Diagnostic criteria for tuberculous meningitis and their validation

The Role of Diffusion Tensor Imaging in CNS Tuberculosis

Background and objective Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains a significant global health concern, with India being a hotspot for the disease burden. Central nervous system (CNS) tuberculosis, though comprising a smaller proportion of total TB cases, is associated with significant morbidity and mortality. This study aimed to explore the utility of diffusion tensor imaging (DTI) in assessing the microstructural changes in white matter tracts associated with CNS tuberculosis. Materials and methods This study was conducted over two years at the All India Institute of Medical Sciences, Rishikesh. We employed a cross-sectional observational design and included patients with definite or highly probable tuberculous meningitis, alongside healthy controls. Results Our findings revealed a significant reduction in fractional anisotropy (FA) values in various white matter tracts of patients with CNS tuberculosis compared to healthy individuals. This reduction in FA correlated with the severity of tuberculous meningitis, particularly in the corpus callosum. Additionally, DTI highlighted distinct patterns of white matter involvement around intraparenchymal lesions, suggesting potential implications for clinical outcomes. The study emphasizes the utility of FA values in grading disease severity and prognosticating treatment outcomes in CNS tuberculosis. Conclusions Overall, this study provides valuable insights into the microstructural alterations in white matter tracts associated with CNS tuberculosis, highlighting the potential of DTI in early diagnosis, grading disease severity, and monitoring treatment response. We believe these findings will pave the way for further research to optimize the clinical management of this debilitating disease.

Escalate: Linezolid as an add on treatment in the intensive phase of tubercular meningitis. A randomized controlled pilot trial

Most drugs used in the treatment of Tuberculous Meningitis have limited CNS penetration thereby limiting efficacy. CSF penetration of linezolid is 80-100%.The study was a prospective, randomized, open label with blinded outcome assessment pilot trial carried out in patients with TBM. Patients were randomized in a 1:1 ratio into two treatment groups either to receive standard ATT alone or add on oral 600 mg BD Linezolid for 4 weeks along with standard four drug ATT [HRZE/S]. Primary outcome was safety and mortality at the end of one and three months measured by intention to treat analysis. 29 patients were recruited and 27 completed three months of follow up. There was no significant difference in terms of mortality with Odds ratio (95% CI) of 2 (0.161-24.87; p = 1) at one month and 0.385 (0.058-2.538; p = 0.39) at three months. There was a significant improvement in GCS in Linezolid group at one month and mRS within the Linezolid group at one and three months. No major safety concerns were observed. The sample size is underpowered to draw any definitive conclusions but improvement in mRS and GCS as well as mortality change make a case for a large sample size trial.

Cyclophosphamide therapy as an adjunct in refractory post-tubercular arachnoiditis

INTRODUCTION

There is no satisfactory treatment for post tubercular arachnoiditis (TB arachnoiditis). We did this study to investigate the efficacy and safety of cyclophosphamide as adjuvant therapy for post TB arachnoiditis refractory to corticosteroids and anti-tubercular therapy (ATT).

METHODS

This was a retrospective case series of patients of refractory post TB arachnoiditis leading to paraparesis and vision loss who received cyclophosphamide as an adjuvant therapy along with standard ATT and corticosteroids. These patients were treated with intravenous cyclophosphamide (dose 500 mg/m²) once a month for 4 consecutive months after informed written consent and were assessed clinically and radiologically before and after cyclophosphamide therapy.

RESULTS

We had 4 patients with refractory post TB arachnoiditis of whom three became independently ambulatory. There was significant clinical as well as radiological improvement in all the patients.

CONCLUSIONS

Cyclophosphamide therapy could be an effective therapy for patients with refractory post TB arachnoiditis. Well-designed randomized controlled studies are essential to study the safety and efficacy of cyclophosphamide in this condition.

A Case of Brain Tuberculosis With an Unusual Presentation Mimicking Viral Fever During a Dengue Outbreak in Bangladesh

Both dengue and tuberculosis are endemic in South Asian countries, including Bangladesh. Here we report an interesting case presenting as suspected dengue fever and eventually diagnosed as a case of brain tuberculosis. A 27-year-old immunocompetent male presented to us with fever, headache, retro-orbital pain, and photophobia for five days. He had no other complaints, and clinical examination findings were normal. Full blood count revealed neutrophilic leukocytosis; dengue antigen test and anti-dengue antibody test were negative. Magnetic resonance imaging (MRI) of the brain showed both supra and infra-tentorial multiple small (2-4 mm) gadolinium-enhancing lesions suggestive of tuberculomas. A cerebrospinal fluid study revealed lymphocytic pleocytosis with raised protein, low sugar level, and positive Gene Xpert MTB/RIF (Cepheid, California, US) assay test. Investigations did not reveal the involvement of other organs except for the brain. We started standard anti-tuberculosis therapy (HRZE) along with steroids and pyridoxine, and the patient became symptom-free within one week. The patient was discharged with the advice of follow-up after one month. The clinical course and all investigation findings of this case are presented. Central nervous system tuberculosis may present with non-specific signs and symptoms and may be misdiagnosed as other infections, including dengue, particularly during an ongoing epidemic. It may cause significant morbidity and mortality when the diagnosis is delayed due to its vague clinical presentation.

Comparison of disease profiles and three-month outcomes of patients with neurological disorders with and without COVID-19: An ambispective cohort study

Objective:

Methods:

Results:

Conclusion:

Predictors of Infarction in Tuberculous Meningitis in Indian Patients

BACKGROUND

Stroke is a devastating complication of tuberculous meningitis (TBM) and is an important determinant of its outcome. We propose a model which would help to predict development of infarction or cerebrovascular events in patients of TBM.

METHODS

A prospective study with n=129 patients of TBM were evaluated for predictors and outcomes of stroke. A diagnostic grid was formulated with clinical, laboratory and radiology as parameters to predict the vascular outcomes. All patients were followed up for mortality and disability on the basis of modified rankin score (mRS). MRI & CSF cytokines TNF-alpha, IFN- gamma & IL-6,8, 10 were measured at baseline and 3 months. The diagnosis of TBM included definite, probable & possible types and stage I & II with early and late onset of symptoms respectively.

RESULTS

The mortality was 16.2% and 19.4% of all patients developed stroke. The mean GCS, barthel index and mRS at admission was 57.03± 9.5,10.2±2.3 & 3.3±0.03 respectively mild to moderate infection and functional limitation. Barthel index (BI) happened to be a strong predictor [F=32.6, p=0.001, t=15.5, βeta coefficient =0.002] followed by biomarker TNF-α [F=18.9, p=0.02, t= -2.07, βeta coefficient=-0.04]. N=25 patients developed stroke with TNF-α, IL-6, IFN -γ showing statistically significant increase in all the stroke affected TBM (95% CI; 4.5 to 1.2; p=0.003). At 3 months, it was observed that mRS was statistically significant between stage I & II (95% CI; 5.4 to 2.1; p=0.04).

CONCLUSIONS

Our data revealed that 19.4% patients developed vascular events during the hospital stay or follow up. We recruited late onset TBM as compared to early onset. BI, TNF-α, IL6 are most potent predictors of stroke post TBM.

Assessment of Blood-Brain Barrier Integrity in Tuberculous Meningitis Using Dynamic Contrast-Enhanced MR Perfusion

Objective Tuberculous meningitis (TBM) is the most common form of central nervous system tuberculosis. The aim of the study was to quantitatively evaluate blood-brain barrier (BBB) perfusion changes in TBM patients using dynamic contrast-enhanced (DCE) MR perfusion. Methods and Material Thirty untreated patients of TBM and 10 healthy controls were prospectively evaluated by conventional imaging and DCE MR perfusion. Mean permeability indices- K trans and Ve-were calculated from multiple regions of interest (ROIs) placed in basal cisterns and comparison was done between the patients and controls. Results The permeability indices were significantly higher (where p < 0.001) in cisterns of TBM patients who showed basal meningeal enhancement when compared with healthy controls. Significant differences in permeability were observed between "enhancing" cases and controls as well as in "enhancing" cases when compared with the "non-enhancing" cases. However, no significant difference was observed in the mean cisternal value between "non-enhancing" cases and the controls. K trans with a cutoff value of > 0.0838 had 81.6% sensitivity and 78.6% specificity in differentiating cases and controls while V e mean value with a cutoff value of 0.0703 showed 86.8% sensitivity and 91.4% specificity in predicting the permeability difference between the cases and controls. Conclusion DCE MR perfusion is useful in the quantitative measurement of disruption of BBB and perfusion alterations in patients of TBM.

