The evidence of TB infection or disease outside the CNS can
significantly increase the probability or possibility that a child with
cerebral signs and symptoms can have TBM. However, a great
number of patients, especially when HIV negative, will present
with normal chest radiography or negative tuberculin skin
testing.27 Moreover, particularly in high TB prevalence areas,
a positive skin test with an unrelated illness has been frequently
documented. Taking samples from sites of frequent TB infection
such as lymph nodes, lung and gastric fluid can increase the likelihood
of a positive culture. Gastric aspiration was positive in 68% of
children with TBM.28
In conclusion, considering the need for a rapid diagnosis of TBM,
all possible efforts to demonstrate the probable or possible presence
of this disease must be pursued using all available laboratory
tests and imaging techniques. Moreover, the potential severity of
TBM calls for the immediate treatment of all the doubtful cases.