Lymphatic obstruction is blockage of the lymph nodes, the vessels that drain fluid from tissues throughout the body and allow immune cells to travel where needed.

Lymphatic obstruction is also called lymphedema, which means swelling of the lymph passages.

There are many causes of lymphatic obstruction, including:

• Skin infections such as cellulitis (more common in obese patients)
• Parasitic infections such as filariasis
• Injury (trauma)
• Tumors
• Surgery
• Radiation therapy

In Western societies, one of the most common causes of lymphedema is mastectomy with axillary dissection (removal of the breast and underarm lymph tissue for breast cancer). This can cause lymphedema of the arm in 10-15% of patients. This occurs because the lymphatic drainage of the arm passes through the axilla (armpit), and tissue in the axilla has been removed during mastectomy.

Rare forms of congenital (present from birth) lymphedema may result from problems in the development of the lymphatic vessels.

Persistent (chronic) swelling, usually of the arm or leg

The doctor will perform a physical exam and ask questions about your medical history.

The following tests may be performed:

• Lymphangiography
• Lymphoscintigraphy
• MRI