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Lymphadenopathy in African Children 241
Acute Bacterial Lymphadenitis
Aetiology
Unilateral, large, and tender lymph nodes are commonly due to acute
bacterial infection. The most common cause of acute lymphadenitis is a
bacterial infection arising in the oropharynx. Submandibular and upper
cervical nodes are affected in the majority of cases. Axillary, inguinal,
and other locations also may be inflamed. Ultrasonography may detect
an abscess not already apparent on physical examination.
Typical organisms are penicillin-resistant Staphylococcus aureus
and Streptococcus pyogenes. Group B streptoccal adenitis may occur in
the infant with unilateral submandibular swelling, erythema, tenderness,
fever, and irritability. In the older child with dental caries or periodontal
Figure 37.2: Acute suppurative lymphadenitis with abscess. disease, anaerobic germs (e.g., Bacteroides sp., Peptococcus sp.,
Peptostreptococcu) play a role. Following animal (dog) bites or animal
Chronic Lymphadenitis scratches, Pasteurella multocida may cause acute lymphadenitis.
Chronic lymphadenitis may be caused by a reactive hyperplasia virus; Without treatment, the lymph node usually enlarges and becomes
defined infections, such as toxoplasmosis or infectious mononucleo- fluctuant. Thinning over the overlying skin and spontaneous perforation
sis; or chronic granulomas, such as mycobacteria (other than TB), cat may occur. Laboratory findings include an elevation of white blood cell
scratch disease, or possibly TB; or viruses (e.g., Ebstein–Barr, HIV, or and neutrophil count.
cytomegalovirus (CMV)). Treatment
Pathology Initial treatment of acute lymphadenitis consists of administration of a
Lymphadenopathy represents the response to localised or generalised beta-lactamase–resistant antibiotic for 2 weeks, at least 5 days beyond
resolution of acute signs and symptoms. In older children with dental
pathology as a result of antigenic stimulation or infiltration by cellular or periodontal infection, the antibiotic therapy should include an anti-
elements. The larger lymphoid mass as well as a brisk lymphogenic anaerobic antibiotic, such as penicillin V or clindamycin.
response following exposure to new antigens predisposes to lymph If the child appears toxic (high fever, cellulites, respiratory problems)
node enlargement in children. or is quite young, hospitalisation and intravenous (IV) administration
Generalised enlargement of lymph nodes is defined as two or more of antibiotics are often necessary. In these cases, blood cultures should
noncontinuous lymph node regions with enlarged nodes (including be obtained. However, the incidence of bacteremia associated with
intraabdominal lymphadenopathy). It most often occurs as a result pediatric acute adenitis seems to be low.
of systemic disease due to infectious agents, but malignancies, auto- Fluctuance of the lesion is a clear indication for surgical evacuation.
immune disease, and lipid storage diseases, as well as drug reactions Needle aspiration and drainage of the purulent material can be both
and other miscellaneous pathologies, also contribute to the overall diagnostic and therapeutic. It is particularly attractive when treating in
picture. It is often accompanied by other generalised symptoms, such cosmetically important areas. However, repeated aspirations may be
as weight loss, night sweats, and ill health, or symptoms typical of the necessary, and judicious antibiotic therapy is required.
underlying pathological condition. The aspirated material should be cultured for aerobic and anaerobic germs
In contrast, localised lymphadenopathy occurs mainly as a result as well as for mycobacteria. In addition, it is helpful to examine the material
of diseases or infections in the node or their drainage areas. It can be by Gram and Ziehl–Neelsen acid-fast stain. In the immunocompromised
cervical, axillary, inguinal, or other (e.g., supratrochlear, occipital, etc.).
child, fungal infections have to be taken into account.
Reactive Hyperplasia An alternative to node aspiration is open drainage under general
The majority of enlarged lymph nodes in children occur as a result anaesthesia, which is safe and highly successful. The node can be
of infective agents; viral infections show only reactive hyperplasia incised and packed loosely with a Penrose drain or a gauze strip. An
in the majority (in as many as 48% of patients) without a specific attempt should be made to open and drain all loculations. The drain can
cause being identified. This is not entirely unexpected considering usually be removed after a period of several days.
the empiric use of antibiotics, which may mask certain aetiological Complications
agents, and the difficulty of identifying causative pathogens, par-
Major and life-threatening complications reported in children with sup-
ticularly in Africa. This high prevalence of reactive hyperplasia does
purative cervical lymphadenitis are fasciitis, carotid artery aneurysm,
not exclude the need for careful clinicopathological correlation to
and rupture, thrombosis of the jugular vein, generalised septic emboli-
improve diagnostic capability, however.
sation, mediastinal abscess, and purulent pericarditis.
The most probable aetiology guides the diagnosis of lymphadenopathy.
Despite the myriad causes, lymph nodes enlarge as a result of proliferation Mycobacterial-Related Lymphadenitis
of normal lymphoid elements or infiltration by phagocytic cells or Tuberculosis and Lymphadenopathy
malignant cell deposits. Many are caused by viral infections, which result
Although the incidence of TB has stabilised or declined in most world
in small, self-limiting lymph nodes. If a bacterial aetiology is anticipated,
regions, it is increasing in Africa, Southeast Asia, and the eastern
an empiric course of antibiotics that cover streptococci and staphylococci
Mediterranean countries, being fuelled by the HIV pandemic with
is appropriate, with re-evaluation. Abscess formation is treated surgically.
which it is closely associated. Tuberculous lymphadenitis and malig-
Chronic Granulomas nant nodal spread remain the most frequently encountered reasons for
1
In our series of 1,877 surgically biopsied lymph nodes, 484 (36.3%) lymph node enlargement. Tuberculosis (TB) is the most frequent form
had chronic granulomatous changes. Although M. tuberculosis was the of extrapulmonary tuberculosis and is identified in at least 28% of most
causative agent in the majority, in almost 10% the causes of the chronic series of cervical lymphadenopathy. Given the historical difficulties in
granulomas were not always clear but included sinus histiocytosis with diagnosis, the actual figure for Africa is probably somewhat higher.
massive lymphadenopathy (Rosai–Dorfman disease), syphilis, yaws,
and toxoplasmosis.