Hemolysis Is the Cause of PNH
What you should know about hemolysishemolysisThe destruction of red blood cells by complement, a part of the body’s natural defense system. Hemolysis is the main cause of the signs, symptoms, and serious health problems in PNH, including some that are life-threatening.
- Hemolysis is the destruction of red blood cellsA type of cell found in your blood that delivers oxygen and removes waste (carbon dioxide) in your body. Red blood cells affected by PNH are attacked and destroyed because they are missing a protective protein. by complementAlso known as Complement Cascade; in healthy individuals, a sequence of protein reactions in the blood that is part of the body’s natural defense system. It helps fight against bacteria and other foreign matter in the body., part of the body's own defense system1
- In PNHA disease where red blood cells are created without a protective protein. This causes them to burst (a process called hemolysis) and can result in serious health problems. Signs and symptoms include stomach pain, difficulty swallowing, anemia, shortness of breath, and fatigue. Life-threatening complications from PNH include blood clots, kidney failure, and damage to organs., hemolysis is always happening2,3
- Ongoing hemolysis is the root cause of the signs, symptoms, and serious health problems of PNH2,4
- A simple blood testA test done to look at parts of the blood. Examples of tests include complete blood count (CBC), LDH, and high-sensitivity flow cytometry. Results from these blood tests provide information about your PNH. for LDHAn enzyme found in red blood cells, released during hemolysis. Testing for LDH can help show how much hemolysis is happening in your body. measures the level of your hemolysis5
- Reducing hemolysis is key to managing PNH6
PNH is just like an iceberg
What you can't see or feel can hurt you the most2,4
You cannot always see or feel hemolysis, which makes it tough to discover. Left unmanaged, hemolysis can make you feel very tired and weak. It can also lead to signs and symptoms like2,4:
- FatigueTiredness, trouble concentrating, dizziness, and weakness to the point where even normal, everyday activities become a struggle. In PNH, fatigue is often out of proportion to the amount of anemia, as measured by hemoglobin, because it is affected by hemolysis.
- Impaired quality of life
- Trouble swallowing
- Stomach pain
- Shortness of breath
- Dark-colored urine
- Erectile dysfunction (ED)A condition found in men that affects their ability to achieve an erection.
Why is hemolysis so bad?
When red blood cells burst during hemolysis, they release hemoglobinThe oxygen-carrying, reddish-brown material found inside red blood cells. When it is released into the bloodstream during hemolysis, it becomes free hemoglobin. Free hemoglobin is harmful and can lead to serious health problems.. Hemoglobin is good for the body when it’s inside your red blood cells. When it’s outside, it is very dangerous and can harm your body in many ways.2,7,8
Even if you can't see or feel hemolysis, you can still have serious health problems. These health problems can include:
- Kidney failure9,10
- Blood clotsBlood clots form when parts of your body’s blood clump together. In a healthy body, this can stop bleeding when you’re cut or injured. But in certain conditions, these clumps can block blood flow in the veins and arteries, which can be dangerous. In PNH, a clot can happen at any time and can cause serious health problems.11-13
- StrokeRapid loss of brain function due to a lack of blood supply to the brain, as a result of a blood clot or ruptured artery in the brain. Strokes can be life-threatening.11-13
- Heart attackDamage to an area of the heart muscle that is deprived of oxygen, usually due to a blood clot in the coronary artery. Heart attacks are serious and can be fatal.11-13
- Damage to your liver, brain, and lungs11,12
In this way, PNH is just like an iceberg—what you can't see or feel can hurt you the most.
Is there a test for hemolysis?
Your doctor can test for hemolysis through a simple blood test for lactate dehydrogenase (LDH)An enzyme found in red blood cells, released during hemolysis. Testing for LDH can help show how much hemolysis is happening in your body.. LDH is an enzymeA type of protein that helps reactions/processes happen in the body. found inside red blood cells. If you have high levels of LDH in your bloodstream, it means a lot of your red blood cells have been destroyed.5
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Dr. Jack Goldberg, a specialist of blood and blood diseases, explains how destruction of red blood cells by the body’s immune system can lead to a condition called intravascular hemolysis.
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