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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