When you have paroxysmal nocturnal hemoglobinuria (PNH), red blood cells in your body break apart before they should. It happens because the proteins that would normally protect them from your immune system are missing. Your immune system attacks the red blood cells and breaks them down.
You can get this rare blood disease at any age. You aren’t born with it; it happens over time. Although it can be life-threatening, there are treatments to help you feel better and, in some cases, cure it.
Treatments and prognosis for blood diseases vary, depending on the blood condition and its severity.
Blood Disorders Affecting Red Blood Cells
Blood disorders that affect red blood cells include:
Anemia: People with anemia have a low number of red blood cells. Mild anemia often causes no symptoms. More severe anemia can cause fatigue, pale skin, and shortness of breath with exertion.
Iron-deficiency anemia: Iron is necessary for the body to make red blood cells. Low iron intake and loss of blood due to menstruation are the most common causes of iron-deficiency anemia. Treatment includes iron pills, or rarely, blood transfusion.
Anemia of chronic disease: People with chronic kidney disease or other chronic diseases tend to develop anemia. Anemia of chronic disease does not usually require treatment. Injections of a synthetic hormone (Epogen, Procrit) to stimulate the production of blood cells or blood transfusions may be necessary in some people with this form of anemia.
Pernicious anemia (B12 deficiency): An autoimmune condition that prevents the body from absorbing enough B12 in the diet. Besides anemia, nerve damage (neuropathy) can eventually result. High doses of B12 prevent long-term problems.
Aplastic anemia: In people with aplastic anemia, the bone marrow does not produce enough blood cells, including red blood cells. A viral infection, drug side effect, or an autoimmune condition can cause aplastic anemia. Blood transfusions, and even a bone marrow transplant, may be required to treat aplastic anemia.
Autoimmune hemolytic anemia: In people with this condition, an overactive immune system destroys the body's own red blood cells, causing anemia. Medicines that suppress the immune system, such as prednisone, may be required to stop the process.
Thalassemia: This is a genetic form of anemia that mostly affects people of Mediterranean heritage. Most people have no symptoms and require no treatment. Others may need regular blood transfusions to relieve anemia symptoms.
Sickle cell anemia: A genetic condition that affects mostly African-Americans. Periodically, red blood cells change shape, and block blood flow. Severe pain and organ damage can occur.
Polycythemia vera: The body produces too many blood cells, from an unknown cause. The excess red blood cells usually create no problems but may cause blood clots in some people.
Malaria: A mosquito's bite transmits a parasite into a person's blood, where it infects red blood cells. Periodically, the red blood cells rupture, causing fever, chills, and organ damage. This blood infection is most common in Africa; those traveling to Africa are at risk and should take preventive measures. Malaria was eradicated from the U.S. in the 1940s.