Diagnosis

Is the mass a lymph node? Nonlymphoid masses (cervical rib, thyroglossal cyst, branchial cleft cyst or infected sinus, cystic hygroma, goiter, sternomastoid muscle tumor, thyroiditis, thyroid abscess, neurofibroma) occur frequently in the neck and less often in other areas. Is the node enlarged? Lymph nodes are not usually palpable in the newborn. With antigenic exposure, lymphoid tissue increases in volume. They are not considered enlarged until their diameter exceeds 1 cm for cervical and axillary nodes and 1.5 cm for inguinal nodes. Other lymph nodes usually are not palpable or visualized with plain radiographs. What are the characteristics of the node? Acutely infected nodes are usually tender. There may also be erythema and warmth of the overlying skin. Fluctuance suggests abscess formation. Tuberculous nodes may be matted. With chronic infection, many of these signs are not present. Tumor-bearing nodes are usually firm and nontender and may be matted or fixed to the skin or underlying structures.

Is the lymphadenopathy localized or generalized? Generalized adenopathy (enlargement of >2 noncontiguous node regions) is caused by systemic disease (Table 484-1) and is often accompanied by abnormal physical findings in other systems. In contrast, regional adenopathy is most frequently the result of infection in the involved node and/or its drainage area (Table 484-2). When due to infectious agents other than bacteria, adenopathy may be characterized by atypical anatomic areas, a prolonged course, a draining sinus, lack of prior pyogenic infection, and unusual clues in the history (cat scratches, tuberculosis exposure, venereal disease). A firm, fixed node should always raise the question of malignancy, regardless of the presence or absence of systemic symptoms or other abnormal physical findings.

Table 484-1 DIFFERENTIAL DIAGNOSIS OF SYSTEMIC GENERALIZED LYMPHADENOPATHY

CMV, cytomegalovirus; EBV, Epstein-Barr virus; HIV, human immunodeficiency virus; JRA, juvenile rheumatoid arthritis (Still disease); SLE, systemic lupus erythematosus.

From Kliegman RM, Greenbaum LA, Lye PS: Practical strategies in pediatric diagnosis and therapy, ed 2, Philadelphia, 2004, Elsevier, p 863.

Treatment

Evaluation and treatment of lymphadenopathy is guided by the probable etiologic factor, as determined from the history and physical examination. Many patients with cervical adenopathy have a history compatible with viral infection and need no intervention. If bacterial infection is suspected, antibiotic treatment covering at least streptococci and staphylococci is indicated. Those who do not respond to oral antibiotics, as demonstrated by persistent swelling and fever, require IV antistaphylococcal antibiotics. If there is no response in 1-2 days or if there are signs of airway obstruction or significant toxicity, CT or ultrasound of the neck should be obtained. If pus is present, it may be aspirated, with CT or ultrasound guidance, or if it is extensive, may require incision and drainage. Gram stain and culture of the pus should be obtained. The sizes of involved nodes should be documented before treatment. Failure to decrease in size within 10-14 days also suggests the need for further evaluation, which may include a complete blood cell count with differential; Epstein-Barr virus, cytomegalovirus, Toxoplasma, and cat scratch disease titers; antistreptolysin O or anti-DNAse serologic tests; tuberculin skin test; and chest radiograph. If these studies are not diagnostic, consultation with an infectious disease or oncology specialist may be helpful. Biopsy should be considered if there is persistent or unexplained fever, weight loss, night sweats, supraclavicular location, mediastinal mass, hard nodes, or fixation of the nodes to surrounding tissues. Biopsy may also be indicated if there is an increase in size over baseline in 2 wk, no decrease in size in 4-6 wk, or no regression to “normal” in 8-12 wk, or if new signs and symptoms develop.