Blood Service and the patient. Pathology laboratories that service trauma centres or hospital wards likely to need to transfuse patients (i.e. maternity, surgical, oncology wards) will order units of blood from the Blood Service that they keep to hand in large fridges.

When a doctor requests a transfusion, they will send a tube of blood from the patient urgently to the laboratory. The pathology staff will then check the compatibility of the patient blood with donated units – a process called cross-matching.

Cross-matching involves mixing a small sample of the patient’s blood together with a small sample taken from the donated blood unit and watching what happens. If the mixed blood clumps together, it cannot be transfused. If it mixes together without any clumping, it is can be used.

So what causes this clumping? Many people are familiar with the terminology of ABO blood typing, and Rhesus blood typing. For example, O+ or B-. These refer to antigens and antibodies in the bloodstream. The ABO and Rhesus antibodies are the most significant systems of antibodies in our blood. But beyond these are a vast array of antibodies that are less-well known, but can cause complications if the wrong blood is transfused.

Every single unit that is transfused in Australia is carefully assessed by pathology staff to make sure that none of these antibodies react with the patient’s blood. Any laboratory that provides transfusion services is subject to incredibly strict quality control checks and all staff must be fully trained.

As well as the rigour of testing and cross matching, Australia’s blood supply is also amongst the safest in the world because of the restrictions placed on who can donate.

Most people aged between 16 and 70 are eligible to give blood, however people who lived in the UK for more than 6 months between 1980 and 1996 cannot donate. The reason for this is human variant Creutzfeldt-Jakob disease (vCJD). This is the human form of ‘mad cow disease’ and there is currently no way to screen blood for it, which is why people who may be at risk of carrying the disease are excluded from giving blood.

Although blood transfusions are still considered safe and in many cases are necessary to save a person’s life, concerns have been raised more recently that doctors must be cautious in how they approach transfusions, as they still have some risks for patients.

Pathology testing is vital in helping doctors to determine a person’s transfusion needs (such as looking at haemoglobin levels) as well as identifying preventative measures; for example treating underlying anaemia prior to surgery, which could mean a patient does not need donated blood.

^{Image credit: Royal College of Pathologists of Australasia}

The post How pathology keeps our blood supply pumping first appeared on Know Pathology Know Healthcare.

The ABMDR helps people who need bone marrow and stem cell transplants because of blood cancers, genetic disorders and immune conditions.

Pathology plays a vital role in bone marrow donation. Becoming a registered donor involves giving a blood sample at an Australian Red Cross Blood Service centre. Pathology teams test donors’ blood to find out their human leukocyte antigen (HLA) tissue type and this information is stored by the ABMDR.

HLA are proteins that your immune system uses to recognise which cells belong in the body and which do not, so a donor must be carefully selected to minimise risk to the patient. HLA typing is more complex than blood typing, making matching donors to patients more difficult.

Only around 30% of patients will match with a family member and as 34 people a day are diagnosed with a blood cancer, the ABMDR needs as many donors as possible.

Unfortunately finding a match can also be affected by ethnicity – a person is more likely to find a match with someone who shares their ethnic background. As 80% of people registered as donors are of ‘Northern Caucasian’ backgrounds, people of other ethnicities may be left with little hope of finding a lifesaving match.

Ur the Cure is an organisation set up to promote the ABMDR and particularly to raise awareness of the need for donors from a range of ethnic backgrounds, to help people like Melissa Baker who has Italian heritage.

Melissa is a Victoria-based Forensic Pathologist who understands the value of pathology for both professional and personal reasons – she has a stubborn form of Hodgkin’s Lymphoma.

In June 2013, Melissa noticed some small lumps in her neck. With her medical background she suspected lymphoma, which was verified by pathology tests. According to Lymphoma Australia, Melissa is one of the 5,000 cases of lymphoma that are diagnosed in Australia each year.

“Believe it or not, I’ve been told that I’m ‘lucky’ because Hodgkin’s Lymphoma is a ‘good’ cancer to get as there is a high chance of remission and cure. That’s not helpful, especially in light of the fact that I underwent 15 gruelling months of chemotherapy including an autologous stem cell transplant, which is a transplant using my own stem cells, but my cancer did not respond as hoped. I then tried a new drug which unfortunately wasn’t subsidised by the government’s Pharmaceutical Benefits Scheme.”

The new drug cost Melissa, a single mum of two young children, $10,600 per treatment. With the support of her family, friends and Lymphoma Australia, Melissa raised money to help her, and hopefully others in a similar position, pay for the expensive treatments.

“After an initial good response, unfortunately my lymphoma began to progress again after nine treatments.  I am now waiting for a clinical trial to open so I can access a new type of drug that will use my own immune system to fight the cancer.  The hope is that I will have a good response and consolidate that with another stem cell transplant, this time using donor stem cells. My last hope for a cure is finding a compatible donor, but so far a world-wide search for a donor has not been successful. It is easy to join the bone marrow and stem cell registry – you can be added when you donate blood with the Australian Red Cross Blood Service. I plead with anyone donating blood to join the registry to help me and others like me.”

Despite the difficulties Melissa has faced, she is adamant about the value of pathology in getting her this far and has hope for the future with the drug and donor stem cell transplant.

“The diagnosis via biopsy gave my doctors and I the information we needed to plan my treatments. Throughout it all, I have had regular pathology tests to monitor my ongoing health.”

The Ur the Cure campaign is using social media to spread the word and get more potential donors, you can like and share the Facebook page to help get the message out.

Founder of Ur the Cure, Pamela Bou Sejean is keen to dispel common misconceptions about donating stem cells; “Donating stem cells is easier these days, it’s much like a blood donation where your stem cells can be taken straight from the bloodstream. The non-surgical procedure can take about 4 hours and you can watch TV or read a book during it and return to normal activities afterwards. Pretty simple considering you could save a life!”

Pamela points out that only 1 in 1500 Australians in any given year is a match and will be asked to donate stem cells.

To learn more about becoming a bone marrow donor, visit http://www.abmdr.org.au/

To join the ABMDR call the Red Cross Blood Service on 13 14 95 and book an appointment – you will need to specifically mention the ABMDR.

To support Melissa through her fundraising with Lymphoma Australia, visit http://www.everydayhero.com.au/event/igotthegoodcancer

The post Get on this list to be a lifesaver first appeared on Know Pathology Know Healthcare.