Paroxysmal nocturnal hemoglobinuria (PNH)

Causes and Risks:
The exact cause of this rare disorder is unknown. It is thought to be a disorder of the stem cell (the immature form of blood cells) in which a sensitivity to complement (a substance produced by the immune system) occurs in the cell membrane. The disease may affect people of any age, but it is most common in the 30 to 40 age group. Red blood cell, white blood cell and platelet counts may be low. Urine may be red or brown in the morning, signifying the breakdown of red blood cells during the night with release of hemoglobin into the circulation and then the urine. Blood clots may form in some people. The disease may progress to aplastic anemia or acute myelogenous leukemia . Risk factors except for prior aplastic anemia) are unknown. The incidence is 1 out of 100,000 people.

Prevention:
There is no known way to prevent this disorder.

Symptoms:



Signs and Tests:
A physical examination may show an enlarged spleen and liver.

This disease may also alter the results of the following tests:



Treatment:
The objective of treatment is to stimulate new red blood cell formation. The administration of iron, folic acid , and androgens usually achieves this goal. Some people respond to steroid therapy. Eventually, blood transfusions are required. Anticoagulation therapy may be required to prevent clot formation. A few patients have been successfully treated with a bone marrow transplant .

Prognosis:
The outcome is varies. Most people do not survive for more than 10 years after diagnosis. Death may be related to complications from blood clot formation (thrombosis).

Complications:



Call Your Healthcare Provider:
Call your health care provider if blood in urine is present.

Call your health care provider if symptoms worsen or do not improve with treatment.

Call your health care provider if new symptoms develop.