The delayed diagnosis of tuberculous meningitis (TBM) leads to poor outcomes, yet the current diagnostic methods for identifying Mycobacterium tuberculosis in cerebrospinal fluid (CSF) are inadequate. The first comparative study of the new GeneXpert MTB/RIF Ultra (Xpert Ultra) for TBM diagnosis suggested increased sensitivity of Xpert Ultra. Two subsequent studies have shown Xpert Ultra has improved sensitivity, but has insufficient negative predictive value to exclude TBM. Collecting and processing large volumes of CSF for mycobacterial testing are important for optimal diagnostic test performance. But clinical, radiological, and laboratory parameters remain essential for TBM diagnosis and empiric therapy is often needed. We therefore caution against the use of Xpert Ultra as a single diagnostic test for TBM; it cannot be used to "rule out" TBM.

Keywords: Ultra; Xpert; cerebrospinal fluid; diagnosis; tuberculous meningitis.

Accurate prediction of atomic-level protein structure is important for annotating the biological functions of protein molecules and for designing new compounds to regulate the functions. Template-based modeling (TBM), which aims to construct structural models by copying and refining the structural frameworks of other known proteins, remains the most accurate method for protein structure prediction. Due to the difficulty in recognizing distant-homology templates, however, the accuracy of TBM decreases rapidly when the evolutionary relationship between the query and template vanishes. In this study, we propose a new method, CEthreader, which first predicts residue-residue contacts by coupling evolutionary precision matrices with deep residual convolutional neural-networks. The predicted contact maps are then integrated with sequence profile alignments to recognize structural templates from the PDB. The method was tested on two independent benchmark sets consisting collectively of 1,153 non-homologous protein targets, where CEthreader detected 176% or 36% more correct templates with a TM-score >0.5 than the best state-of-the-art profile- or contact-based threading methods, respectively, for the Hard targets that lacked homologous templates. Moreover, CEthreader was able to identify 114% or 20% more correct templates with the same Fold as the query, after excluding structures from the same SCOPe Superfamily, than the best profile- or contact-based threading methods. Detailed analyses show that the major advantage of CEthreader lies in the efficient coupling of contact maps with profile alignments, which helps recognize global fold of protein structures when the homologous relationship between the query and template is weak. These results demonstrate an efficient new strategy to combine ab initio contact map prediction with profile alignments to significantly improve the accuracy of template-based structure prediction, especially for distant-homology proteins.

The PARP enzyme and scaffolding protein tankyrase (TNKS, TNKS2) uses its ankyrin repeat clusters (ARCs) to bind a wide range of proteins and thereby controls diverse cellular functions. A number of these are implicated in cancer-relevant processes, including Wnt/β-catenin signalling, Hippo signalling and telomere maintenance. The ARCs recognise a conserved tankyrase-binding peptide motif (TBM). All currently available tankyrase inhibitors target the catalytic domain and inhibit tankyrase's poly(ADP-ribosyl)ation function. However, there is emerging evidence that catalysis-independent "scaffolding" mechanisms contribute to tankyrase function. Here we report a fragment-based screening programme against tankyrase ARC domains, using a combination of biophysical assays, including differential scanning fluorimetry (DSF) and nuclear magnetic resonance (NMR) spectroscopy. We identify fragment molecules that will serve as starting points for the development of tankyrase substrate binding antagonists. Such compounds will enable probing the scaffolding functions of tankyrase, and may, in the future, provide potential alternative therapeutic approaches to inhibiting tankyrase activity in cancer and other conditions.

Poly(ADP-ribosyl)ation (PARylation) catalyzed by the tankyrase enzymes (Tankyrase-1 and -2; a.k.a. PARP-5a and -5b) is involved in mitosis, telomere length regulation, GLUT-4 vesicle transport, and cell growth and differentiation. Together with the E3 ubiquitin ligase RNF146 (a.k.a. Iduna), tankyrases regulate the cellular levels of several important proteins including Axin, 3BP2, and angiomotins, which are key regulators of Wnt, Src and Hippo signaling, respectively. These tankyrase substrates are first PARylated and then ubiquitylated by RNF146, which is allosterically activated by binding to PAR polymer. Each tankyrase substrate is recognized by a tankyrase-binding motif (TBM). Here we show that RNF146 binds directly to tankyrases via motifs in its C-terminal region. Four of these RNF146 motifs represent novel, extended TBMs, that have one or two additional amino acids between the most conserved Arg and Gly residues. The individual RNF146 motifs display weak binding, but together mediate a strong multivalent interaction with the substrate-binding region of TNKS, forming a robust one-to-one complex. A crystal structure of the first RNF146 noncanonical TBM in complex with the second ankyrin repeat domain of TNKS shows how an extended motif can be accommodated in a peptide-binding groove on tankyrases. Overall, our work demonstrates the existence of a new class of extended TBMs that exist in previously uncharacterized tankyrase-binding proteins including those of IF4A1 and NELFE.

