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246 Lymphadenopathy in African Children

on the clinical findings, response to antibiotic therapy, and Mantoux
and CXR results. Tuberculosis should be excluded by the Mantoux skin
test and chest x-ray in addition to gastric washings and cultures.
The majority of cases of lymphadenopathy are related to infection,
so it is logical to rule out acute infection as a possible cause. Many
clinicians would thus advocate the use of empiric antibiotics in the
initial stages in the absence of other worrying signs. A 7–10 day trial of
antibiotics is therefore advocated.
Biopsy and Sampling
Fine needle aspiration biopsy (FNAB) and sampling are indicated by Figure 37.8: Surgical biopsy of cervical lymph node (lymphoma).
any of the following conditions of the lymph nodes:
• no response to antibiotic therapy in 4–6 weeks (>2 cm);
• rapid increase in size;
• hard, matted lymph nodes in the posterior triangle or the supracla- Do not fix
Microbiology
vicular region of the neck; and Microbiology Do not fix
Cts
Cts Simeunovic E,
Make imprints
• difficulty in diagnosis. Make imprints
Arnold M, Sidler D, Moore
Malignancy in lymph nodes may be difficult to assess, particularly SW
in the early stages when they appear as small blue round cells. There is F/S
F/S
E
Histolog
a real risk of malignancy. Specialised tests such as immunostaining and EM M Histology y
Surface
flow cytometry remain useful adjuncts where available. Surface
marke
Fine Needle Aspiration marker r
Although excision biopsy remains the gold standard in diagnosis, FNA Figure 37.9: Schematic outline for handling lymph node biopsy specimens.
has changed the practice in adult surgery in the modern era and may
provide material to establish an early diagnosis in children.
Technically, FNA makes several passes with a 22-gauge needle from
a variety of angles, using suction in the syringe once the capsule of the
gland is entered on each occasion before the needle is withdrawn. A small
amount of saline may be aspirated, and the obtained cells are expressed
onto a glass slide and fixed in the same way as for a Papanicolau test
(Pap smear). It is then submitted to the laboratory for analysis.
FNA is a means of a rapid and definitive diagnosis of tuberculosis
in the majority of cases of suspected tuberculous lymphadenitis. Expert
care should therefore be expressed in interpreting negative FNA results
to exclude a false sense of security. It must be stressed, however, that the
interpretation of a FNA in a child is a highly specialized area of expertise,
and in most cases cannot be completely sufficient to make the diagnosis
of lymphoma. Its major value is probably in establishing metastatic
spread from a known tumour and providing material for culture.
The definitive diagnosis is then based on cytomorphology and
identification of the organism. FNA is, however, difficult to perform
without sedation in the younger child and should be regarded as a
diagnostic triage tool, being accurate only as far as its positive findings
are concerned. It yields a smaller sample and gives no information on
lymph node architecture so it must lead to a more difficult diagnosis in
the absence of flow cytometry.
In a recent study, cultures for the TB organism were positive in
5
79/175 patients (45%) of those subjected to FNA. In these, 61 (77%)
were identified as Mycobacterium tuberculosis with M. bovis (bacille
Calmette-Guérin) being identified in the remainder. Where Burkitt
lymphoma is a possibility, flow cytometry techniques identify the
abundance of B lymphocytes in the specimen.
Surgical Lymph Node Biopsy
Lymph node biopsy remains an important and valuable surgical diag-
nostic tool in the evaluation of lymphadenopathy with very minimal
risk to the patient (Figure 37.8). It allows the assessment of gland archi-
tecture in addition to the cytological features, thereby allowing for early
diagnosis. It should be the endpoint of all cases of lymphadenopathy
where a diagnosis is not readily forthcoming.

Figure 37.10: Surgical technique to excise lymph nodes.