Understanding PNH

PNH develops when there is a change in a part of the body’s DNA, which is called a genetic mutation. The name of the gene that changes is the PIG-A gene.
Because of this mutation, red blood cells are missing critical proteinsproteinsLarge, complex molecules that play many important roles in the body and can be thought of as the “workhorses” of cells. Proteins are required for the structure, function and regulation of the body’s organs and tissues. responsible for protecting them from attack.
Without these proteins, the body’s immune system attacks and destroys the red blood cells, leading to low hemoglobin levels.
This can cause fatiguefatigueExtreme tiredness or exhaustion. Fatigue is one of the most common symptoms of PNH., along with weakness, headaches, shortness of breath and other symptoms, including chest pain and abdominal pain.
PNH develops when there is a change in a part of the body’s DNA, which is called a genetic mutation. The name of the gene that changes is the PIG-A gene.
Because of this mutation, red blood cells are missing critical proteinsproteinsLarge, complex molecules that play many important roles in the body and can be thought of as the “workhorses” of cells. Proteins are required for the structure, function and regulation of the body’s organs and tissues. responsible for protecting them from attack.
Without these proteins, the body’s immune system attacks and destroys the red blood cells, leading to low hemoglobin levels.
This can cause fatiguefatigueExtreme tiredness or exhaustion. Fatigue is one of the most common symptoms of PNH., along with weakness, headaches, shortness of breath and other symptoms, including chest pain and abdominal pain.

What causes PNH?

No one is born with PNH. PNH is “acquired,” which means the genetic mutations responsible for the disease happen during your life. PNH is not something that is contagious, so you can’t give it to anyone else. PNH is closely related to aplastic anemiaaplastic anemiaA rare blood disease that is a known risk factor for PNH. Aplastic anemia occurs when a person’s bone marrow does not make enough new blood cells. Some scientists believe that aplastic anemia weakens the body’s bone marrow, which then affects its ability to produce healthy red blood cells., an autoimmune disease in which the body cannot produce all types of blood cells in sufficient numbers, causing fatigue, infections, bruising and bleeding. Approximately 44% of patients diagnosed with PNH have a history of aplastic anemia.

What are the symptoms?

The symptoms of PNH can vary widely from person to person. Some people have mild symptoms that can be more easily managed. Others have severe symptoms and may need frequent blood transfusionsblood transfusionA medical procedure in which blood from a donor is given to another person through an intravenous (IV) line – a narrow tube placed within the vein of the arm.. The most common symptoms are fatigue, headaches and shortness of breath.

How can you get diagnosed?

PNH can be difficult to diagnose, in part because it’s rare, but also because the symptoms of PNH are similar to those of other illnesses. Blood tests are used to confirm a diagnosis. There are many different tests a doctor may use, each of which helps provide a clue that it may be PNH. One of the most common tests uses a process called flow cytometryflow cytometryThe most common method of testing for PNH, this test confirms whether red blood cells are missing their protective shield. It also calculates the percentage of blood cells impacted by PNH, which is referred to as your clone size. A large clone size means you have a high percentage of blood cells that can be attacked by the complement system, which may lead to more severe symptoms..

Is there a cure?

There is currently no cure for PNH, but some people have had success with a bone marrow transplant or hematopoietic stem cell transplant which replaces unhealthy stem cells with healthy ones. There are also treatments that can help prevent red blood cells from being destroyed. Ongoing scientific research is working to better understand the disease and control the destruction of red blood cells.

I have PNH. What next?

While PNH is rare, there is an active and supportive community here to help. Take a look at our resource center to find advocacy organizations, strategies to navigate the everyday and ways to connect with others who have PNH.

PNH by the numbers

First reported in medical
journals in the late 1800s

Affects ~1 out of every million people

~400-500 new cases
are diagnosed in the U.S.
each year

Impacts both men +
women
of every ethnicity

Diagnosis can take up to 5
years

Many individuals may see more than 5 physicians before getting
diagnosed

Most often
diagnosed at
30-40 years of age

Approximately 44% of patients diagnosed with PNH
have a history of aplastic anemia

Did you know?

The name PNH was based on early observations of people with the disease. PNH stands for Paroxysmal (meaning “sudden and irregular”) Nocturnal (“at night”) Hemoglobinuria (“hemoglobin in urine”). As understanding has advanced, we’ve learned this name can be very misleading, as PNH impacts people at all times of the day, and not all people with PNH have dark-colored urine.