OBJECTIVE

We report the frequency of seizure, its possible mechanisms and effect of seizure on the outcome of tuberculous meningitis (TBM).

METHODS

Seventy-nine patients with TBM admitted during 2014-2017 were evaluated. The seizures were categorized as per International League Against Epilepsy as well as into early (within 1 month of meningitis) and late (>1 month) seizure. The possible association of seizures was recorded and the outcome was assessed using modified Rankin Scale (mRS ≤ 2 as good, and mRS>> 2 as poor).

RESULTS

The median age was 27 (18-76) years and 43 (54.4%) of whom were females. Tuberculous meningitis was definite in 31 (39.2%) and highly probable in the remaining. Seizures occurred in 27 (34.2%): early onset in 8 (29.6%) and late in 19 (70.4%) patients. The seizures were focal in 11(13.9%), focal to bilateral in 9 (11.4%), generalised tonic clonic in 7 (8.9%) and status epilepticus in 6 (7.6%) patients. Early seizures were associated with meningeal irritation and late seizures with tuberculoma, infarction and hyponatremia (P = 0.01). Seizure did not affect the mortality but were associated with worse six months outcome (P = 0.03).

CONCLUSIONS

Seizures occurred in 34% patients with TBM and were associated with poor outcome at six months.

To investigate the effect of two different high-dose, step-down prednisolone regimens on body composition in early RA patients after 26 weeks of treatment.

Prednisolone-naive patients with recent-onset RA (n = 108) were randomized to either COBRA (prednisolone 60 mg/day, tapered to 7.5 mg/day in 6 weeks; MTX and SSZ) or COBRA-light therapy (prednisolone 30 mg/day, tapered to 7.5 mg/day in 8 weeks and MTX). Body composition was assessed at baseline (before or soon after start of treatment) and after 26 weeks with DXA, and recorded as total body mass (TBM), total fat mass (FM), total lean mass (LM) and trunk/peripheral fat ratio. Log-ratio analyses assessed the proportional distribution of TBM (between LM, FM and bone mass) and FM (between trunk, extremities and head). The subgroup of patients with a DXA before start of treatment (n = 38) was analysed separately.

In the subgroup of patients with a DXA before start of treatment, TBM increased by 1.6 kg (P < 0.001) and total FM by 1.3 kg (P < 0.001). The trunk/peripheral fat ratio and the proportional distribution of TBM and FM remained stable over time. There were no differences between the treatment groups. Similar results were obtained in the study population as a whole.

Both high-dose, step-down prednisolone regimens caused increases in TBM, mainly caused by an increase in FM, but we found no fat redistribution from peripheral to central tissues. This absence in fat redistribution contradicts the widely held assumption of rapid adverse effects of prednisolone on body composition in RA.

ISRCTNregistry, http://www.isrctn.com, ISRCTN55552928.

OBJECTIVE

Hydrocephalus is a common complication of tuberculous meningitis (TBM) in children. The role of ventriculoperitoneal shunt (VPS) placement in grade IV patients is controversial. The aim of this study is to investigate the clinical value of VPS placement for patients with grade IV TBM with hydrocephalus (TBMH).

METHODS

This study was carried out on children with grade IV TBMH from January 2006 to January 2011 in Xiangya Hospital, China. All patients were given VPS placement combined with medicine treatment. External ventricular drainage (EVD) was performed only in the presence of severe biochemical derangements or brainstem dysfunction requiring correction before shunt surgery. Outcomes were divided into normal, mild sequelae, severe sequelae, death, or vegetable status.

RESULTS

A total of 19 children with grade IV TBMH were recruited into the study. The average follow-up period was 29 months. Three of the 19 patients expired, four patients had a full recovery, eight had slight sequelae, and four had severe sequelae. Six complications related to the shunt surgery were seen among the patients.

