Tuberculosis Meninegea

Pasco BMC Research Notes 2012, 5:49
http://www.biomedcentral.com/1756-0500/5/49

RESEARCH ARTICLE

Open Access

Diagnostic features of tuberculous meningitis: a
cross-sectional study
Paul Matthew Pasco

Abstract
Background: Tuberculous meningitis (TBM) is a common central nervous system infection in the Philippines;
however it is difficult to diagnose as findings are non-specific.Hence we decided to determine if, among patients
with chronic meningitis syndrome, the following are associated with the diagnosis: new-onset seizures; focal
neurologic deficit; pulmonary tuberculosis (PTB) on chest X-ray; cerebrospinal fluid (CSF) pleocytosis with
lymphocytic predominance; decreased CSF glucose; increased CSF protein.
Methods: Adult patients with suspected TBM were enrolledafter informed consent was obtained. Baseline physical
examination and diagnostic tests including CT scan of the head with contrast and CSF analysis for acid fast bacilli
(AFB) smear, TB culture and cryptococcal antigen detection were done and results collected. Definite TBM was
defined as positive AFB smear or positive TB culture or positive basal meningeal enhancement on CT contrast
study.Logistic regression was done to determine which were associated with a diagnosis of TBM.
Results: 91 patients were included. Using the gold standard criteria mentioned above, 44 had definite TBM; but if
subsequent clinical course and response to anti-Koch’s therapy are considered, 68 had a final diagnosis of TBM.
After logistic regression was performed, only abnormal CSF (the combination of CSFpleocytosis with lymphocytic
predominance, decreased CSF glucose, and increased CSF protein) was associated with the diagnosis of TBM.
Conclusion: In patients with chronic meningitis syndrome, only abnormal CSF was associated with the diagnosis
of TBM.

Background
Tuberculous meningitis (TBM) is the most dreaded
manifestation of tuberculosis, and is a common infection
of the central nervoussystem (CNS) especially in developing countries like the Philippines where tuberculosis
is highly endemic. The incidence follows that of pulmonary tuberculosis, and is associated with high mortality and morbidity [1]. In a large-scale epidemiological
study of extrapulmonary tuberculosis in the United
States, CNS involvement was noted in 5-10% of extrapulmonary tuberculosis cases, with morerecent CDC
data in 2005 indicating that 6.3% of extrapulmonary
cases (1·3% of total tuberculosis cases) involve the CNS
[2].
Tuberculosis in the Philippines ranks sixth among the
top causes of morbidity and mortality, with rates of
134·1/100,000 and 31·2/100,000 respectively in 2005. As
Correspondence: pmdpasco@post.upm.edu.ph
Dept of Neurosciences, UP-PGH Medical Center, Taft Ave, Manila,Philippines

for TB of the CNS, based on partial prevalence data
from eight Metro Manila hospitals, TBM is the most
common primary CNS infection in adults in the country, accounting for 28·9% of all cases of primary CNS
infections [3]. In the Philippine General Hospital the
case fatality rate for CNS infections is 20%, and prognosis depends on how soon a diagnosis is made and
appropriatetherapy is started.
The diagnosis of TBM remains to be difficult. As with
other forms of TB the gold standard is isolation of the
organism through culture or detection of its presence by
acid-fast staining. However the yield from acid-fast
staining and culture remains to be very low, probably
because of the low concentration of bacilli in the cerebrospinal fluid (CSF). The author ’ s own series of63
cases had a positive culture yield in only 3 of these [4].
Molecular methods, such as polymerase chain reaction
(PCR)-based diagnostic techniques, have begun to be
applied in the local setting, but are relatively expensive,
and the yield greatly depends on stringent quality

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