Hairy Cell Leukemia Clinical Presentation

Updated: Oct 25, 2022
  • Author: Emmanuel C Besa, MD; Chief Editor: Sara J Grethlein, MD, MBA, FACP  more...
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The most common symptoms and presenting complaints in hairy cell leukemia are weakness and fatigue due to anemia. Approximately one third of patients have bleeding from thrombocytopenia, and another third have fever and infections from neutropenia. 

Symptoms related to organ infiltration of the reticuloendothelial system may occur. Abdominal discomfort from an enlarged spleen is present in one quarter of patients. 

Some patients may present with weight loss, fever, and night sweats, similar to other lymphoproliferative disorders.

Hairy cell leukemia is associated with gram-positive and gram-negative bacterial infections, as well as atypical mycobacterial and invasive fungal infections. Other opportunistic infections, such as Legionella, toxoplasmosis, and listeriosis, have been reported.

Hairy cell leukemia is associated with other systemic immunologic disorders including the following:

  • Scleroderma
  • Polymyositis
  • Polyarteritis nodosa
  • Erythematous maculopapules
  • Pyoderma gangrenosum

Other uncommon conditions may be associated with hairy cell leukemia, such as acquired factor VIII antibodies, paraproteinemia, and systemic mast cell disease.


Physical Examination

Splenomegaly is the most common physical finding in hairy cell leukemia. It is present in virtually every patient with the disease and it is massive in more than 80% of patients. Hepatomegaly with mild liver function abnormalities is found in 20% of cases, and lymphadenopathy is found in 10%.

A low-grade fever is part of the disease, but it may alsobe due to an infection from the resulting neutropenia. In more than half of the cases, it is from a gram-negative organism. Atypical mycobacterial infections are common. Disseminated fungal infections and Pneumocystis jiroveci pneumonia may occur in some cases of hairy cell leukemia.

Peripheral lymphadenopathy is uncommon; fewer than 10% of patients present with peripheral nodes larger than 2 cm in diameter. However, internal adenopathy may develop after a prolonged disease course and was found in 75% of patients at autopsy.