Cervical adenitis in children
Common infectious agents
Cervical adenitis is a condition characterized by inflammation of one
or more lymph nodes of the neck. The most common cause of cervical adenitis is
infection. The most common infectious agents are viral.
Though cervical
lymphadenitis can be a manifestation of focal viral infections of the oropharynx
or respiratory tract, often it is part of a more generalized reticuloendothelial.
response to systemic infection.
- Viruses commonly associated with prominent
cervical adenitis include
- Epstein Barr virus (EBV)
- Cytomegalovirus (CMV)
- HIV
- Acute unilateral cervical adenitis is associated in the majority of cases
with
- Staphylococcus aureus
- more
frequent fluctuance and longer duration of symptoms.
- Streptococcus pyogenes
- Neonatal cervical adenitis is generally due to S.
aureus; however, a
cellulitis-adenitis syndrome caused by group B streptococci has been described.
Bacteremia occurs in many of these neonatal patients.
- Anaerobic bacteria may
cause lymphadenitis usually in association with dental caries and periodontal
disease.
- Recurrent cervical adenitis associated with unusual pathogens (Enterobacteriaceae,
fungi, Staphylococcus epidermidis) is often associated with a defect in
granulocyte function.
- Subacute or chronic cervical adenitis, which develops slowly over two or more
weeks is most often caused by cat-scratch disease or mycobacterial infection,
and less frequently due toxoplasmosis.
- Bartonella henslae is the presumptive etiologic agent of cat-scratch disease.
Pathogenesis of cervical lymphadenitis.
-
The lymphatic system of cervical area serves as a line of defense against
infections of the upper respiratory tract, teeth or the soft tissue infections
of the face and scalp.
- Microorganisms that invade these glands are trapped and
destroyed by phagocytic cells.
- The initial histologic response is one of swelling and hyperplasia of sinusoidal lining cells and infiltration of
lymphocytes.
-
The major portals of entry of the microorganisms that spread to the cervical
lymph nodes are upper respiratory tract, mouth, teeth and skin.
Mode of spread
- Staph aureus, anaerobes and atypical mycobacteria are normal inhabitants of
upper respiratory tract.
- Group A Streptococcus, M. tuberculosis and C. diphtheria infection of
cervical lymph nodes result from contact with infected humans by way of airborne
droplets.
- Atypical mycobacteria usually enter through the oral mucosa. Organisms
ingested in infected meat or through unpasteurized milk may enter the
peripharyngeal lymphatics through a break in mucous membranes or secondary to
blood stream.
- EBV and CMV are acquired through contact with infected saliva and other body
fluids.
- Acute infection following trauma or impetigo or other cutaneous lesions
often
is due to S. aureus or Group A Streptococci.
- Chronic infection of regional lymph nodes associated with an
inoculative skin
lesion (lymphocutaneous syndrome) suggest infection due to cat-scratch disease,
tuberculosis, nocardia, tularemia, sporotrichosis or cutaneous mycobacterial
infection.
Clinical characteristics
- Determine the characteristics of lymph nodes
- Localized or diffuse
- Systemic (Lymph nodes, Liver, spleen, marrow) or lymph
nodes only
- Tenderness, Warmth
- Soft, firm, hard
- Matting, adherence to skin, adherence to deeper tissues
- Fluctuation
- Drainage sites
- Mode of onset
- Associated findings
- Duration
- Infectious mononucleosis
- CMV infection
- Suppuration with abscess formation may develop, depending on the
organism and age-related host defenses.
- Conditions that result in significant
suppuration of infected nodes include. S. aureus and GABS infections,
cat-scratch disease, anaerobic infections and mycobacterial disease.
-
Chronic adenitis
- If the adenopathy is of longer duration (subacute or chronic) and the
involved nodes are well localized, non-tender, a granulomatous infection or
malignancy is most likely.
- A history of exposure to TB, insects and animals may
help clarify the most likely etiology.
- If the adenopathy is generalized and
particularly if mediastinal nodes are involved, tuberculosis and histoplasmosis
are more likely.