MR vessel wall imaging in tubercular meningitis

PURPOSE

Tubercular meningitis (TBM) has the propensity to cause secondary vasculitis through various mechanisms leading to development of cerebrovascular complications. These vascular involvements can be detected by vessel wall imaging (VWI). In this study, we aimed to study detailed findings of vessel wall imaging in cases of tubercular meningitis.

METHODS

All consecutive patients of suspected tubercular meningitis in whom diagnosis of TBM could be made according to diagnostic criteria given by Ahuja et al. were included in the study. High-resolution MR VWI and time of flight (TOF) magnetic resonance angiography (MRA) were done along with routine MRI sequences. Arteries up to second-order branches were studied, and statistical analyses were done with respect to stage of tubercular meningitis, infarctions and TOF MRA findings.

RESULTS

Out of all 101 cases of TBM, infarctions were found in 49 cases (48.5%), and vessel wall enhancement was seen in 67 cases (66.3%). With increasing severity of disease, more severe vascular involvement was seen on VWI. There was significant association between enhancement of individual arteries and infarctions in their territories. VWI had better sensitivity than the MRA, while MRA had better specificity than VWI for detection of vascular complications.

CONCLUSION

Tubercular vasculitis can be detected by VWI in the form of nodular or smooth segmental enhancement of vessel wall with or without stenosis. Incorporation of VWI in routine MR imaging can play a greater role in early detection and management of cerebrovascular complications which can help to improve prognosis of the disease.

Clinical Spectrum of Central Nervous System Tuberculosis and the Efficacy of Revised National Tuberculosis Control Program in its Management

Introduction

Tuberculosis (TB) is a major global problem and poses a threat which is of considerable magnitude, with an estimated one-third of the population infected with TB bacillus.

Aim

The aim of this study is to study the treatment outcomes in patients with various forms of neurological TB treated with the standardized Revised National TB Control Program (RNTCP), directly observed treatment short-course (DOTS).

Materials and Methods

Patients diagnosed to have TBM, tuberculoma with or without spinal arachnoiditis (central nervous system tuberculosis-TB [CNS-TB]) were categorized as per the RNTCP guidelines and received DOTS Category I or Category II thrice-weekly intermittent treatment as deemed appropriate.

Results

The outcome of management with the standard RNTCP DOTS regimen was that a success rate (treatment completed) of 75%, the default rate of 6.6%, and a mortality of 3.3%. The target fixed by the RNTCP is to achieve a cure rate of 85%. We were able to document successful completion of treatment in 75% which is close to the target fixed by RNTCP. The default rate is 6.6% which quite negligible when compared to the unsupervised therapy which has a default rate of 50%.

Conclusion

The most important factor in predicting the outcome of treatment in CNS-TB is early diagnosis and the timing of initiation of antituberculous treatment. Early initiation of treatment is associated with better treatment outcomes.

Inadequate diagnostics: the case to move beyond the bacilli for detection of meningitis due to Mycobacterium tuberculosis

Tuberculosis (TB) meningitis is extremely difficult to diagnose due to its pauci-bacillary disease nature and new techniques are needed. Improved test sensitivity would allow for greater clinician confidence in diagnostic testing and has the potential to improve patient outcomes. Traditional microbiologic and molecular tests for TB meningitis focus on detection of TB bacilli and are inadequate. Smear microscopy is rapid but only ~10-15  % sensitive. Culture has 50-60  % sensitivity but is slow. Xpert MTB/Rif Ultra is a rapid, automated PCR-based assay with ~70  % sensitivity versus clinical case definition. Thus, even the best current testing may miss up to 30  % of cases. Clinicians are often left to treat empirically with prolonged regimens with significant side effects or risk a missed case that would result in death. Rather than relying strictly on microbiologic or molecular testing to diagnose TB meningitis, we propose that testing of CSF for biomarkers of host response may have an adjunctive role to play in improving the diagnosis of TB meningitis.

Practice Trends in Treating Central Nervous System Tuberculosis and Outcomes at a Tertiary Care Hospital: A Cohort Study of 244 Cases

Introduction

Tubercular meningitis (TBM) is a common cause of chronic meningitis in India; however, there is a paucity of literature on optimum duration and choice of drug therapy.

Materials and Methods

This was an ambispective cohort study.

Results

Two hundred and forty-four patients of central nervous system tuberculosis (CNS TB) who were seronegative for HIV were studied of whom 198 had TBM and 46 patients had tuberculoma without meningitis. Before completion of treatment, 84% of TBM patients underwent imaging. There was no difference in disability or mortality in patients, who were treated with various drug regimens in terms of duration of therapy or number of drugs at initiation of treatment. However when patients developed new complications, adding more drugs improved survival. Prolonging corticosteroid administration in patients with nonsatisfactory improvement at 8 weeks was not associated with prevention of disability.

Conclusions

CNS TB is treated by neurologists and physicians in India, as per their experience due to different recommendations in various guidelines. There is a tendency to decide when to stop treatment based on neuroimaging given the fear of poor outcomes associated with recurrence of the disease. The duration of treatment or choice of drugs at the start of treatment did not affect disability.

Hypothalamic and pituitary dysfunction is common in tubercular meningitis: A prospective study from a tertiary care center in Northern India

INTRODUCTION

Current literature is poor with respect to well conducted prospective studies of hypothalamic pituitary axis (HPA) dysfunction in tubercular meningitis (TBM). As hormonal deficiencies are associated with poor clinical outcome in various neurological and non-neurological disorders, we prospectively evaluated the hypothalamic pituitary axis (HPA) dysfunction in TBM.

PATIENTS AND METHODS

Present study included newly diagnosed drug naive TBM patients (n = 63) at a tertiary care centre in Northern India. All patients underwent detailed clinical, radiological evaluation (Gadolinium enhanced magnetic resonance imaging of brain) and HPA hormonal profiles (electrochemiluminescence assay) both at initial presentation and at six month follow up. All the data was recorded on a predesigned proforma.

RESULTS

77.8% patients had definite and 22.2% had highly probable TBM. 84.2% of patients had pituitary hormonal abnormalities at presentation. These included hyperprolactinemia (49.2%), secondary adrenal deficiency (42.9%), secondary hypogonadism (38.1%) and central hypothyroidism (9.5%). At follow up, 42.1% patients had HPA abnormalities [hyperprolactinemia (13.2%), secondary hypogonadism (15.8%), secondary adrenal deficiency (10.5%) and central hypothyroidism (10.5%)]. On multivariate logistic regression analysis, secondary hypocortisolism (Odd ratio: 4.042; 95% CI = 1.074-15.22; P = .039) was associated with poor outcome in TBM.

CONCLUSION

Abnormalities of HPA are common in TBM. Patients with TBM should be evaluated for dysfunction of HPA and treated accordingly.

Clinical and radiological predictors of outcome in tubercular meningitis: A prospective study of 209 patients

OBJECTIVES

The predictors of poor outcome in tuberculous meningitis (TBM) remain to be delineated. We determined role of various clinical, radiological and cerebrospinal fluid (CSF) parameters in prediction of outcome in TBM.

PATIENTS AND METHODS

Current study was a prospective observational study including 209 patients of TBM. All patients underwent detailed evaluation including Gadolinium enhanced Magnetic resonance imaging (GdMRI) of brain as well as tests to detect evidence of tuberculosis elsewhere in body. They also underwent GdMRI at three and nine month follow up. All patients received treatment as per standard guidelines.

