Q&A with Dr. Richard Ward – Thalassemia and Infections
September 6, 2018 – Below, Dr. Richard Ward answers some commonly-asked questions regarding infections and thalassemia.
Infections can be caused by many different types of “bugs” or organisms. The most common are bacteria (e.g. pneumonia) and viruses (e.g. flu). The immune system helps you to fight infections. It is made up of white blood cells and proteins. Neutrophils are white blood cells that fight bacteria. T-Lymphocytes are cells that are important in fighting viruses. B-Lymphocytes help the body to remember old infections and to destroy them. They do this by making antibodies which are proteins that recognize bits of an infecting organism. These bits which are recognized are called antigens. Antibodies stay in your body so you usually won’t get sick from it a second time. This is also how immunizations work. An immunization contains an antigen that doesn’t cause an infection but does allow the body to produce antibodies. T-lymphocytes destroy infections that have been detected by antibodies. Antibodies can also trigger proteins called complement that are another part of the immune system that helps to kill infections. The spleen is a small organ in the upper left part of the abdomen below the ribcage. It filters blood and makes lymphocytes. The spleen plays a very important role in helping your body fight infections . Some parts of the immune system you are born with and others develop as we go through life and come across infections. These are called innate and adaptive immunity. One of the first signs of an infection is a fever. If your temperature is above 101.5F (38.5C) you should seek medical advice.
People with thalassemia who get transfused worry about getting infections from blood transfusions, but what about infections that aren’t connected to blood transfusions? Are people with thalassemia at greater risk of contracting infections, or are they likely to have a stronger reaction to an infection?
The blood supply in North America is very safe these days with risks of viral infections less than 1 in a million. You should continue to take the Hepatitis B immunization so you stay protected. Other infections can also be caught from blood so blood centers are constantly working to make the supply of blood as safe as possible for infections now and in the future.
If you have excellent control of iron levels in your body and do not have any major complications such as diabetes your risk of infection with thalassemia is probably not increased that much compared to someone who doesn’t have thalassemia. Unfortunately, many people with thalassemia do not have such good iron levels. Infection is sadly one of the main causes of patients passing away from thalassemia.
If a patient has had their spleen removed, does that affect their likelihood of getting an infection or the severity of that infection?
Yes. Your spleen helps to filter your blood and makes lymphocyte white blood cells. If you have had your spleen removed, you are at risk of infections and also of the infection being more severe as your body cannot defend itself as well. There are immunizations that you should receive if you have had your spleen removed. These will protect you against infection from: Pneumococcus, Meningococcus and Hemophilus influenze B. The Centers for Disease Control (CDC) provide advice on how often you should have the immunizations: https://www.cdc.gov/vaccines/schedules/hcp/imz/adult-conditions.html At this time, the advice is to receive the Meningitis vaccine every 5 years, the HiB once in adulthood and to have had the Pneumococcal series of vaccines. There is also a fairly new Meningitis vaccine (Bexsero or Trumenba) that is also recommended for teens. The advice is quite complex and changes so it is important to check in with your health care team on a regular basis so that you are up to date. If your child has had their spleen removed they will often be asked to take penicillin every day to reduce the risk of infection. When you travel to a rural area or out of country, you should take with you a course of antibiotics in case you develop a fever and cannot reach medical care quickly. If you have had your spleen removed, there are also other infections to be aware of including Babesiosis. This is spread by ticks (similar to Lyme disease) and is common in the northeast states. Your thalassemia clinic may have a wallet card you can carry to inform others of your spleen status. Another option is a medical alert bracelet.
What about iron overload and iron chelation – how do each of these impact infection in thalassemia?
Research has shown that high amounts of iron overload in your body reduces the levels of some of the proteins of the innate immune system and so increase your risk of infection. As you remove the iron with chelators, these protein levels increase and provide better protection against infection.
Any iron chelation medication you take can possibly increase how bad some infections may be. Many infections are siderophores. This means that they feed off iron and so grow quicker when there is lots of iron around. Usually iron is stored in the liver and not easy for infections to get to and eat. When you take your chelator you move the iron from the liver into the blood as it passes out of the body. This means the iron is easier for the infection to get hold of.
