An immune system condition called Castleman disease affects the lymph nodes. In Castleman disease, the lymph nodes become enlarged and abnormal, causing a number of symptoms and complications. Lymph nodes fight infections and filter harmful substances from the body.
There are two main types of Castleman disease: unicentric and multicentric. Unicentric Castleman disease affects only one lymph node or a group of nearby lymph nodes in one part of the body. Castleman disease that is multicentric affects multiple lymph nodes in various parts of the body. Both types have varying symptoms, causes, and treatments.
The exact causes of Castleman disease are not well understood. However, some factors that may be involved are:
Kaposi's sarcoma, a type of cancer affecting the skin and internal organs, is also caused by infection with the human herpes virus 8 (HHV-8). The human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS) are more likely to infect people with HHV-8.
Overproduction of a protein called interleukin-6 (IL-6), which regulates the immune system and inflammation. IL-6 may stimulate the growth of lymph node cells and cause symptoms of Castleman disease.
Genetic mutations or abnormalities that affect the immune system or the lymph node cells.
Other underlying conditions that affect the blood or the immune system, such as POEMS syndrome, which is a rare disorder that causes nerve damage, organ enlargement, skin changes, and other problems.
The symptoms of Castleman disease depend on the type and the severity of the condition. Some people with unicentric Castleman disease may not have any symptoms, while others may experience:
A lump or swelling in the neck, chest, abdomen, or groin area, where the affected lymph node is located.
Pressure or pain in the affected area, especially if the enlarged lymph node compresses nearby organs or nerves.
Fever, night sweats, weight loss, fatigue, or loss of appetite.
People with multicentric Castleman disease usually have more severe and widespread symptoms, such as:
Enlargement of multiple lymph nodes in different parts of the body, which may be visible or palpable.
Enlargement of the liver, spleen, or other organs, which may cause abdominal discomfort or distension.
Anemia, which is a low level of red blood cells that carry oxygen in the blood. This may cause weakness, paleness, shortness of breath, or dizziness.
Low levels of platelets, which are blood cells that help with clotting. This may cause easy bruising, bleeding, or petechiae (tiny red spots on the skin).
Low levels of white blood cells, which are blood cells that fight infections. This may increase the risk of infections, such as pneumonia, herpes, or fungal infections.
Nerve damage, which may cause numbness, tingling, pain, or weakness in the arms, legs, or other parts of the body.
Skin rash, which may be itchy, red, or scaly.
Fluid accumulation in the lungs, which may cause coughing, wheezing, or difficulty breathing.
Fluid accumulation in the legs, which may cause swelling, pain, or reduced mobility.
Kidney problems, which may affect the urine output, blood pressure, or electrolyte balance.
Heart problems, which may affect the heart rate, rhythm, or function.
The diagnosis of Castleman disease is based on the medical history, physical examination, and various tests, such as:
Blood tests, which can measure the levels of blood cells, proteins, antibodies, and other substances in the blood. Blood tests can also detect the presence of HHV-8 or HIV infection.
Urine tests, which can check for signs of kidney problems or infections.
The enlarged lymph nodes and other organs can be visualized with imaging tests such as ultrasound, computed tomography (CT) scans, magnetic resonance imaging (MRI) scans, and positron emission tomography (PET) scans.
A biopsy involves examining a small sample of tissue under a microscope to confirm the diagnosis of Castleman disease and rule out other conditions, such as cancer or infection.
There are various treatment options for Castleman disease, depending on its type, symptoms, and overall health. The main goals of treatment are to shrink enlarged lymph nodes, reduce symptoms, and prevent complications.
Surgical removal of the affected lymph node or lymph node group, along with some surrounding tissue, is usually the preferred treatment for unicentric Castleman disease.
For multicentric Castleman disease, medications are the main treatment. Among the medications that may be used are corticosteroids, rituximab, tocilizumab, siltuximab, antivirals, or chemotherapy. These medications suppress the immune system, block the action of IL-6, or target the HHV-8 virus. Although medications can reduce the symptoms of multicentric Castleman disease, they may not completely cure the condition.
Using high-energy rays to destroy abnormal cells, radiation therapy can shrink enlarged lymph nodes or treat complications like nerve compression and organ damage.
During a stem cell transplant, a donor's healthy stem cells are replaced in damaged bone marrow. When multicentric Castleman disease patients do not respond to other treatments or have life-threatening complications, stem cell transplantation may be considered.
There is no known way to prevent Castleman disease, as the causes are not fully understood. However, some possible measures that may reduce the risk or the severity of the condition are:
Practice safe sex, use condoms, avoid sharing needles, and get tested regularly for HHV-8 and HIV, which are associated with multicentric Castleman disease.
In addition to eating a balanced diet, drinking enough water, getting enough sleep, exercising regularly, managing stress, and avoiding smoking and drinking alcohol, maintaining a healthy lifestyle can help boost the immune system and prevent infections.
By following the treatment plan, Castleman disease can be controlled and complications can be prevented. This includes taking the prescribed medications, keeping in touch with your healthcare provider, and reporting any new or worsening symptoms.
