Symptoms of Hairy Cell Leukemia

Patients with hairy cell leukemia often have a slow onset of symptoms and may not be diagnosed for several months or even years of illness. The symptoms of hairy cell leukemia can be divided into those related to the effects due to bone marrow involvement, effects due to other organ involvement, and secondary complications due to infections or autoimmunity.

Bone Marrow Disease

Hairy cell leukemia is thought to develop in the bone marrow and as the hairy cell leukemia progresses, the normal function of the bone marrow decreases. The normal function of the bone marrow is to produce white blood cells, red blood cells (that carry hemoglobin) and platelets.

Decreased hemoglobin, which can cause anemia, can develop slowly and drop to very low levels. This can result in marked fatigue and weakness, shortness of breath, and/or dizziness.

A decrease in the white blood cells (these cells make up the immune system) can lead to recurrent infections such as pneumonia, bronchitis, etc.

The platelets can decrease to life-threatening levels, where severe spontaneous bleeding can occur. Patients may notice nosebleeds or gum bleeding, increased bruising, or even severe bleeding from their stomach.

Organ Involvement

Even though hairy cell leukemia develops in the bone marrow, it commonly travels to other organs as well. A common finding in patients is an enlarged spleen two to three times normal size. This can cause pain on the left side where the spleen is located, early feeling of fullness in the stomach, and in some cases severe pain.

The liver may also be involved, leading to pain on the right side, abnormalities of the liver function, or accumulation of fluid in the abdomen called ascites. Although uncommon, hairy cells can invade the bones and cause bone destruction with severe pain. Lymph nodes may be affected and enlargement can cause pain, whether in nodes in the neck or the abdomen. Rarely, there can be involvement in the brain causing headaches or abnormalities of brain function.

Secondary Complications

Patients with hairy cell leukemia have disturbed immune systems due to changes in their blood cells. Infections due to fungus and viruses can affect the skin, lungs, liver, or brain. Symptoms from these can include fever, cough, rashes, headaches or confusion.

Autoimmune disease may be seen in up to one-third of patients and usually causes inflammation of blood vessels or joints. Patients may have increased joint pain and swelling, unusual skin rashes, fever and/or weight loss. This can occur at the beginning or any time after diagnosis.


Patients with hairy cell leukemia may develop many different symptoms due to their illness, and patients and doctors should be aware of the many associated problems that can occur. The slow onset of the disease and its rarity may lead to the accurate diagnosis being missed or delayed. It may be helpful to consult a hairy cell leukemia expert at one of our Centers of Excellence.