If you take Deferiprone (Ferriprox) there is a higher risk of infection. This is because the medication can reduce the number of neutrophil white blood cells you have in your body to very low levels (neutropenia). This means you are less able to fight bacterial infections. This is the reason why you are asked to have a weekly CBC check whilst taking the medication. The risk of this effect on the neutrophils is highest in the first six months of treatment and uncommon after a year, but can still happen at anytime you are taking it.
If you receive Deferoxamine (Desferal) through an IV line, this is also a possible way for infections to enter your body.
What about some “common” infections, like a urinary tract infection? Is that more likely to occur in thalassemia, or is it more dangerous if it does occur? Does it need to be treated differently? If so, what kind of information should a person with thalassemia tell their doctor if he is treating a common infection?
In general, your thalassemia and its treatment does put you at higher risk than others for infections and more severe infections. We do not want you to be prescribed antibiotics when they are clearly not needed (such as a cold or flu) as this can cause resistance and loss of the medication’s effect in treating bacterial infections. But, we do tend to be more cautious with patients where there is some uncertainty. If you see your primary care provider and they are unsure whether to prescribe antibiotics for an infection, it may be safer to ask for assessment and treatment. This may include a throat swab, urine sample or chest x-ray, depending on what’s wrong.
Sometimes infection can develop into sepsis. What does a person with thalassemia need to know about sepsis in order to make sure it is diagnosed and treated properly?
Sepsis is the medical term for when an infection becomes severe and life-threatening. It happens when the immune system that usually fights infection goes into overdrive and produces more and different proteins that then damage your body. The damage, or inflammation, can case organ failure and then death under extreme circumstances. Most health care providers and ERs are experienced in recognizing and treating sepsis. Things to watch out for and concern you with a fever would be not passing as much urine as normal, breathing difficulties or breathing very fast, fainting or light-headedness, your heart beating very fast, or feeling confused. You will probably be triaged very quickly in the ER and receive IV fluids and antibiotics immediately and may be taken to the ICU to be cared for. If you have a high fever and feel very unwell you must seek urgent medical attention and inform the health care team that you have thalassemia and are at increased risk of severe infections.
What steps can a person with thalassemia take to help reduce the risk of infection?
Avoid eating raw foods such as meat, shellfish, cheeses and unpasteurized milk. These foods are more likely to contain infections.
If you take Deferiprone as your iron chelator medication you must stop the drug immediately if you have a fever >101.5F, seek urgent medical attention and have a CBC drawn to make sure you do not have a low neutrophil count (neutropenia). It is advised to stop all chelator medications if you have a significant infection, though not for a simple cough or cold. If you are prescribed antibiotics, check with your hematologist. They may advise you to not take your chelator until you have finished the course of treatment.
If you have a port-a-cath or PICC line for venous access, these are also ways for infections to enter your body. You must ensure you know how to care for the line and what to look out for, such as redness or pain in the area. If you become sick, make sure to ask the healthcare provider to take blood cultures and give you antibiotics that will help specifically treat line infections.
If you have had your spleen removed you need to seek urgent medical assessment if you have a fever higher than 101.5F/38.5C and ask for antibiotics to be given.
What else should a person with thalassemia know about infections?
There are some other aspects of living with thalassemia that can affect your chances of having an infection. If you have high iron levels for a long time, you may have become diabetic as a result. Diabetes is known to increase your risk of infection. This is similar to how iron can increase the risk. The infections can eat the high amounts of sugar in your body if your diabetes is not well controlled. If you have hormonal problems from iron overload you may be lacking in estrogen. This can change the lining of the vaginal and cervix and increase the risk of infections in that area of your body. Kidney stones are more common in people with thalassemia. You are at higher risk of kidney infections if you have a kidney stone.
There are many great resources on the internet that provide more information on infection: the CAF website, TIF publication on emergency management of thalassemia, and CDC.gov to name a few.