Warm autoimmune haemolytic anaemia (WAHA)
Warm autoimmune haemolytic anaemia (WAHA) is a form of autoimmune haemolytic anaemia characterised by the presence of anti-erythrocyte autoantibodies also called "warm autoantibodies", which are most active at temperatures between 37 and 40 ° C.
This disease is more common in women than in men.
Symptoms of WAHA are the same as those of anaemia: fatigue, shortness of breath during physical activity, and more rarely, the presence of jaundice (a condition that causes the skin and mucous membranes to turn yellow) and dark urine in the event of rapid destruction of red blood cells (called haemolysis).
In severe cases fever, chest pain, loss of consciousness or heart failure may occur.
Haemolysis mainly takes place in the spleen, the volume of which increases, causing moderate splenomegaly (enlarged spleen).
Causes and risk factors
There exist two possible causes of WAHA: half of the cases are idiopathic, also called primary (the cause of the development of the disease is not known); the other half is related to an underlying condition, most often chronic lymphocytic leukemia (CLL) or another autoimmune disease, such as Systemic Lupus Erythematosus, for example.
WAHA is the most common form of AHA; it represents about 75% of all cases.
The diagnosis is mainly based on clinical signs and lab values. A blood test is necessary to search for biological abnormalities. Autoantibody detection also confirms the diagnosis.
The main treatment for WAHA is corticosteroid therapy. Corticosteroids reduce inflammation and modulate the immune system, the malfunction of which provokes the symptoms. If this treatment fails, splenectomy (surgical removal of the spleen) may be an alternative.
In severe and chronic refractory cases, immunosuppressants may be considered. Rituximab, a monoclonal antibody, can also have an effect on the immune system.
In case of treatment by corticosteroids, it is necessary to include antibiotics in the treatment regimen (most often cotrimoxazole), to fight possible pulmonary infections.
Living with the disease
Healthcare professionals involved in the management of WAHA are a GP, a specialist physician (usually an internist or a haematologist), and a pathologist in charge of blood tests.
The follow-up care plan involves medical appointments 3 to 4 times a year during the active periods of the disease, and 1 or 2 times a year during the less active periods.
In addition to doctor’s appointments, regular blood tests (to monitor the level of hemoglobin and haemolysis parameters) help to evaluate treatment efficiency and to monitor the absence of relapse.
Published 3 Dec 2021