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FIGURE 47.2 Lymph nodes of the body. (Reprinted with permission from Anderson MK. Foundations of
Athletic Training . 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2012.)

A third commonly encountered cause of cervical adenopathy in children and
adolescents is infectious mononucleosis caused by EBV, a herpes virus. EBV typically
causes bilateral anterior and posterior cervical lymph node swelling that is tender to
palpation. Nodes may be large and usually peak in size over the first week of illness,
gradually subsiding over the next few weeks. The classic presentation of mononucleosis
is a prodrome of malaise, headache, and elevated temperature prior to the development of
an exudative pharyngitis, tender cervical adenopathy, and fever. Splenomegaly, abdominal
pain, and anorexia may be present. Facial edema can accompany significant cervical
adenopathy, presumably reflecting obstructed lymphatic drainage. Younger children with
EBV infection may present less typically, with fever alone, symptoms of an upper


respiratory infection, or abdominal complaints. Diagnosis of infectious mononucleosis
can be made in adolescents with the detection of a positive heterophile–agglutinating
antibody (e.g., monospot); however, the test may be falsely negative early in the disease
course or in young children. Antibody titers directed to specific EBV antigens may be
necessary to confirm the diagnosis. In addition, a complete blood count with differential
(CBC/d) often shows a lymphocytosis with a large proportion of atypical lymphocytes.
In contrast to the acute cervical adenopathy seen with reactive lymphadenopathy,
lymphadenitis, and infectious mononucleosis, there are a number of infectious agents that
cause a more indolent course of cervical lymph node swelling. In children, the most
common infections causing a subacute or chronic cervical adenopathy include Bartonella
henselae, nontuberculous strains of mycobacterium, and Mycobacterium tuberculosis.
Catscratch disease is a lymphocutaneous syndrome that follows inoculation of B.
henselae through broken skin or mucous membranes, usually caused by contact with a
kitten. The primary skin lesion develops within 10 days, and is a small (2 to 5 mm)
erythematous papule. After several weeks, lymphadenopathy develops in a site proximal
to the lesion. Most often, the cervical or axillary nodes are involved. Nodes are single,

large, and tender to palpation. Fever is present in approximately one-third of children.
This condition spontaneously resolves within 1 to 3 months, though treatment with
azithromycin will result in rapid resolution of lymph node swelling. The indirect
immunofluorescent antibody (IFA) assay for detection of serum antibodies to antigens of
Bartonella species is used for diagnosis of catscratch disease.
Another infectious cause of chronic cervical lymph node swelling is nontuberculous
mycobacterium (NTM), also referred to as atypical mycobacterium. NTM is a group of
acid-fast bacteria that are found in environmental sources such as soil and water,
including the biofilm of home aquariums. Cervical lymphadenitis is the most common
manifestation of NTM disease in childhood. Children younger than 5 years are affected.
Lymph node involvement is generally unilateral, in the superficial cervical or
submandibular region, and rarely larger than 3 to 4 cm. The node is nontender, and
enlarges in size slowly over several weeks. Overlying skin may turn a deep purple and
gradually thin, developing a paperlike appearance ( Fig. 47.5 ). Without intervention,
these nodes may suppurate and adhere to overlying skin, resulting in a chronic draining
sinus. Infected children appear well, without systemic symptoms, and may have a history
of being treated unsuccessfully with antibiotics aimed at pathogens of typical bacterial
adenitis (group A Streptococcus or S. aureus ). A clear history of exposure to NTM is the
exception rather than the rule. Formal diagnosis is made by culture. Treatment generally
involves surgical excision of the node, though antimicrobial therapy may play a role for
some patients in addition to or as an alternative to excision.
M. tuberculosis is a rare cause of cervical lymphadenitis in children in the United
States, but remains a significant pathogen in other parts of the world. Children with
tuberculosis may be of any age. Cervical node enlargement occurs with lymphatic
extension from the paratracheal nodes to the cervical and submandibular regions. In
addition, supraclavicular node enlargement can be seen as the result of drainage from the


apical lung pleura and upper lung fields. The most common presentation is an isolated
enlarged node that is nontender; though with progression, the node will become fixed and

matted, adhering to overlying skin. In children with suspected tuberculous lymphadenitis,
it is important to elicit any history of family members or close contacts with a diagnosis
of tuberculosis, symptoms of active disease, or risk factors for acquisition (travel,
homelessness, incarceration, human immunodeficiency virus [HIV] infection). Diagnosis
is made by a combination of skin testing, chest radiograph, and if possible, culture data
from the involved node. In addition, newly available serum interferon-γ–release assays
(QuantiFERON-TB Gold In-Tube test or T-SPOT.TB test) detect interferon-γ generated
by T cells in response to antigens found in M. tuberculosis and are available to aid in
diagnosis. Treatment of cervical lymphadenitis consists of antimycobacterial therapy, and
should follow established recommendations, such as those from the Centers for Disease
Control (CDC) (see Chapter 94 Infectious Disease Emergencies ).


TABLE 47.1
CAUSES OF REGIONAL LYMPHADENOPATHY