Warm autoimmune haemolytic anaemia (wAIHA) is an autoimmune disease where the body’s immune system produces autoantibodies that attack and destroy its own red blood cells at warm temperatures.^1,2 These autoantibodies are active at regular body temperature and higher (37-40˚C). There is also a different condition where the red blood cell destruction occurs at cold temperatures (cold autoimmune haemolytic anaemia). Red blood cells usually have a life span of 120 days; however, in autoimmune haemolytic anaemias, the red blood cells are destroyed as fast as they are produced, leaving very few in the bloodstream. Symptoms of wAIHA can be mild or life threatening and require long term management.

Warm autoimmune haemolytic anaemia can occur without an underlying cause (known as primary or idiopathic wAIHA) or can occur as a result of other conditions (secondary wAIHA) such as other autoimmune disorders and cancers involving blood cells (haematologic malignancies).^1,2 The treatment of primary and secondary wAIHA may differ. 

Synonyms: wAIHA, wAHA, warm antibody autoimmune haemolytic anaemia, autoimmune hemolytic anemia, primary/idiopathic autoimmune haemolytic anaemia, autoimmune haemolytic anaemia syndrome.^{1, 2}

ORPHA:90033 Autoimmune hemolytic anemia, warm type

ICD-11: 3A20.0 Autoimmune haemolytic anaemia, warm type

Universal rare disease classifications provide a common language for recording, reporting and monitoring diseases. Please visit the Rare Disease Classifications page for more information about these internationally recognised classifications.

The signs and symptoms of wAIHA can vary from mild to severe.³ They include weakness, fatigue, dizziness, headaches, pale skin colour (pallor), rapid heartbeat (tachycardia), shortness of breath (dyspnoea), dark urine, backache, and yellowing of skin and eyes (jaundice).^1,2,4,5 There may also be confusion, enlargement of the spleen (splenomegaly), and signs of heart failure.

Individuals with wAIHA may have an increased risk of developing blood clots, strokes, and heart issues.³

Please speak to your medical team to learn more about the signs and symptoms of wAIHA.

Rare diseases are often serious and progressive, exhibiting a high degree of symptom complexity, leading to significant disability. Majority of the estimated two million Australians living with a rare disease meet the Australian Government’s definition for disability (in accordance to the Australian Public Service Commission and Australian Bureau of Statistics), and many experience severe and permanent disability impacts. If you or someone you care for is experiencing disability-related impacts from a rare condition, please speak with a health or disability professional for advice. Information about relevant disability support can be found at the RARE Portal’s Disability Support Information page.

wAIHA is an autoimmune condition in which the body’s immune system produces antibodies that target its own red blood cells.^1,2 These are known as autoantibodies. At warm temperatures in the body, these autoantibodies stick to red blood cells. This causes the red blood cells to be recognised as abnormal and destroyed by immune cells.

Some people may spontaneously start producing excessive amounts of wAIHA autoantibodies. It is not known what causes this, however in some people it has been associated with prior infections, transplants or transfusions.³ In other cases, wAIHA may arise due to another condition (secondary wAIHA).^3,4 These conditions include lymphoproliferative disorders such as chronic lymphatic leukemia, lymphomas, other autoimmune disorders such as lupus, immunodeficiencies such as Kabuki syndrome, and Evans syndrome.

Haemolytic anaemia may be considered based on a clinical examination of the symptoms and standard blood tests showing a high proportion of young compared to old red blood cells, and misshapen red blood cells.^3,6,7 More blood or urine tests may also be performed to look for other signs of red blood cell destruction (haemolysis). These tests may include complete blood count (CBC), a bilirubin test, haptoglobin test, and a lactate dehydrogenase (LD) test.

Once haemolytic anaemia is confirmed, a direct antiglobulin test (DAT, also known as Coomb’s test) can be used to determine if there are autoantibodies sticking to red blood cells. This test can be used to diagnose warm autoimmune haemolytic anaemia (wAIHA) and distinguish it from cold autoimmune haemolytic anaemia (cAIHA) (which involves a different type of antibody).^3,7 Following diagnosis with wAIHA, more tests are usually done to look for any underlying conditions, which would indicate that it is secondary wAIHA.^3,7

More detailed information on internationally recommended diagnostic criteria can be found at:

• Diagnosis and treatment of autoimmune hemolytic anemia in adults: Recommendations from the First International Consensus Meeting developed by a group of international experts from Europe and USA, published in 2020.

• The diagnosis and management of primary autoimmune haemolytic anaemia developed by the British Society for Haematology in collaboration with UK based experts, published 2016.

A differential diagnosis can rule out other conditions that have similar symptoms, such as other forms of autoimmune haemolytic anaemia (cold, mixed-type and drug-induced), Evans syndrome, paroxysmal nocturnal hemoglobinuria, hereditary spherocytosis and thrombotic microangiopathies.^1,2

Please speak to your medical team to learn more about the available diagnostic pathways for warm autoimmune haemolytic anaemia.

