Lymphadenitis is the inflammation and/or enlargement of a lymph node. Lymph node enlargement is common in children. Most cases represent a response to benign, local, or generalized infections (usually viral). Lymphadenitis may affect a single node or a localized group of nodes (regional adenopathy) and may be unilateral or bilateral. The onset and course of lymphadenitis may be acute, subacute, or chronic.

Most children with lymphadenitis exhibit small palpable cervical, axillary, and inguinal nodes. Approximately 5% of these children have palpable suboccipital or postauricular nodes. Palpable supraclavicular, epitrochlear, and popliteal nodes are uncommon, as are mediastinal or abdominal nodes that are detected with radiographic studies.

Pathophysiology

Increased node size may be caused by the following:

Multiplication of cells within the node, including lymphocytes, plasma cells, monocytes, or histiocytes

Infiltration of cells from outside the node, such as malignant cells or neutrophils

Draining of a source of infection by lymph nodes

If the cause of adenopathy is not evident, consider congenital or neoplastic causes.

Treatment

In patients with lymphadenitis, treatment depends on the causative agent and may include the following:

Antimicrobial therapy
Expectant management: Catscratch disease is usually benign and self-limited and generally does not require treatment with antibiotics.
Chemotherapy
Radiotherapy