- If the adenopathy is unilateral, an atypical mycobacterial infection or
cat-scratch disease is more likely.
- Cat-scratch disease
- Cat-scratch disease is sometimes associated
with an indolent granulomatous papule, vesicle or ulcer, however, the primary
lesion may disappear by the time adenitis is seen..
- The inflammation generally
involves a single node or a single group of nodes.
- Suppuration occurs in over
half of the patients.
- Granulomatous inflammation by
palisading epithelioid cells is seen in cat-scratch disease.
- Atypical mycobacterial infection
- Cervical lymphadenitis attributed to atypical mycobacteria is much more
common in the young child than that caused by M. tuberculosis.
- is generally localized to a single tonsillar
or submandibular node.
- In mycobacterial infection the nodes are often
non-tender, the skin overlaying the node may develop a purple color, the
overlying skin may become thinner if untreated.
- Suppuration develops in about
half the cases, followed by skin adhering to the node and spontaneous drainage
resulting in fistula formation.
- Biopsied lymph nodes reveal granulomatous inflammation with caseating
necrosis in mycobacterial and fungal infections.
Diagnosis
-
Establishment of specific cause whenever the infection does not respond to
empiric treatment is important.
- Aspiration of the affected, inflamed node is a
valuable diagnostic test.
- The aspirate should be sent for
- Gram and acid-fast stains
- Aerobic, anaerobic, mycobacterial and fungal cultures.
- Chronic adenitis: The following tests are recommended
- Intradermal skin testing for tuberculosis (5 IU tuberculin).
- Serologic testing for EBV, CMV,
toxoplasmosis, B. henslae, HIV and fungi.
- Chest X-ray.
- Positive PPD skin test may signify tuberculous infection or cross-reactivity
from atypical mycobacterial infection.
- Abnormal chest x-ray is rare in atypical
mycobacterial infection.
- If the diagnosis still remains in doubt and the adenitis is progressing:
Biopsy of the node should be performed.
- Biopsy material should be submitted for the studies outlined above for lymph
node aspirate cultures as well as for routine histology, Giemsa, periodic acid-Schiff
(PAS), and methenamine silver stains.
- Other special stains, for example the
Warthin-Starry silver stain for the CSD bacillus, may be requested when
appropriate.
- If the histology reveals noncaseating granulomas, and the child has a history
of cat exposure, the most likely diagnostic possibility is CSD (cat-scratch
disease).
Treatment of acute, subacute and chronic
bacterial adenitis.
-
Acute suppurative cervical lymphadenitis is most frequently caused by
infection with Staphylococcus aureus or group A Streptococcus.
- Because of the
frequent occurrence of infection due to these two agents, empiric antimicrobial
therapy should be directed against them.
- The incidence of penicillinase-producing
strains of S. aureus is high in most communities, therefore, penicillinase-resistant
penicillins should be used.
- If the patient requires parenteral therapy,
oxacillin or nafcillin may be used, or when oral therapy is deemed to be
adequate, cloxacillin or dicloxacillin is recommended.
- In nodes that progress to
rapid suppuration and abscess formation, S. aureus is the most frequent agent
isolated and drainage is mandatory.
- Tuberculosis
- A 2-month regimen of daily ENH, rifampin, and pyrazinamide followed by a
daily regimen of INH and rifampin for 4 months is currently recommended for
treatment of uncomplicated intrathoracic pulmonary tuberculosis and isolated
cervical lymphadenitis in children.
- Atypical Tuberculosis
- These
microorganisms frequently demonstrate in vitro resistance to commonly employed
anti-tuberculous drugs.
- Surgical excision is the treatment of choice for
non-tuberculous
mycobacterial lymphadenitis.
- Cat-scratch disease is usually a benign, self-limiting disorder requiring no
specific therapy.
- Antimicrobials have no effect on the course of this illness.
(Few patients have been reported to respond to rifampin therapy.)
- If the lymph
node progresses to fluctuance, needle aspiration may hasten resolution and also
relieve the discomfort caused by the enlarged node.