There is currently no curative treatment for wAIHA. Treatment is targeted at managing symptoms (symptomatic management) and involves a multidisciplinary care team. This may include use of medications such as steroids and/or biological medications to suppress the immune system.^1,3,4 In severe cases, blood transfusions may also be needed to immediately supply healthy red blood cells to the body.^7,9,10 In life threatening cases with sudden onset, the spleen may be surgically removed as the spleen is where many red blood cells are destroyed in wAIHA.⁸

In secondary wAIHA, treatment of the underlying condition usually reduces the severity of the anaemia.^4,11

Some individuals with wAIHA have an increased risk of thrombosis (blood clot in artery or vein) and there may be strategies to manage this risk.³

Please speak to your medical team to learn more about the possible treatment or management options for your condition. Treatment will depend on an individual’s specific condition and symptoms. It is also important to stay connected to your medical team so that you can be made aware of any upcoming clinical trial opportunities.

Clinical care for rare diseases often involves a multidisciplinary team of medical, care and support professionals. Please note that the information provided here is as a guide and that RVA does not necessarily monitor or endorse specific clinics or health experts.

Healthcare professionals involved in the treatment of wAIHA may include general practitioners (GP), paediatricians, haematologists, immunologists and rheumatologists.³ The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here.

We are not aware of any clinical care guidelines for wAIHA in Australia. If you know of any relevant care guidelines, please let us know via the Contribute page.

The following guidance is available from international experts outside Australia; however, there may be information that is not relevant or applicable to the Australian context, and may not be up to date:

• Diagnosis and treatment of autoimmune hemolytic anemia in adults: Recommendations from the First International Consensus Meeting; developed by a group of international experts, published in 2020.
• The diagnosis and management of primary autoimmune haemolytic anaemia developed by the British Society for Haematology in collaboration with UK based experts, published in 2016.
• Guidelines on the management of drug-induced immune and secondary autoimmune, haemolytic anaemia developed by the British Society for Haematology in collaboration with UK based experts, published in 2017.

Individuals living with rare diseases may have complex medical issues and disabilities, which are not always visible. It is often useful to refer to their medical history as well as personal information such as a medical card, doctor’s letter, or if available, a rare disease passport, for relevant information.

The following guidance includes information for emergency situations and is available from international experts outside Australia; however, there may be information that is not relevant or applicable to the Australian context, and may not be up to date:

• Diagnosis and treatment of autoimmune hemolytic anemia in adults: Recommendations from the First International Consensus Meeting developed by a group of international experts, published in 2020.
• Emergency Transfusion Guidelines for Autoimmune Hemolytic Anemia developed in Canada, published in 2005.

There are specific considerations around participating in rare disease research, including clinical trials. It is important to be mindful of issues such as data privacy, research ethics, consent and differences in research regulations between Australia and other countries.

If you are interested in finding clinical trials for your condition, please visit the following websites; however, there may not be any clinical trials available:

• Australian Clinical Trials
• ClinicalTrials.gov

It is best to discuss your interest in any clinical trials with your medical team to determine suitability and eligibility.

Please note that RVA does not necessarily monitor or endorse each group/organisation’s operational governance and activities.

There are currently no known organisations in Australia for this rare disease. If you know of any rare disease organisation/s supporting people living with wAIHA, please let us know via the Contribute page. If you are interested in starting an Australian organisation for people living with wAIHA, please see Engaged, Ethical and Effective: A Guide for Rare Disease Organisation Leaders in Australia.

International Organisation:

wAIHA Warriors (United States of America)

Website: https://waihawarriors.org

Please note that RVA does not monitor or endorse each group/organisation’s operational governance and activities. When engaging with a group, please consider the information on the RARE Portal’s Finding Helpful Peer and Community Supports page.

wAIHA varies between individuals, and each person’s experience is unique.

If you would like to share your personal story with RVA, please visit the Rare Voices Australia: Share Your Story page. RVA will consider your story for publishing on our website and inclusion on the RARE Portal.

For information on available government and social services that provide support for individuals with a rare disease, please visit the National and State Services pages.

People living with a rare disease, including families and carers, often face unique challenges such as diagnostic delays, misdiagnoses, limited treatment options, and limited access to rare disease specialists and support. These challenges may impact people’s emotional wellbeing and quality of life. Many people find it helpful to seek mental health and wellbeing support to cope with ongoing stress and uncertainty. Connecting with people who have shared experiences through a support group may also be helpful. Information about relevant mental health and wellbeing support can be found at:

• Mental Health and Wellbeing Support for Australians Living with a Rare Disease
• The National and State Services pages underneath the ‘Mental Health’ sections listed

Further information on wAIHA can be found at:

• health direct: Anaemia
• Genetic and Rare Diseases (GARD) Information Center: Autoimmune hemolytic anemia, warm type
• National Organization for Rare Disorders (NORD): Warm Autoimmune Hemolytic Anemia

Online Mendelian Inheritance in Man (OMIM): #205700 Anemia, Autoimmune Hemolytic

Orphanet: Autoimmune hemolytic anemia, warm type

Human Phenotype Ontology (HPO): Autoimmune hemolytic anemia

This page has been developed by Rare Voices Australia (RVA)‘s RARE Portal team.  

If you are aware of any additional information that may benefit stakeholders with an interest in this page, or if you notice any broken links or inaccurate information, please let us know via the Contribute page.