RESULTS

Mean age was 30.4±13.8years. 139 (66.5%) patients had definite TBM while 70 (34.5%) had highly probable TBM. 53 (25.4%) patients died. On univariate analysis, longer duration of illness, altered sensorium, stage III TBM, hydrocephalus and exudates correlated with poor outcome. On multivariate analysis presence of hydrocephalus (p=0.003; OR=3.2; 95% CI=1.5-6.7) and stage III TBM (p<0.0001; OR=8.7; 95% CI=3.7-20.2) correlated with higher risk of mortality. In addition, there was significant positive association between presence of hydrocephalus (p=0.05; OR=2.2; 95% CI=0.97-5.1), stage III TBM (p<0.0001; OR=28; 95% CI=4.9-158) and presence of altered sensorium (p=0.05; OR=22; 95% CI=0.99-4.8) with either death or survival with severe disability.

CONCLUSIONS

It is possible to prognosticate TBM using a combination of clinical and radiological. The duration of illness (65.9±92days) before diagnosis of TBM continues to be unacceptably long and this stresses on need to educate primary care physicians about TBM. Future studies where intensity and duration of treatment is guided by these cues may help in sorting out some of the most difficult questions in TBM, namely duration of antitubercular therapy as well as dose and duration of steroid therapy etc.

Cytokines do play a role in pathogenesis of tuberculous meningitis: A prospective study from a tertiary care center in India

BACKGROUND

Though animal studies have suggested a role for proinflammatory cytokines in pathogenesis their exact role in pathogenesis of human meningeal tuberculosis continues to be controversial with different studies yielding contradictory results.

AIM AND OBJECTIVES

To study the levels of proinflammatory cytokines in serum and cerebrospinal fluid (CSF) of patients with tubercular meningitis (TBM) and to determine whether these correlate with disease severity.

PATIENTS AND METHODS

Present study included 146 patients with TBM (90- Definite TBM; 56- Probable TBM), diagnosed according to criteria laid by Ahuja et al. which were modified to include CSF nucleic acid based tests. Serum (n=146) and CSF (n=140) levels of various proinflammatory cytokines (IL-1β, IL-2, IL-6, TNF-α and IFNγ) were compared between TBM patients and healthy volunteers (n=99). These levels were correlated with various clinical, radiological and CSF parameters of TBM patients.

RESULTS

Proinflammatory cytokines include cytokines which promote systemic inflammation. In current study, the serum and CSF levels of various cytokines (IL-2, IL-4, IL-6, IL-1β, IFN-γ and TNF-α) were significantly elevated in TBM patients compared to controls. A significant correlation was found between a) Higher stage of TBM and various cytokines (except for serum IL-6 and CSF IFN-γ); b) High CSF TNF-α, IL-4 and IL-1β with severity of hydrocephalus; c) High CSF IL1β and IFN-γ with presence of exudates on MRI; d) Serum and CSF levels of all cytokines with poor outcome as determined by death or as defined by S and E ADL (Schwab and England activities of daily living) score or by GOS (Glasgow outcome scale) (except for interferon gamma); and e) Serum and CSF IL-4 and IL1β with presence of infarcts on MRI brain.

CONCLUSION

Proinflammatory cytokines play an important role in the pathogenesis of TBM and contribute significantly towards severity of disease.

Proton NMR metabolic profiling of CSF reveals distinct differentiation of meningitis from negative controls

BACKGROUND

Cerebrospinal fluid (CSF) is an essential bio-fluid of the central nervous system (CNS), playing a vital role in the protection of CNS and performing neuronal function regulation. The chemical composition of CSF varies during onset of meningitis, neurodegenerative disorders (positive controls) and in traumatic cases (negative controls).

METHODS

The study design was broadly categorized into meningitis cases, negative controls and positive controls. Further differentiation among the three groups was carried out using Principal Component Analysis (PCA) followed by supervised Partial Least Square Discriminant Analysis (PLS-DA).

RESULTS

The statistical analysis of meningitis vs. negative controls using PLS-DA model resulted in R² of 0.97 and Q² of 0.85. There was elevation in the levels of ketone bodies, total free amino acids, glutamine, creatine, citrate and choline containing compounds (choline and GPC) in meningitis cases. Similarly, meningitis vs. positive controls resulted in R² of 0.80 and Q² of 0.60 and showed elevation in the levels of total free amino acids, glutamine, creatine/creatinine and citrate in the meningitis group. Four cases of HIV were identified by PLS-DA model as well as by clinical investigations.

CONCLUSION

On the basis of metabolic profile it was found that negative control CSF samples are more appropriate for differentiation of meningitis than positive control CSF samples.

HMGB1 level in cerebrospinal fluid as a complimentary biomarker for the diagnosis of tuberculous meningitis

Purpose

High mobility group box-1 (HMGB1) is a proinflammatory, DAMP protein that participates in many pathological conditions. In this study, we evaluated the usability of CSF HMGB1 as a biomarker for the diagnosis of tuberculous meningitis (TBM).

Methods

A total of 59 TBM patients and 169 control patients were included in our study. CSF samples were obtained and analyzed for HMGB1 using a commercial ELISA kit.

Results

The mean CSF HMGB1 was 19.36 ng/ml in TBM patients (n = 59) versus 3.12 ng/ml in non-TB meningitis patients (n = 30), 2.13 ng/ml in patients with extra neural tuberculosis (n = 73), and 1.06 ng/m in controls (n = 66). According to the receiver operator characteristic curves, a cut-off value of 3.4 ng/ml was calculated, indicating that the sensitivity and specificity of CSF HMGB1 alone in diagnosis of TBM were 61.02 and 89.94 %, respectively. In patients with extra neural tuberculosis and a high risk of TBM, CSF HMGB1 seemed to be a good candidate for early differential diagnosis of TBM at the cut-off value of 3.8 ng/ml, when the sensitivity and specificity were 79.49 and 94.52 % respectively.

Conclusion

Our finding may prove to be clinically useful, because CSF HMGB1 ELISA can be performed in almost all clinical laboratories, especially when sophisticated technologies are either time consuming or unavailable.

Tuberculous meningitis in an immunocompetent male complicated by hydrocephalus

A 39-year-old man, born in India but resident in the UK for 10 years, was travelling in America when he became feverish with an altered mentation. He reported a 10-day history of fever, photophobia, headache and fatigue. His medical history included hypothyroidism and migraine. He was a non-smoker, did not consume alcohol and denied a history of drug use. He was transferred to the emergency department. Laboratory investigations confirmed hyponatraemia (sodium 128 mmol/L). A chest radiograph confirmed no focal consolidation. Further investigation with a CT brain was unremarkable. A lumbar puncture was suggestive of viral meningitis, with a raised white cell count, lymphocytosis, high protein and low glucose. His PCR was negative for enterovirus and herpes simplex virus. Further investigation with a CT thorax, abdomen and pelvis demonstrated bilateral upper-lobe infiltrations. A bronchoalveolar lavage was negative for acid alcohol fast bacilli (AAFB). A diagnosis of tuberculous meningitis was rendered following a repeat lumbar puncture. Gram stain revealed AAFB and PCR was also positive. He started antitubercular treatment and corticosteroids. A repeat CT brain demonstrated ventriculomegaly, suggestive of hydrocephalus and an MRI head revealed likely communicating hydrocephalus with basilar enhancement. He was repatriated to the UK. Eleven days post transfer, he became acutely confused and required external ventricular drain insertion. After surgical management of his hydrocephalus, there was no further neurological deterioration. He remains committed to his neurorehabilitation.

Visual pathway abnormalities in tuberculous meningitis

Ophthalmological complications are common and disabling in patients with tuberculous meningitis. We aimed to study the visual pathway abnormalities in patients with tuberculous meningitis. Forty-three patients with tuberculous meningitis were subjected to visual evoked responses (VER) and neuroophthalmologic assessment. Neuroophthalmologic assessment revealed abnormalities in 22 (51.3%) patients. VER were found to be abnormal in 27 (62.8%) patients. The VER abnormalities included prolonged P100 latencies with relatively normal amplitude and significant interocular latency differences. Visual pathways abnormalities are common in patients with tuberculous meningitis and are often subclinical. Pathophysiologic explanations for electrophysiological abnormalities on VER in these patients are incompletely understood and needs further exploration.