CONCLUSIONS

This study demonstrates that direct ventriculoperitoneal shunt surgery could improve the outcome of grade IV TBMH. The response to EVD is not a reliable indication for selecting patients who would benefit from shunt surgery.

OBJECTIVE

There is still no standard protocol for management of patients of tubercular meningitis (TBM) with hydrocephalus in poor neurological grade. In general, a trial of external ventricular drain (EVD) is an accepted method of treatment to decide whether a particular patient will benefit from shunt surgery. However, recent studies suggest that ventriculoperitoneal (VP) shunt may be undertaken without the trial of an EVD. Our study prospectively evaluates the role of direct VP shunt placement in poor grade patients of TBM with hydrocephalus.

METHODS

Twenty-six consecutive pediatric patients of TBM with hydrocephalus in Palur grades III and IV underwent direct VP shunt placement, without prior placement of EVD. Outcome was assessed at the end of 3 months using Glasgow Outcome Score.

RESULTS

The mean age of patients was 3.3 years (range, 4 months to 11 years). Twenty-one (80.8 %) patients were in grade III and five (19.2 %) were in grade IV. Good outcome and mortality in grade IV patients was 20 % (1/5) and 60 % (3/5) respectively; whereas in grade III patients, it was 71.4 % (15/21) and 9.5 % (2/21), respectively. Thirteen patients presented with focal neurological deficit at admission, which persisted in only three patients at 3 months follow up. VP shunt-related complications were observed in six (23.5 %) patients

CONCLUSIONS

Despite poor grade at admission, 71.4 % patients in grade III and 20 % patients in grade IV had a good outcome at 3 months follow-up. Direct VP shunt placement is a safe and effective option even in poor grade patients of TBM with hydrocephalus, with a low complication rate.

OBJECTIVE

This study aims at generating knowledge to understand the conditions in which either of the two procedures (endoscopic third ventriculostomy (ETV) and shunt) are better options and to develop good practice guidelines for the treatment of tubercular meningitis (TBM) hydrocephalus.

METHODS

This study was conducted on 48 patients in pediatric age group (less than or equal to 18 years) of TBM hydrocephalus. The patients were randomized to one of the cerebrospinal fluid diversion procedures (ETV or shunt). The two procedures were compared for their outcome, both radiologically and clinically.

RESULTS

Twenty-four cases underwent shunt, out of which 13 (68%) cases were successful. Twelve (70.3%) cases belonged to grade 3, while one case was of grade 1. In ETV group, 10 (42%) cases had a successful outcome, out of which 7 (38.8%) cases were in grade 3, while 1 case each belonged to grades 1, 2, and 4. Incidence of ETV failure was more in younger age group, i.e., <2 years (n = 7), while no such correlation with age was found in shunt cases.

CONCLUSIONS

Though with the present study it looks like that the relative risk of ETV failure is higher than that for shunt, but the risk becomes progressively lower with time. Therefore, if patients survive the early high-risk period, they could experience a long-term survival advantage devoid of life-long shunt-related complications. Though for definitive comparison, a long-term study is needed.

Mechanical tension along the length of axons, dendrites, and glial processes has been proposed as a major contributor to morphogenesis throughout the nervous system [D. C. Van Essen, Nature 385, 313-318 (1997)]. Tension-based morphogenesis (TBM) is a conceptually simple and general hypothesis based on physical forces that help shape all living things. Moreover, if each axon and dendrite strive to shorten while preserving connectivity, aggregate wiring length would remain low. TBM can explain key aspects of how the cerebral and cerebellar cortices remain thin, expand in surface area, and acquire their distinctive folds. This article reviews progress since 1997 relevant to TBM and other candidate morphogenetic mechanisms. At a cellular level, studies of diverse cell types in vitro and in vivo demonstrate that tension plays a major role in many developmental events. At a tissue level, I propose a differential expansion sandwich plus (DES+) revision to the original TBM model for cerebral cortical expansion and folding. It invokes tangential tension and "sulcal zipping" forces along the outer cortical margin as well as tension in the white matter core, together competing against radially biased tension in the cortical gray matter. Evidence for and against the DES+ model is discussed, and experiments are proposed to address key tenets of the DES+ model. For cerebellar cortex, a cerebellar multilayer sandwich (CMS) model is proposed that can account for many distinctive features, including its unique, accordion-like folding in the adult, and experiments are proposed to address its specific tenets.

Keywords: biomechanics; cerebellum; cerebral cortex; folding; gyrification.

