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244 Lymphadenopathy in African Children
Epstein-Barr virus Clinical Presentation
The Epstein-Barr virus causes the acute form of infectious mono- History
nucleosis, presenting with fatigue, malaise, fever, sore throat, hepato-
splenomegaly, and a generalised lymphadenopathy. After the primary Clinical evaluation of a child with enlarged lymph nodes includes
infection, EBV (similar to other herpes viruses) gives rise to lifelong careful history and examination. The following questions should be
latent infection. Because the virus is harboured in the oropharyngeal answered:
cells and B lymphocytes in the blood, it is therefore not surprising that • When did it arise?
both epithelial (e.g., nasopharyngeal Ca) and B lymphocyte activation • Is there any association with infections?
(Burkitt lymphoma) occur. EBV is associated with up to 98% of cases
of endemic Burkitt lymphoma. • How fast is it growing?
Failure to control the EBV infection in immunocompromised patients • Is there any other lymphadenopathy?
may have severe consequences. The decrease in T-cell populations • Are there any systemic symptoms (e.g., night sweats, loss of weight
allows EBV to escape immune surveillance. It may be associated with , bone pain)?
conditions such as X-linked lymphoproliferative syndrome and the T/
NK-cell lymphoproliferative disorders (LPDs) of children and young Physical Examination
adults. These are also sometimes termed severe chronic active EBV Note the following features:
(CAEBV) infections, which have an aggressive clinical course. • position (supraclavicular/posterior triangle neck, etc.);
Kikuchi-Fujimoto disease
• size (significant if >1 cm);
The cause of Kikuchi-Fujimoto disease (histiocytic necrotising lymph-
adenitis) is unknown, although viruses such as herpes and EBV have • consistency (hard/matted/immobile); and
been associated with this condition. This disease appears to represent a • presence of other lymphadenopathy/visceromegaly.
common pattern of response to a variety of aetiological factors rather
than a single clinicopathological entity. Clinical Evaluation
This relatively newly described condition has sparked recent Age of Patient
interest. Although appearing to be largely confined to the Far East,
Age plays a role because lymph nodes are usually not palpable in neo-
where it was described in young women in Southeast Asia, it has also
nates, making neonatal lymphadenopathy suspicious. In our large series
been described in the Americas and other parts of the world. There are
of 1,877 biopsied lymph nodes, the mean age was 7 years (for TB, it
1
no reports of this condition in Africa as yet, although it is being reported
was 5.8 years, and for neoplastic disease, 8.5 years). A comparison
from other developing countries. Reasons for this may be specific to of the ages of all the lymph nodes sampled compared with those with
geography or the overwhelming prevalence of tuberculosis in Africa.
malignancy shows a rather striking difference in those children older
Tropical diseases and lymphadenopathy than 5 years of age, when malignancy appears to increase in prevalence.
• Lymphadenopathy is a feature of acquired toxoplasmosis Size of Significant Lymph Nodes
(Toxoplasma gondii), mainly occurring in cervical nodes. The The size of lymph nodes should be recorded in the initial evaluation
congenital form of the disease does not show lymphadenopathy as and prior to commencing treatment. Although the majority of studies
much as hepatosplenomegaly. avoid giving specific measurements for significant lymph nodes, nodes
• The regional lymphadenopathy that occurs with rickettsial infec- greater than 1 cm were considered abnormal in the cervical region
tions such as tick bite fever is often generalised, but if localised, it (normal being <3 mm). Lymph nodes in the axilla are not considered to
may indicate the site of the bite and assist in diagnosis. Widespread be enlarged unless their diameter exceeds 1 cm for axillary nodes and
trematode infections (e.g., schistsomiasis) may also produce gener- 1.5 cm for inguinal nodes.
alised lymphadenopathy. Pathological lymph nodes are abnormal in size and site for the
particular age of the child but also include those with an irregular or
• Dengue fever is transmitted by the Stegomyia family mosquitoes hard surface as well as lymph nodes that persist for more than 4 to 6
and not infrequently presents with lymphadenopathy in addition to weeks despite adequate antibiotic treatment.
the myalgia, gastrointestinal upset, and rash usually associated with
this condition. Position of Enlarged Lymph Nodes
The main peripheral groups of nodes involved in pathology are the cer-
• Lymphadenopathy may also be present in association with trypano- vical (46%), axillary (23%), inguinal (13%), and submandibular (8%)
somiasis and West African sleeping sickness.
groups of nodes, as well as deeper areas such as the mediastinum and
• Kala azar is associated with lymphadenopathy in certain areas of intraabdominal lymph nodes. The most important area is in the neck,
northern Africa, the Middle East, and South America. It needs to be where cervical lymphadenopathy is the most common initial presenta-
differentiated from tuberculosis and malignancies such as leukae- tion site of the majority of head and neck malignancies and a number
mia and lymphoma. of other pathologies (e.g., lymphoma).
A special risk situation exists with mediastinal nodes that may not
• Lymphadenopathy may also occur with certain zoonotic infections
such as toxocariasis (visceral larva migrans). be clinically obvious but may have exerted pressure on the trachea,
thus compromising the airway. A chest x-ray (CXR) on which the
• Wuchereria bancrofti infection affects the lymphatic system, is dis- mediastinum is broadened in the absence of a thymic shadow is
tributed throughout tropical and subtropical areas of Africa as well suggestive of mediastinal lymphadenopathy. The outline of the trachea
as many other parts of the world, and causes filariasis. Lymphatic and respiratory tree can be traced on CXR, but if suspect, a computed
filariasis can be disabling in the long term, but the problem relates tomography (CT) scan should be performed prior to any anaesthetic
more to lymphangitis than lymphadenopathy per se. Acute infec- procedures being performed (Figure 37.5).
tions are characterised by fever, lymphangitis, headaches, and myal-
gia, mostly in the second decade of life with chronic manifestations
occurring later (>30 years).