Validation of Thwaites Index for diagnosing tuberculous meningitis in a Colombian population

OBJECTIVE

To determine the diagnostic accuracy of Thwaites Index (TI) in a Colombian population to distinguish meningeal tuberculosis (MTB) from bacterial meningitis (BM) and from non-tuberculous meningitis. Exploratory analyses were conducted to assess the TI's validity for patients with human immunodeficiency virus (HIV) and children above six-years-old.

METHODS

The study included 527 patients, the TI was calculated and results compared with those of a reference standard established by expert neurologists. Sensitivity, specificity, area under the curve of receiver-operator characteristics (AUC-ROC) and likelihood ratios were calculated.

RESULTS

The AUC-ROC to distinguish MTB from non-tuberculous meningitis was 0.72 (95% CI: 0.67-0.77) for HIV negative adults. AUC-ROC was 0.62 (95% CI: 0.50-0.74) for HIV positive adults and 0.83 (95% CI: 0.68-0.97) for children. For distinguishing MTB from BM the AUC-ROC was 0.78 (95% CI: 0.73-0.83); furthermore, the AUC-ROC was 0.57 (95% CI: 0.31-0.83) for HIV positive adults and 0.86 (95% CI: 0.73-0.99) for children.

CONCLUSION

The TI was sensitive but not specific when used to distinguish MTB from BM in HIV negative adults. In HIV positive adults the index had low diagnostic accuracy. Moreover, the TI showed discrimination capability for children over 6years; however, research with larger samples is required in these.

Identification of Mycobacterium tuberculosis in the cerebrospinal fluid of patients with meningitis using nested PCR

Tuberculous meningitis (TBM) is the most severe form of tuberculosis. It is caused by Mycobacterium tuberculosis (M. tuberculosis; MT) and it is very difficult to diagnose. The symptoms are similar to other infectious neurological diseases, such as neurocysticercosis, neuroborreliosis, or herpes viral infection. The aim of this study was to identify tuberculosis (TB) in cases of meningitis with clinical and laboratory evidence suggestive of TBM, and to confirm our findings with molecular tests for TB infection. We recruited patients with neurological symptoms who were examined at the neurology services of Hospitals of Instituto Mexicano del Seguro Social (IMSS) in Mexico City. A total of 144 consecutive patients with suggestive infectious meningitis were initially included; 94 cases of meningitis with clinical and laboratory evidence suggestive of TBM were included, but only 50 of these cases fulfilled the criteria for probable TBM. As the controls, we included 50 cases of meningitis with clinical and laboratory evidence suggestive of non-TBM. Cerebrospinal fluid (CSF) was collected from all 100 patients (cases and controls) and tested for TB by multiplex and nested PCR analyses. Nested PCR detected 0.1 fg of M. tuberculosis DNA. TB infection was confirmed with molecular tests in 49 patients from the 50 cases suggestive of TBM and in 1 of the 50 non-TBM cases. The analysis exhibited a sensitivity of 98.0%, a specificity of 92.0%, a positive predictive value of 88.0% and a negative predictive value of 98.0%. The use CSF for the analyses proved to be effective for the rapid diagnosis of TBM using a developed system of multiplex and nested PCR analyses in patients presenting neurological symptoms.

Estimation of cerebrospinal fluid cortisol level in tuberculous meningitis

BACKGROUND

Central nervous system (CNS) involvement in tuberculosis is around 5-10%. Of the various manifestations of CNS tuberculosis, meningitis is the most common (70-80%). Delay in diagnosis and treatment results in significant morbidity and mortality.

OBJECTIVE

To study the cerebrospinal fluid (CSF) cortisol levels in tubercular meningitis and compare the levels with controls.

METHODS

Cross-sectional, prospective, observational, hospital-based study done in 20 patients of tubercular meningitis, 20 patients of aseptic meningitis (AM) and 25 control subjects without any preexisting neurological disorders who have undergone lumbar puncture for spinal anesthesia.

RESULTS

Cortisol was detected in all 40 CSF samples of patients (100%). Mean CSF cortisol level was 8.82, 3.47 and 1.05 in tubercular meningitis, AM and controls, respectively. Mean CSF cortisol level in tubercular meningitis was significantly higher as compared to AM and controls (P < 0.0001).

CONCLUSION

Cortisol level estimation in CSF is one of the rapid, relatively inexpensive diagnostic markers in early identification of tubercular meningitis along with CSF findings of elevated proteins, hypoglycorrhachia and lymphocytic pleocytosis. This aids in earlier institution of appropriate treatment and thereby decreasing morbidity and mortality. This is the first study on the estimation of CSF cortisol level in tuberculous meningitis.

Elevated host lipid metabolism revealed by iTRAQ-based quantitative proteomic analysis of cerebrospinal fluid of tuberculous meningitis patients

PURPOSE

Tuberculous meningitis (TBM) remains to be one of the most deadly infectious diseases. The pathogen interacts with the host immune system, the process of which is largely unknown. Various cellular processes of Mycobacterium tuberculosis (MTB) centers around lipid metabolism. To determine the lipid metabolism related proteins, a quantitative proteomic study was performed here to identify differential proteins in the cerebrospinal fluid (CSF) obtained from TBM patients (n = 12) and healthy controls (n = 12).

METHODS

CSF samples were desalted, concentrated, labelled with isobaric tags for relative and absolute quantitation (iTRAQ™), and analyzed by multi-dimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS). Gene ontology and proteomic phenotyping analysis of the differential proteins were conducted using Database for Annotation, Visualization, and Integrated Discovery (DAVID) Bioinformatics Resources. ApoE and ApoB were selected for validation by ELISA.

RESULTS

Proteomic phenotyping of the 4 differential proteins was invloved in the lipid metabolism. ELISA showed significantly increased ApoB levels in TBM subjects compared to healthy controls. Area under the receiver operating characteristic curve analysis demonstrated ApoB levels could distinguish TBM subjects from healthy controls and viral meningitis subjects with 89.3% sensitivity and 92% specificity.

CONCLUSIONS

CSF lipid metabolism disregulation, especially elevated expression of ApoB, gives insights into the pathogenesis of TBM. Further evaluation of these findings in larger studies including anti-tuberculosis medicated and unmedicated patient cohorts with other center nervous system infectious diseases is required for successful clinical translation.

rpoB gene high-resolution melt curve analysis: a rapid approach for diagnosis and screening of drug resistance in tuberculous meningitis

Timely and rapid diagnosis of multidrug resistance in tuberculous meningitis (TBM) is a challenge both for a microbiologist and neurologist. The present study was conducted to evaluate role of real-time polymerase chain reaction (PCR) using rpoB, IS6110, and MPB64 as targets in diagnosis of TBM in 110 patients and subsequent high-resolution melt (HRM) curve analysis of rpoB gene amplicons for screening of drug resistance. The sensitivity of smear, culture, and real-time PCR was 1.8%, 10.9%, and 83.63%, respectively. All 120 control patients showed negative results. With HRM rpoB analysis, rifampicin resistance was detected in 3 out of 110 cases of TBM (3.33%). Subsequently, results of HRM analysis were confirmed by rpoB gene sequencing, and mutations were observed at 516 (2 patients) and 531 (1 patient) codons, respectively. rpoB HRM analysis can be a promising tool for rapid diagnosis and screening of drug resistance in TBM patients in 90minutes.

iTRAQ-based quantitative proteomic analysis of cerebrospinal fluid reveals NELL2 as a potential diagnostic biomarker of tuberculous meningitis

Tuberculous meningitis (TBM) is a serious complication of tuberculosis that affects the central nervous system. As TBM may result in permanent sequelae and death, rapid, accurate diagnostic tests using novel biomarkers are required for the early diagnosis and treatment of TBM. A quantitative proteomic study was therefore performed to identify differential proteins in the cerebrospinal fluid (CSF) obtained from TBM patients (n=12) and healthy controls (n=12). CSF samples were labelled with iTRAQ™ and analyzed by LC-MS/MS. Gene ontology and Pathway analysis were conducted using DAVID bioinformatics resources. Neural epidermal growth factor-like like 2 (NELL2) with the largest fold-change value was selected for validation by western blotting. Proteomic phenotyping revealed over-representation in two inflammation-associated processes, complement and coagulation cascades as well as cell adhesion molecules. Western blotting showed a significant decrease in NELL2 levels in TBM subjects compared to healthy controls. The AUC analysis revealed NELL2 was able to distinguish TBM subjects from healthy controls with 83.3% sensitivity and 75% specificity. In conclusion, the results showed that CSF NELL2 is a potential diagnostic biomarker for TBM. Further evaluation of these findings in larger studies including anti-tuberculosis medicated and unmedicated patient cohorts with other intracranial infectious diseases is required for clinical translation.

