Lymphadenopathy may be classified according to distribution into 2 groups localized lymphadenopathy and generalized lymphadenopathy.

Depending upon the involvement of the lymph nodes, lymphadenopathy is classified into 2 groups, generalized and localized:^[1]

• Localized lymphadenopathy: localized adenopathy occurs in contiguous groupings of lymph nodes. In discrete anatomical regions, lymph nodes are distributed, and their enlargement represents their location’s lymphatic drainage. Tender or non-tender, fixed or mobile, and discreet or “matted” together can be the nodes themselves. 75 percent of all lymphadenopathies are localized, with over 50% seen in the region of the head and neck.

• Generalized lymphadenopathy: generalized lymphadenopathy involves lymphadenopathy in 2 or more non-contiguous sites. due to generalized infection all over the body e.g. influenza.
• Persistent generalized lymphadenopathy (PGL): persisting for a long time, possibly without an apparent cause.
• Dermatopathic lymphadenopathy: lymphadenopathy associated with skin disease. Tangier disease (ABCA1 deficiency) may also cause this.

Lymphadenopathy may be classified as follows:

• Location:
  • Tracheobronchial lymph nodes.
  • Mediastinal lymphadenopathy
  • Bilateral hilar lymphadenopathy
• Dermatopathic lymphadenopathy: lymphadenopathy associated with skin disease.
• Malignancy: Benign lymphadenopathy is distinguished from malignant types which mainly refer to lymphomas or lymph node metastasis.

• Extent:
  • Localized lymphadenopathy: due to localized spot of infection
  • Generalized lymphadenopathy: due to systemic infection of the body. In some cases, it may persist for prolonged periods possibly without an apparent cause

• Size, where lymphadenopathy in adults is often defined as a short axis of one or more lymph nodes is greater than 10mm.^[2][3]