PNH is an acquired disease that destroys an important part of the blood, the red blood cells.1 Red blood cells develop in the bone marrow and are important because they help deliver oxygen.
With PNH, some or all of the body’s red blood cells (RBCs) are destroyed in a process called ‘haemolysis.’ In PNH, haemolysis is taking place at all times and at high rates, putting people with PNH at risk. Haemolysis is the main cause of the symptoms with PNH.1-4
Haemolysis is the cause of the symptoms of PNH, including the most serious complications.1
When red blood cells burst, they release haemoglobin, a protein responsible for carrying oxygen in the blood. While haemoglobin is good for the body while inside the red blood cell, it causes harm when it's outside the cell. Over time the build-up of free haemoglobin can cause serious health problems.1
The measurement of haemolysis - LDH
Lactate dehydrogenase (LDH) is a molecule inside red blood cells that, can be measured in a blood test and provides a guide to the rate of haemolysis taking place. A high LDH measure indicates that a large number of red blood cells have been destroyed. For people with PNH, regular measurement of LDH is important.5
A major concern with PNH is that its effects are not always noticeable, so serious health risks can occur without warning.4 If left untreated, PNH can lead to:
"PNH" stands for Paroxysmal Nocturnal Haemoglobinuria
The disease was called this before much was known about it. Today, although more is known about the disease, doctors still call it PNH.3
But the name is a little misleading! Here’s why:
The signs and symptoms of PNH can be silent and unpredictable. They affect each person differently and can change from day to day. Fatigue, often severe, is a common symptom of PNH.21
PNH is like an iceberg – what can not be seen or felt can be the most damaging21
Someone with PNH may experience one or more of the symptoms listed above frequently or just occasionally. However, they may not immediately experience other complications such as blood clots and kidney disease.
Due to the wide range of symptoms associated with PNH, it is not unusual for months or years to pass before the correct diagnosis is established.17
How is PNH diagnosed?
PNH is diagnosed by a special test called ‘Flow Cytometry’.16 Doctors apply this test to a sample of blood to find out whether blood cells are affected by PNH.
What is clone size?
Clone size refers to the percentage of red blood cells affected by PNH. The larger the clone size, the greater the number of red blood cells that are affected. However, even small clone sizes can lead to PNH-related health symptoms.14
Early diagnosis is important in reducing the rate of haemolysis16,18
Reducing haemolysis as soon as possible may help in limiting the damage it can cause.16,18
Fortunately much has been learnt about PNH in recent years and there have been advances in treatment options. These new discoveries have helped doctors and people with PNH proactively manage the disease, and helped people with PNH return to normal life.10
If you have been diagnosed with PNH you can expect close, lifelong medical attention and support. Your GP and haematologist are key to ongoing care. Other medical professionals, such as nurses, are often involved too. To help ensure that the best care is provided at all times, you will need to keep in close contact with your medical team, alerting them promptly to any changes in health.
Treatment decisions are based on your symptoms, the extent of any organ damage and the results of regular monitoring for signs of the disease.
Anticoagulants may be prescribed to reduce the risk of blood clots. Anticoagulants have no effect on the haemolysis that causes the symptoms of the disease.15
Blood transfusions may be given to help restore a healthy level of red blood cells. Blood transfusions do not treat the haemolysis, that causes the symptoms of the disease.15
Better understanding of the dysfunction underlying PNH has led to the development of treatment that addresses the underlying cause of the disease.6,19
There are a number of important regular blood tests that can help show how well PNH is being controlled.
Regular visits to the GP are important for monitoring general health and visits to a haematologist every three to six months are recommended.
PNH is a serious disease and living with it can be stressful. Understanding the disease can help in the management of signs and symptoms. Keeping track of symptoms is important.
Living with PNH can be difficult as the disease is serious, but often silent. Here are some suggestions that may make day-to-day living easier.
The following section offers tips that may help you to talk about PNH to family and friends.
Talking about your disease may help make life easier. For people who have been diagnosed recently, here’s why talking to others about PNH might be important.
PNH Support Association of Australia Inc. (PNHSAA) http://www.pnhsaa.org.au The association’s aim is to support PNH patients and their loved ones to manage their condition positively by providing access to accurate information, practical resources and a support network. They also provide opportunities to meet with other patients and caregivers to reduce the isolation often experienced by people with rare diseases.
Rare Voices Australia (RVA) http://www.rarevoices.org.au RVA is a national organisation is an advocate on behalf of people who live with a rare disease. RVA works with governments, researchers, clinicians and industry to promote research, diagnosis, treatment and services for all rare diseases in Australia.
PNH Symptom Tracker
Click here to download the PNH Symptom Tracker.