Prospective Analysis of 55 Cases of Tuberculosis Meningitis (TBM) in North India

INTRODUCTION

To assess the clinical profile, laboratory and neuroimaging data of adult tuberculous meningitis (TBM) patients and to determine the predictors of mortality.

MATERIALS AND METHODS

A total of 55 TBM patients and 60 controls were enrolled in this prospective study. Detailed clinical, radiological, biochemical and microbiological evaluation was performed.

STATISTICAL ANALYSIS

Done using SPSS 15.0 for Windows. P value of <0.05 was considered to be significant.

RESULTS

61.8% were males and majority of the study subjects belonged to age group of 21-40 years. Duration of symptoms in all cases was >14 days and commonly included fever, headache, neck rigidity, altered sensorium and vomiting. Biochemical features of cerebrospinal fluid (CSF) showed significant results where 94.5%, 85.45%,83.63% and 81.81% of patients showed CSF sugar levels <2/3 corresponding blood sugar, proteins>100mg%, CSF total leucocyte count of >20 cells/mm(3) and ADA >9.5IU/L respectively while neuroimaging revealed hydrocephalus, basal exudates and meningeal enhancement as significant findings. More than half of TBM patients presented in stage II of disease and overall mortality was 43.63%. A model for prediction of mortality in TBM cases was framed which included variables of age>40 years, past history of tuberculosis (TB), presence of basal exudates and hydrocephalus.

CONCLUSION

TBM is a serious extrapulmonary form of TB and should arise suspicion in mind of clinician based on clinical, laboratory and radiologic results. Further, a model for prediction of mortality in such patients may be helpful for early intervention and better prognosis.

Diagnostic efficacy of adenosine deaminase levels in cerebrospinal fluid in patients of tubercular meningitis: A comparison with PCR for Mycobacterium Tuberculosis

Background

The rapid diagnosis of Tubercular meningitis (TBM) is fundamental to clinical outcome. The key to diagnosis lies in Cerebrospinal fluid (CSF) analysis and radiological investigations. There are numerous lacunae in the confirmation of diagnosis of TBM from CSF.

Purpose

The aim of present study was to compare the efficacy of CSF adenosine deaminase (ADA) level assays and Polymerase chain reaction (PCR) for Mycobacterium tuberculosis (M. tuberculosis) in the diagnosis of TBM.

Methods

Fifty four adult patients with suspected TBM and 37 controls were included in the study and CSF analyzed for ADA and PCR for M. tuberculosis. The cases were subdivided into definite (5), highly probable (22), probable (22) and possible TBM (5) as per previously validated criteria. The first two were grouped as "most likely" TBM (27) and last two as "unconfirmed" TBM (27).

Results

The mean ADA of the "most likely" TBM was 29±24, "unconfirmed" TBM was 21 ± 15 and controls were 4.8±2.2 U/L. The ADA levels correlated with CSF proteins, absolute lymphocyte count and the staging of the disease. Using a cut off level of >L10 U/L, CSF ADA had a sensitivity of 92.5% and specificity of 97%. PCR for M. tuberculosis was positive in 12 out of 27 "most likely" TBM cases, 5 out of 27 "unconfirmed" TBM cases and 3 out of 37 controls. PCR for M. tuberculosis had a sensitivity of 44.5% and specificity of 92% in the "most likely" TBM cases. Conclusions: ADA is a rapid, inexpensive and sensitive test in the diagnosis of TBM. It is more sensitive than AFB smear and culture. PCR is another rapid test in the diagnosis of TBM with a good specificity, even in those patients already on presumptive anti-tuberculous treatment. However, despite the sensitivity and specificity of CSF ADA, it should be corroborated with AFB smear and CSF PCR.

Multi-slice computed tomography 5-minute delayed scan is superior to immediate scan after contrast media application in characterization of intracranial tuberculosis

Background

The aim of this study was to determine whether the diagnosis of intracranial tuberculosis (TB) can be improved when multi-slice computed tomography (MSCT) scans are taken with a 5-min delay after contrast media application.

Material/Methods

Pre- and post-contrast CT scans of the head were obtained from 30 patients using a 16-slice spiral CT. Dual-phase acquisition was performed immediately and 5 min after contrast agent injection. Diagnostic values of different images were compared using a scoring system applied by 2 experienced radiologists.

Results

We found 526 lesions in 30 patients, including 22 meningeal thickenings, 235 meningeal tuberculomas/tubercles, and 269 parenchymal tuberculomas/tubercles. Images obtained with 5-min delayed scan time were superior in terms of lesion size and meningeal thickening outlining in all disease types (P<0.01). The ability to distinguish between vascular sections from the cerebral sulcus and tubercle was also improved (P<0.01).

Conclusions

Image acquisition with 5-min delay after contrast agent injection should be performed as a standard scanning protocol to diagnose intracranial TB.

Detection of Delta-like 1 ligand for the diagnosis of tuberculous meningitis: An effective and rapid diagnostic method

OBJECTIVE

To investigate the diagnostic value of Delta-like 1 ligand (DLL1) in cerebrospinal fluid (CSF) and serum, in tuberculous meningitis (TBM).

METHODS

Patients with a definite diagnosis of central nervous system infection (TBM, viral meningitis/encephalitis or bacterial meningitis) were prospectively enrolled alongside patients with intracranial metastatic tumour and patients with no diagnosis (who served as controls). DLL1 content in CSF and serum was measured quantitatively by enzyme-linked immunosorbent assay; analyses were blinded.

RESULTS

A total of 173 patients were enrolled: 62 with TBM; 38 with viral meningitis/encephalitis; 26 with bacterial meningitis; 17 with intracranial metastatic tumour; 30 with no diagnosis. CSF DLL1 content was highest for TBM; there were no differences in CSF DLL1 between the other groups. Serum DLL1 content was highest for the TBM and intracranial metastatic tumour groups, with significant differences between the TBM group and the viral meningitis/encephalitis, bacterial meningitis and nondiagnosed groups. There were no differences in serum DLL1 between the viral meningitis/encephalitis, bacterial meningitis and nondiagnosed groups, or between the TBM group and the tumour group.

CONCLUSION

As a new biomarker, DLL1 may be of great clinical importance in the diagnosis of TBM.

Childhood acute non-traumatic coma: aetiology and challenges in management in resource-poor countries of Africa and Asia

OBJECTIVE

This review examines the best available evidence on the aetiology of childhood acute non-traumatic coma in resource-poor countries (RPCs), discusses the challenges associated with management, and explores strategies to address them.

METHODS

Publications in English and French which reported on studies on the aetiology of childhood non-traumatic coma in RPCs are reviewed. Primarily, the MEDLINE database was searched using the keywords coma, unconsciousness, causality, aetiology, child, malaria cerebral, meningitis, encephalitis, Africa, Asia, and developing countries.

