Breaking down the science of PNH

What causes PNH?

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare blood disease that occurs as a result of a genetic change (mutation) during the creation of red blood cells. This mutation leads to a production of abnormal red blood cells, also known as PNH red blood cells, that break more easily compared to normal ones.

Why are PNH red blood cells different?

Normal Red Blood Cell

Normal red blood cell

Normal red blood cells have protective proteins that act as a natural shield against the body's complement system, which supports the immune system by fighting infections.

What is hemoglobin?

Hemoglobin is an important protein that carries oxygen around the body. In PNH, a large amount of hemoglobin is released and eliminated in the urine after hemolysis. This leads to low hemoglobin, and as a result, low oxygen, which can cause an array of symptoms seen in PNH.

What is the role of the complement system in PNH?

The complement system consists of a group of proteins in the blood. They form a pathway that, when activated, helps support (complement) the immune system by fighting infections.

The complement pathway turns on when C3 is activated

complement pathway activation diagram

What are the signs and symptoms of PNH?

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Both IVH and EVH can be responsible for ongoing symptoms in PNH.

Talk to your doctor

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