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Understanding PNH

What is PNH?

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare and complex blood disease that involves the destruction of red blood cells and can present as anemia, blood clots, and/or bone marrow failure. PNH can lead to life-threatening complications.

How rare is PNH?

Each year, roughly 500 people in the US are diagnosed with PNH.
An estimated ~10-20 million individuals around the world have PNH.
On average, people are diagnosed with PNH when they’re in their 30s and 40s.

What causes PNH?

In people with PNH, certain red blood cells are destroyed by a part of the immune system called the complement system. This destruction of red blood cells is called hemolysis.

With PNH, some of your red blood cells are missing certain proteins that protect them. Without this protection, they are attacked and destroyed by a part of the immune system called the complement system.

There are 2 types of hemolysis that occur when you have PNH

Intravascular hemolysis (IVH): Your red blood cells are destroyed within the blood vessels (like veins and arteries).
Extravascular hemolysis (EVH): Your red blood cells are destroyed outside the blood vessels, within the liver and spleen.
PNH patient disease awareness uncovering hemolysis resource
Learn more about hemolysis in PNH
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IVH and EVH—two key drivers of PNH—both should be addressed

Hemolysis lowers your hemoglobin level

Hemoglobin (Hb) is the protein in your red blood cells that carries oxygen throughout your body. In PNH, as red blood cells are destroyed, hemoglobin levels go down.

A hemoglobin level of at least 12 or 13 g/dL is considered normal. Hemoglobin levels that are steady but below 12 or 13 g/dL could mean your hemolysis in PNH is not well controlled.
Normal adult hemoglobin levels vary, but generally are 12-16 g/dL for women and 13-18 g/dL for men.
“My hemoglobin levels give me insight into how I’m feeling.” Brandi, a real patient with PNH, compensated for her time.

Hemoglobin levels below normal can result in PNH symptoms, like fatigue and shortness of breath

PNH is different for everyone

One person may have mild symptoms, while another could have severe symptoms and require blood transfusions.
 

Common signs and symptoms of PNH are:

Fatigue or weakness
Shortness of breath
Brain fog
Headaches
Anemia
Bruising/bleeding easily
Dark-colored urine
Abdominal pain

Any symptoms, mild or severe, may be a sign that your PNH isn’t fully controlled. It’s important to let your doctor know how you’re feeling

“Some days were worse than others. Sometimes I felt too tired to work or socialize and would have to go home early.” Alvaro, a real patient with PNH, compensated for his time.
“My thinking was really slowed down. Everything felt heavy.” Zack, a real patient with PNH, compensated for his time.
Learn about some of the challenges patients with PNH may face
Find out more

PNH, paroxysmal nocturnal hemoglobinuria.