RESULTS

14 records were identified for inclusion in the review. Cerebral malaria (CM) was the commonest cause of childhood coma in most of the studies conducted in Africa. Acute bacterial meningitis (ABM) was the second most common known cause of coma in seven of the African studies. Of the studies in Asia, encephalitides were the commonest cause of coma in two studies in India, and ABM was the commonest cause of coma in Pakistan. Streptococcus pneumoniae was the most commonly isolated organism in ABM. Japanese encephalitis, dengue fever and enteroviruses were the viral agents most commonly isolated.

CONCLUSION

Accurate diagnosis of the aetiology of childhood coma in RPCs is complicated by overlap in clinical presentation, limited diagnostic resources, disease endemicity and co-morbidity. For improved outcomes, studies are needed to further elucidate the aetiology of childhood coma in RPCs, explore simple and practical diagnostic tools, and investigate the most appropriate specific and supportive interventions to manage and prevent infectious encephalopathies.

Directly observed treatment, short course in tuberculous meningitis: Indian perspective

Background:

Effectiveness of intermittent short course chemotherapy for tuberculous meningitis (TBM) has not been well studied. There are scarce reported studies on this issue in the world literature. Neurologists all over India are reluctant to accept Directly Observed Treatment Short course (DOTS) for TBM since its introduction in India.

Aim:

We did a prospective study to assess effectiveness of Revised National TB Control Program (RNTCP-DOTS) regimes among TBM patients.

Materials and Methods:

In this study we include the TBM patients admitted from September 2008 to March 2011. All were referred to RNTCP for treatment. Diagnostic Algorithm as per RNTCP guidelines was strictly followed and treatment outcome and follow-up status were recorded. We exclude HIV and pediatric age group.

Results:

A total of 42 cases registered for DOTS regimen were included in the study, of which 35 completed the treatment (83%). All the patients were started with DOTS but finally 78% received actual DOTS. All patients were given 9 months intermitted regimen as per RNTCP guidelines. Seven patients died during the treatment (16%).

Conclusion:

We found intermitted short course chemotherapy was effective in TBM.

Clinical and laboratory factors in the differential diagnosis of tuberculous and cryptococcal meningitis in adult HIV-negative patients

Objective It is difficult to make the differential diagnosis between tuberculous meningitis (TBM) and cryptococcal meningitis (CM) when the smear is negative. The objective of this study was to create a diagnostic rule for differentiating TBM from CM in adult HIV-negative patients based on clinical and laboratory features. Methods The clinical and laboratory data of 219 adult HIV-negative patients satisfying the diagnostic criteria for tuberculous (n=100) and cryptococcal (n=119) meningitis hospitalized at the Third Affiliated Hospital of Sun Yat-Sen University during the period 2000-2009 were retrospectively analyzed. Features found to be independently predictive of tuberculous meningitis were modeled using a multivariate logistic regression to create a diagnostic rule. The performance of the diagnostic rule was assessed using a prospective test data method. Results Six factors were found to be predictive of a diagnosis of tuberculous meningitis: gender, mental disorders, vision and/or hearing damage, proteins in the cerebrospinal fluid, the total cerebrospinal fluid white cell count and the coexistence of tuberculosis in peripheral organs. The diagnostic rule developed using these features exhibited 78.0% sensitivity, 95.2% specificity, 92.9% positive predictive value and 84.4% negative predictive value. The corresponding values for the diagnostic rule were 70.0% and 88.0% using prospective test data. Conclusion Clinical and laboratory features can be helpful in the differential diagnosis of tuberculous meningitis and cryptococcal meningitis in adult HIV-negative patients.

The Diagnostic Utility of Bact/ALERT and Nested PCR in the Diagnosis of Tuberculous Meningitis

OBJECTIVE

The early laboratory diagnosis of Tuberculous Meningitis (TBM) is crucial, to start the antitubercular chemotherapy and to prevent its complications. However, the conventional methods are either less sensitive or time consuming. Hence, the diagnostic potentials of BacT/ALERT and Polymerase Chain Reaction (PCR) was evaluated in this study.

MATERIAL AND METHOD

The study group comprised of 62 cases and 33 controls. The cases were divided according to Ahuja's criteria into the confirmed (two cases), highly probable (19 cases), probable (26 cases) and the possible (15 cases) subgroups. Ziehl Neelsen's (ZN) and Auramine Phenol (AP) staining, Lowenstein Jensen (LJ) medium culture, BacT/ALERT and nested Polymerase Chain Reaction (PCR) which targeted IS6110 were carried out on all the patients.

OBSERVATION AND RESULTS

The sensitivity of the LJ culture was 3.22%. BacT/ALERT showed a sensitivity and a specificity of 25.80% and 100% and those of nested PCR were found to be 40.32% and 96.97% respectively. The mean detection time of growth of the LJ culture was 31.28 days, whereas that of BacT/ALERT was 20.68 days. The contamination rate in the LJ culture and BacT/ALERT were 7.2% and 5.8% respectively.

CONCLUSION

Nested PCR was found to be more sensitive, followed by BacT/ALERT as compared to the LJ culture and smear microscopy. As both false negative and false positive results have been reported for nested PCR, so it should not be used alone as a criterion for initiating or terminating the therapy, but it should be supported by clinical, radiological, cytological and other microbiological findings.

Comparison of real time IS6110-PCR, microscopy, and culture for diagnosis of tuberculous meningitis in a cohort of adult patients in Indonesia

BACKGROUND

Bacteriological confirmation of tuberculous (TB) meningitis is difficult. Culture is slow and microscopy has insufficient sensitivity. We evaluated real time PCR targeting insertion sequence IS6110 among 230 consecutive adult patients with subacute meningitis in a referral hospital in Indonesia.

METHODS

Cerebrospinal fluid (CSF) samples were examined using microscopy, solid and liquid culture, and real time IS6110-PCR with a fluorescence-labeled probe using DNA extracted from CSF. CSF samples from 40 non-infectious neurology patients were used as negative controls. IS6110-PCR results were linked with clinical and CSF characteristics.

RESULTS

Most patients presented with subacute meningitis, after a median of 14 days of symptoms (range 7-30). After exclusion of cryptococcal and bacterial meningitis, 207 patients were classified as definite or probable TB meningitis; 17.9% with HIV infection. Among this group IS6110-PCR gave the highest positivity rate (68%, 95% CI 62-74%) compared with microscopy of ZN-stained slides (11%, 95% CI 7-15%), and mycobacterial culture using solid (36%, 95% CI 29-42%) and liquid (44%, 95% CI 37-51%) media. IS6110-PCR was positive in 92% of patients with culture-positive and 42% of patients with culture-negative probable TB meningitis. Among culture-negative patients, a positive PCR was associated with a history of TB treatment, a longer duration of illness, a higher CSF cell count and protein, and a lower CSF glucose. IS6110-PCR was negative in all CSF samples from non-meningitis control patients.

CONCLUSIONS

Real time IS6110-PCR is a quick, sensitive, and specific test for diagnosing of TB meningitis in this setting. Its performance in other (less-developed) settings needs further study.

Validation of diagnostic algorithm to differentiate between tuberculous meningitis and acute bacterial meningitis

BACKGROUND

Discrimination between tuberculous and acute bacterial meningitis is difficult by clinical features alone and laboratory methods may only supplement the clinical suspicion. We aimed to validate the diagnostic criteria by Thwaites et al. [1] and construct our own diagnostic predictors based on the clinical and laboratory features.

METHODS

380 patients of acute bacterial meningitis (ABM) and 210 patients of tuberculous meningitis (TBM) were enrolled retrospectively from June 2004 to June 2007 and prospectively from July 2007 to September 2008. HIV positive patients were excluded. Detailed history, clinical examination CSF analysis, haematological, biochemical investigations and imaging was performed in all patients.

RESULTS

Factors associated with the diagnosis of TBM in the present study included rural area of residence, longer duration of disease, presence of clear CSF, lower percentage of CSF neutrophils, presence of diplopia and hemiparesis. On validation, age did not appear as a significant factor in our population. The diagnostic algorithm from our study group had a sensitivity of 95.71% and specificity of 97.63%.

