Methodology of the study Study design:Ambispective cohort study; Observational study;
Diagnostic accuracy study
Sample size: All consecutive patients in the database will be included in the retrospective
study and all new patients registered in the neurology OPD and admitted in the Neurology or
General Medicine or Geriatric medicine or Medical oncology wards will be included in the
prospective arm
Expecting a sensitivity of 70% of sulcal tuberculomas in tubercular meningitis with a range
of 60 to 80, the investigators expect (47030) /1010=84 patients Expecting sulcal
tuberculomas to have a specificity of 80%, with a range of 70 to 90%, the investigators
expect (48020)/1010=64 patients Expecting a 70% prevalence of tubercular meningitis
amongst patients with chronic meningitis, sample size of atleast 120 patients (70% of
120=84).
Subjects:
Study Population: Patients with chronic meningitis as per criteria described
Inclusion criteria
Patients attending Neurology OPD or are admitted in General Medicine or Geriatric
medicine or Medical oncology wards with chronic meningitis diagnosed on the basis
of composite clinical criteria, imaging criteria as well as natural history of the
illness
Atleast 14 years of age of all sexes
Chronic meningitis : Case definition above
Willing to undergo periodic assessment clinically and with MRI as per clinical
condition demands.
Diagnostic criteria for Tuberculous meningitis ▪ Described in the diagnostic test
section ahead
Diagnostic criteria for clinical spinal tubercular arachnoiditis
▪ Developed paraparesis/quadriparesis/sphincter dysfunction due to spinal
radiculomyelitis OR areflexia OR hyperreflexia with no obvious brain parenchymal lesions
(suggestive of spinal meningitis-myelitis) or vision loss due to optico-chiasmatic
arachnoiditis with imaging evidence of arachnoiditis
Sample Size: All consecutive patients presenting with chronic meningitis as described
above will be included
Exclusion criteria for prospective arm
● Not willing to provide consent
Conduct of the study
Study protocol
Consent: Participants or their legally authorized representatives will be explained
about the study and informed written consent will be taken in the language they
understand for the prospective study
Participants will undergo magnetic resonance imaging of the brain and spine with
contrast using the standardized protocol for chronic meningitis used at AIIMS as
the standard of care in the workup of chronic meningitis.
The final diagnosis of Tubercular meningitis will be made based on the criteria
described above and the sensitivity and specificity of sulcal tuberculomas in the
diagnosis of TBM will be determined
Other imaging findings of spinal tubercular arachnoiditis will be collected on a
structured proforma by the radiologist who will be blinded to the clinical
information on the presence or absence of clinical features.
Participants will follow treatment for tuberculosis as per the treating physician's
discretion in terms of anti-tubercular therapy, anti-seizure medication therapy,
duration and dose of corticosteroids and steroid sparing agents.
Data collection and analysis will be done as per protocol Follow up and outcomes
assessed > Participants of the prospective arm will be carefully assessed with
detailed history, clinical examination, necessary laboratory investigations and
imaging > Detailed history and clinical and neurologic examination, lab parameters
and imaging data will be documented into a database as per protocol > Participants
will follow treatment for his/her primary condition as per the treating physician's
discretion > Outcomes will be assessed at 3 months, 6 months and at end of therapy
> The outcome parameters of interest will be modified Rankin scale, visual acuity
at 3 months and end of therapy.
Diagnostic accuracy of imaging parameters in the diagnosis of tubercular meningitis will be
assessed by sensitivity and specificity.
The investigators aim to do a descriptive study of the clinical, laboratory and imaging
parameters of patients tubercular meningitis and spinal tubercular arachnoiditis and compare
with patients with other forms of chronic meningitis.
The treatment strategy, usage of anti-tubercular therapy, usage of corticosteroids, steroid
sparing therapy, and surgical interventions offered will be studied.
Outcomes will be assessed and compared those who have sulcal tuberculumas and those who
don't. The patients with and without spinal arachnoiditis on imaging also will be compared,
and their outcomes assessed. Factors affecting outcomes will be studied and exploratory
analysis will be done. Statistical analysis will be performed on the available information.
Qualitative data will be presented as the number and the percentage of patients in each
treatment group. Quantitative data will be presented as mean and standard deviation, range,
median and inter-quartile range by treatment group. The absence of imbalance between groups
will be checked on baseline variables. Comparisons of qualitative variables between groups
will be performed by a Fisher exact test; comparison of quantitative data will be performed
by a t test or a comparison of median when they will not follow a Normal distribution. All
statistical tests will be performed with the use of a two-sided type I error rate of 5%.