Paroxysmal nocturnal hemoglobinuria(PNH) is an acquired, potentially life-threatening disorder.
It causes the red blood cells to break apart, a process calledhemolysis.
This releases hemoglobin from the red blood cells into the urine, which turns dark or blood-colored.
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At first, the disease was thought to occur in bursts called paroxysms, and only at night.
It was later discovered that the hemolysis is a constant process and it happens in the day as well.
This article offers an overview of PNH, including symptoms and possible causes.
An earlier name for PNH was Marchiafava-Micheli syndrome.
Types of PNH
PNH affects people of all sexes and ethnic backgrounds.
It can occur at any age, but most people are diagnosed while they are in their 30s.
PNH has three main types.
They each cause a different pattern of symptoms.
Hemolysis
Thrombosis
Symptoms of thrombosis depend on where the blood clot occurs.
Clots in the skin cause raised, painful, red lumps over large areas, such as the back.
The change occurs randomly in a single stem cell, which then multiplies and expands, causing the disease.
The reason PNH cells expand and multiply is not fully known.
One likely cause is an autoimmune response that leads to bone marrow failure.
PNH will occur in most people diagnosed with acquiredaplastic anemia.
More than 10 out of every 100 people with aplastic anemia will develop PNH.
For this reason, the process will involve several types of tests.
Blood Tests
Flow Cytometry
Aflow cytometrytest is considered the gold standard for diagnosing PNH.
This blood test can separate and analyze various components of blood.
It reveals whether two key proteins, CD55 and CD59, are missing from the surface of blood cells.
The sample is examined under a microscope to look at how well the marrow is producing blood cells.
Treatment
Treatments for PNH cannot cure the disorder.
Theymanage the diseaseand/or treat specific symptoms.
These treatments include:
The only potential cure for PNH is abone marrow transplant.
In which stem cells are removed from the bone marrow and replaced with healthy bone marrow from a donor.
Bone marrow transplants are serious and risky procedures.
Prognosis
The course and severity of PNH varies.
People with a mild case are likely to have a normal lifespan.
Those with PNH alongside aplastic anemia or MDS may have a shorter lifespan.
Blood clots are the main cause of severe complications and death in people with PNH.
Precautions
Living with PNH requires taking certain precautions.
If you have anemia, this shortage can cause chest pain and fatigue.
Before you travel by air or go to a high-altitude spot, talk to your healthcare provider.
They may want to check your red cell count and adjust treatments to prevent a reaction.
Pregnancy
Having PNH can put both the mother and baby at risk.
Risks to the mother include blood clots,preeclampsia, and a need for blood transfusions.
Risks to the baby include prematurity, low birth weight, stillbirth, and delayed growth and development.
If you are considering pregnancy, find an obstetrician who specializes in high-risk births.
Surgery
Surgery can increase your risk of blood clots and cause serious bleeding if you have PNH.
Summary
Although PNH is rare, it is a serious chronic disease.
They are increasing life expectancy, and research on the disease continues.
If you are interested, the National Organization for Rare Diseases can provide information on participating in aclinical trial.
Coping with PNH may take an emotional toll as well as a physical one.
Resources like those from theAAMDS Foundationcan help you find specialists, support groups, financial help, and more.
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