CONCLUSIONS

The diagnostic criterion has a fair validation in our population when the age factor is excluded. The rule is useful in HIV negative patients with low CSF sugar and negative organism yield in the CSF.

Brain tuberculomas, tubercular meningitis, and post-tubercular hydrocephalus in children

Central nervous system tuberculosis in children presents commonly as tubercular meningitis, post-tubercular meningitis hydrocephalus, and much more rarely as space-occupying lesions known as tuberculomas. The occurrence of this condition, though previously reported only in the developing world, is now frequently reported in human immunodeficiency virus positive migrants in the western world. The exact pathogenesis of this condition is still incompletely understood, and the mainstay of treatment is chemotherapeutic regimes. Neurosurgical intervention is rarely necessary, and is confined to cases of hydrocephalus after tubercular meningitis and to large tubeculomas with space-occupying effects.

Sensitivity and specificity of immunocytochemical staining of mycobacterial antigens in the cytoplasm of cerebrospinal fluid macrophages for diagnosing tuberculous meningitis

The sensitivity and specificity of immunocytochemical staining of mycobacterial antigens in the cytoplasm of cerebrospinal fluid (CSF) macrophages for diagnosis of tuberculous meningitis (TBM) was prospectively compared with Ahuja criteria from 393 consecutive CSF specimens. The assay can play an important role for the diagnosis of TBM, with sensitivity of 73.5% and specificity of 90.7%.

Multiplex PCR for rapid diagnosis of tuberculous meningitis

Rapid and specific diagnosis of tubercular meningitis is of paramount importance to decrease morbidity and mortality. The aim of the study was to evaluate multiplex PCR using protein b, MPB 64, and IS6110 primers directed against M. tuberculosis complex for the diagnosis of tuberculous meningitis (TBM). Multiplex PCR was performed on 18 TBM confirmed cases (culture was positive), 92 clinically suspected TBM cases and 100 non-TBM (control group) patients. Multiplex PCR had a sensitivity of 94.4% for confirmed cases and specificity of 100% for confirmed TBM cases. In 92 clinically diagnosed but unconfirmed TBM cases, multiplex PCR was positive in 84.78% cases. The overall sensitivity of microscopy, culture and multiplex cases were 1.81, 16.73, and 86.63% and specificity was 100, 100, and 100% respectively. Multiplex PCR using protein b, MPB 64, and IS6110 primers has a high sensitivity and specificity in diagnosis of tubercular meningitis.

Prognostic factors predicting a fatal outcome in HIV-negative children with neurotuberculosis

OBJECTIVE

To identify prognostic factors predicting a fatal outcome in HIV-negative children with neurotuberculosis based on clinical, epidemiological, and laboratory findings.

METHOD

The clinical records of all in-patients diagnosed with neurotuberculosis from 1982 to 2005 were evaluated retrospectively. The following prognostic parameters were examined: gender, age, close contact with a tuberculosis-infected individual, vaccination for bacillus Calmette-Guérin, purified protein derivative (PPD) of tuberculin results, concomitant miliary tuberculosis, seizures, CSF results, and hydrocephalus.

RESULTS

One hundred forty-one patients diagnosed with neurotuberculosis were included. Seventeen percent of the cases resulted in death. The factors that were correlated with a negative outcome included lack of contact with a tuberculosis-infected individual, negative PPD reaction, coma, and longer hospitalisation time. A multiple logistic regression analysis was performed to identify which of these factors most often resulted in death.

CONCLUSION

Coma at diagnosis, lack of tuberculosis contact, and a non-reactive PPD were the most important predictors of fatality in patients with neurotuberculosis.

Hypothalamic pituitary abnormalities in tubercular meningitis at the time of diagnosis

Tubercular meningitis (TBM) is the most dreaded form of extra pulmonary tuberculosis associated with high morbidity and mortality. Various hypothalamic pituitary hormonal abnormalities have been reported to occur years after recovery from disease but there are no systematic studies in the literature to evaluate the pituitary hypothalamic dysfunction in patients with TBM at the time of presentation. Therefore, the present study was designed to evaluate hypothalamic pituitary abnormalities in newly diagnosed patients with TBM. Patient case series. This prospective study included 75 untreated adult patients with TBM diagnosed as "definite", "highly probable" and "probable" TBM by Ahuja's criteria and in clinical stage 1, 2 or 3 at the time of presentation to hospital. Basal hormonal profile was measured by electrochemilumniscence technique for serum cortisol, luetinizing hormone (LH), follicular stimulating hormone (FSH), prolactin (PRL), thyrotropin (TSH), free tri-iodothyronine (fT3), and free thyroxine (fT4). All patients were subjected to MRI to image brain and hypothalamic pituitary axis and CT for adrenal glands. Thirty-two (42.7%) cases showed relative or absolute cortisol insufficiency. Twenty-three (30.7%) cases showed central hypothyroidism and 37 (49.3%) cases had hyperprolactinemia. No patient had evidence of diabetes insipidus. Multiple hormone deficiency was seen in 22 (29.3%) cases. MRI of hypothalamic pituitary axis using dynamic scanning and thin cuts revealed abnormalities in 10 (13.3%) of the cases. CT adrenal gland was normal in all the patients. Tubercular meningitis is associated with both hormonal and structural abnormalities in the hypothalamic pituitary axis at the time of diagnosis.

Role of the BACTEC radiometric method in the evaluation of patients with clinically probable tuberculous meningitis

Background:

Confirmation of tuberculous meningitis (TBM) and initiation of treatment are often delayed due to limitations in isolating Mycobacterium tuberculosis from cerebrospinal fluid (CSF).

Objectives:

To evaluate the role of the BACTEC radiometric method in a clinical setting for the early diagnosis of TBM.

Materials and Methods:

Patients meeting criteria for clinically probable TBM over a 3 year period were included. Clinical features, results of CSF investigations (protein, glucose, cell count, Ziehl-Neelsen staining, culture in Löwenstein-Jensen (LJ) medium and BACTEC) and brain CT imaging were reviewed. Drug sensitivity was tested using BACTEC. Patients were started on standard treatment and functional outcome, and response at discharge and follow-up were assessed. Patients were divided according to whether or not M. tuberculosis was isolated by BACTEC and the clinical, radiological, and laboratory features compared.

Results:

Sixty patients were evaluated. The mean age was 30 years ± 11.7 years. Headache and fever were the most common symptoms and the mean duration was 26 days. CT findings were hydrocephalus (n=21), basal exudates (n=16), and tuberculoma (n=14). In 40 patients, M. tuberculosis was isolated by BACTEC and average 15 days was required for detection, whereas it was 30 days in LJ medium. Results of drug-sensitivity testing (n=32) were obtained average 7 days after isolation. Patients from whom M. tuberculosis had been isolated by BACTEC more often had tuberculomas in CT imaging (P=0.018).

Conclusion:

Use of the BACTEC method allows early confirmation in patients with clinically probable TBM. It can guide clinicians in the rational use of anti-tuberculosis treatment by confirming diagnosis and identifying drug- sensitivity.

Prognostic factors of tuberculous meningitis in adults: a 6-year retrospective study at a tertiary hospital in northern Taiwan

BACKGROUND/PURPOSE

To investigate the clinical features, laboratory test results, imaging data, and prognostic predictors of tuberculous meningitis (TBM) in adults.

METHODS

We retrospectively reviewed 108 adult patients with a diagnosis of TBM over a 6-year period. Patients were divided into "definite" and "probable" groups, depending on the diagnosis made by (1) positive culture, or polymerase chain reaction, of Mycobacterium tuberculosis (TB) from the cerebrospinal fluid (CSF); or (2) the isolation of TB elsewhere, or chest radiography consistent with active pulmonary TB, or imaging studies of the brain consistent with TBM, or clinical improvement on treatment. These two groups were compared for their clinical features, images, laboratory test results, and 9-month mortality rates to identify prognostic predictors.

RESULTS

Compared with the "probable" group (n = 62), the "definite" group (n = 46) had a higher mortality rate (50.0%vs. 30.6%, p = 0.041) and more consciousness disturbance (78.3%vs. 51.6%, p = 0.005), hydrocephalus (63.4%vs. 40.7%, p= 0.029) and isolation of TB from extra-CSF specimens (41.3%vs. 22.6%, p = 0.037). Old age (p = 0.002), consciousness change (p = 0.032), and hydrocephalus (p = 0.047) were poor prognostic indicators in the "definite" group as assessed by univariate analysis. Severity of TBM at admission and delayed anti-TB therapy resulted in a poor prognosis for all patients. Multiple logistic regression analysis showed that old age and hydrocephalus were independent factors for mortality. Adjunctive steroid therapy over 2 weeks improved survival in both the "definite" (p = 0.002) and "probable" (p = 0.035) groups, but more than 4 weeks of use had no significant effect on mortality. Steroid treatment, therefore, may improve the outcome of patients with TBM.

CONCLUSION

Old age, advanced stage of TBM at admission, hydrocephalus, and positive TB culture or polymerase chain reaction of CSF are factors associated with a poor prognosis for TBM. Early diagnosis and treatment, including short term steroid use, are mandatory for clinical care of adult patients with TBM.

To compare CSF adenosine deaminase levels and CSF-PCR for tuberculous meningitis

This study was planned to compare the adenosine deaminase (ADA) levels and polymerase chain reaction (PCR) in cerebrospinal fluid (CSF) as a rapid method to diagnose tuberculosis meningitis (TBM). Fifty-four adult patients with suspected TBM and 37 controls were included in this study. The median ADA level was 21U/L of most likely TBM, 14U/L of unconfirmed TBM and 5U/L of controls. PCR for Mycobacterium tuberculosis was positive in 12 out of 27 most likely TBM cases, 5 out of 27 unconfirmed TBM cases and 3 out of 37 controls. Using a cut off level of >10U/L, CSF-ADA had a sensitivity of 92.5% and specificity of 97% for the diagnosis of TBM. PCR for M. tuberculosis had a sensitivity of 44.5% and specificity 92% in the most likely TBM cases. This study shows that CSF-ADA is a more sensitive indicator than PCR for the diagnosis of M. tuberculosis.

Outcome of ventriculoperitoneal shunt placement in Grade IV tubercular meningitis with hydrocephalus: a retrospective analysis in 95 patients. Clinical article

OBJECT

Hydrocephalus is the most common complication of tubercular meningitis (TBM). Relieving hydrocephalus by ventriculoperitoneal (VP) shunt placement has been considered beneficial in patients in Palur Grade II or III. The role of VP shunt placement in those of Grade IV is controversial and the general tendency is to avoid its use. Some authors have suggested that patients in Grade IV should receive a shunt only if their condition improves with a trial placement of an external ventricular drain (EVD). In the present study, the authors assessed the outcome of VP shunt placement in patients in Grade IV TBM with hydrocephalus to examine the factors predicting outcome and to determine whether a trial with an EVD is absolutely necessary prior to shunt placement.

METHODS

Ninety-five consecutive cases of TBM with hydrocephalus in which the patients underwent VP shunt placement were retrospectively analyzed, and direct VP shunts were placed whenever possible. An EVD was placed first only in the presence of deranged blood parameters. Outcomes were assessed both in the short and long term.

RESULTS

The mean patient age was 17.5 years (range 1-55 years). Fifty-two patients underwent direct VP shunt placement, and the remaining 43 received EVDs first. Overall, 33 and 45% of patients had favorable short- and long-term outcomes, respectively. Age older than 3 years and duration of altered sensorium < or = 3 days were predictive of a favorable short-term outcome. Glasgow Coma Scale score at presentation was predictive of long-term outcome. Of the patients who did not improve with placement of an EVD prior to VP shunt insertion, 24 and 18% had favorable short- and long-term outcomes, respectively; this was not significantly different from the outcome in the patients who underwent direct VP shunt placement.

CONCLUSIONS

Direct VP shunt placement is an effective option in patients with Grade IV TBM with hydrocephalus. Age and duration of altered sensorium are predictive of short-term outcome, while Glasgow Coma Scale score at presentation predicts long-term outcome. Ventriculoperitoneal shunts should be considered even in patients who do not improve with an EVD.

Efficient diagnosis of tuberculous meningitis by detection of Mycobacterium tuberculosis DNA in cerebrospinal fluid filtrates using PCR

Tuberculous meningitis (TBM) is the most devastating form of meningitis and prompt diagnosis holds the key to its management. Conventional microbiology has limited utility and nucleic acid-based methods have not been widely accepted for various reasons. In view of the paucibacillary nature of cerebrospinal fluid (CSF) and the recent demonstration of free Mycobacterium tuberculosis DNA in clinical specimens, the present study was designed to evaluate the utility of CSF 'filtrates' for the diagnosis of TBM using PCR. One hundred and sixty-seven CSF samples were analysed from patients with 'suspected' TBM (n=81) and a control group including other cases of meningitis or neurological disorders (n=86). CSF 'sediments' and 'filtrates' were analysed individually for M. tuberculosis DNA by quantitative real-time PCR (qRT-PCR) and conventional PCR. Receiver-operating characteristic curves were generated from qRT-PCR data and cut-off values of 84 and 30 were selected for calling a 'filtrate' or 'sediment' sample positive, respectively. Based on these, TBM was diagnosed with 87.6% and 53.1% sensitivity (P<0.001) in 'filtrates' and 'sediments', respectively, and with 92% specificity each. Conventional devR and IS6110 PCR were also significantly more sensitive in 'filtrates' versus 'sediments' (sensitivity of 87.6% and 85.2% vs 31% and 39.5%, respectively; P<0.001). The qRT-PCR test yielded a positive likelihood ratio of 11 and 6.6 by analysing 'filtrate' and 'sediment' fractions, respectively, which establishes the superiority of the 'filtrate'-based assay over the 'sediment' assay. PCR findings were separately verified in 10 confirmed cases of TBM, where M. tuberculosis DNA was detected using devR PCR assays in 'sediment' and 'filtrate' fractions of all samples. From this study, we conclude that (i) CSF 'filtrates' contain a substantial amount of M. tuberculosis DNA and (ii) 'filtrates' and not 'sediments' are likely to reliably provide a PCR-based diagnosis in 'suspected' TBM patients.

Evaluation of cerebral infarction in tuberculous meningitis by diffusion weighted imaging

BACKGROUND

Ischemic complications are known to occur in tuberculous meningitis (TBM). They are usually seen in patients with TBM having a more severe disease. Diffusion weighted imaging (DWI) provides information regarding tissue ischemia at an early stage as compared to conventional magnetic resonance imaging (MRI).

METHODS

Ischemic complications in human immunodeficiency virus (HIV) negative TBM were evaluated using DWI and T2 weighted imaging in 30 patients in the present study. The imaging was performed at baseline within 7 days of admission and in case of any neurological deterioration during follow up. The outcome was assessed by the modified Barthel's index at 1 year follow up. A score of >/=12 was taken as a poor outcome, while a score of <12 was considered as good outcome.

RESULT

Seventeen of these 30 patients had infarcts, and the total number of infarcts seen was 42. Thirty eight lesions were acute/sub acute and four were chronic infarcts. Out of the 38 acute/sub acute infarcts 34 were visible both on T2 weighted imaging and on DWI, while four were seen only on DWI. The volume of infarcts as seen by DWI was significantly larger as compared to conventional T2 weighted imaging (p = 0.019). Six patients had a poor outcome, five from the infarct group and one from the non-infarct group.

CONCLUSION

DWI demonstrates a larger area of infarction and may also be useful in the early detection of infarction. It should be used as an additional sequence along with conventional imaging in patients with TBM while they are on a follow up on anti tuberculous treatment. The information obtained by DWI may be of value in explaining the clinical condition of the patient as well as in the management and prognostication.