The WHO estimates around a million children contract tuberculosis (TB) annually with over 80 000 deaths from dissemination of infection outside of the lungs. The insidious onset and association with skin test anergy suggests failure of the immune system to both recognise and respond to infection. To understand the immune mechanisms, we studied genome-wide whole blood RNA expression in children with TB meningitis (TBM). Findings were validated in a second cohort of children with TBM and pulmonary TB (PTB), and functional T-cell responses studied in a third cohort of children with TBM, other extrapulmonary TB (EPTB) and PTB. The predominant RNA transcriptional response in children with TBM was decreased abundance of multiple genes, with 140/204 (68%) of all differentially regulated genes showing reduced abundance compared to healthy controls. Findings were validated in a second cohort with concordance of the direction of differential expression in both TBM (r2 = 0.78 p = 2x10-16) and PTB patients (r2 = 0.71 p = 2x10-16) when compared to a second group of healthy controls. Although the direction of expression of these significant genes was similar in the PTB patients, the magnitude of differential transcript abundance was less in PTB than in TBM. The majority of genes were involved in activation of leucocytes (p = 2.67E-11) and T-cell receptor signalling (p = 6.56E-07). Less abundant gene expression in immune cells was associated with a functional defect in T-cell proliferation that recovered after full TB treatment (p<0.0003). Multiple genes involved in T-cell activation show decreased abundance in children with acute TB, who also have impaired functional T-cell responses. Our data suggest that childhood TB is associated with an acquired immune defect, potentially resulting in failure to contain the pathogen. Elucidation of the mechanism causing the immune paresis may identify new treatment and prevention strategies.

With increasingly large numbers of mouse models of human disease dedicated to MRI studies, compromises between in vivo and ex vivo MRI must be fully understood in order to inform the choice of imaging methodology. We investigate the application of high resolution in vivo and ex vivo MRI, in combination with tensor-based morphometry (TBM), to uncover morphological differences in the rTg4510 mouse model of tauopathy. The rTg4510 mouse also offers a novel paradigm by which the overexpression of mutant tau can be regulated by the administration of doxycycline, providing us with a platform on which to investigate more subtle alterations in morphology with morphometry. Both in vivo and ex vivo MRI allowed the detection of widespread bilateral patterns of atrophy in the rTg4510 mouse brain relative to wild-type controls. Regions of volume loss aligned with neuronal loss and pathological tau accumulation demonstrated by immunohistochemistry. When we sought to investigate more subtle structural alterations in the rTg4510 mice relative to a subset of doxycycline-treated rTg4510 mice, ex vivo imaging enabled the detection of more regions of morphological brain changes. The disadvantages of ex vivo MRI may however mitigate this increase in sensitivity: we observed a 10% global shrinkage in brain volume of the post-mortem tissues due to formalin fixation, which was most notable in the cerebellum and olfactory bulbs. However, many central brain regions were not adversely affected by the fixation protocol, perhaps due to our "in-skull" preparation. The disparity between our TBM findings from in vivo and ex vivo MRI underlines the importance of appropriate study design, given the trade-off between these two imaging approaches. We support the utility of in vivo MRI for morphological phenotyping of mouse models of disease; however, for subtler phenotypes, ex vivo offers enhanced sensitivity to discrete morphological changes.

The contribution of immune cells in soft tissue sarcomas (STS) is not completely known and understanding their role is very essential for employing immunotherapy strategies. Here, we show that murine fibrosarcoma-conditioned medium promoted total spleen cell proliferation but inhibited T cell responses to mitogenic and allo-antigen-mediated stimulation. This increased proliferation was found to be in B cells resulting in generation of Breg further leading to Treg population. This was found to be the same in vitro and in vivo. The phenotype of these B cells was CD19⁺CD81⁺CD27⁺CD25⁺PD-L1^hi and they secreted both IL-10 and TGF-β. These tumor evoked Bregs (tBreg), when co-cultured with B depleted T cells, suppressed their proliferation in response to anti-CD3/CD28 stimulation. tBreg-induced suppression of T cell responses was not abrogated by the inhibition or neutralization of IL-10 but by the small molecule inhibitor of TGFβ Receptor type I, SB431542. While SB531542 per se was not cytotoxic to tumor cells, administration of SB431542 in tumor-bearing mice (TBM) significantly reduced the tumor burden. In addition, the treatment significantly reduced Treg cells and rescued proliferation of T cells in response to mitogen and allo-antigen. Collectively, our results identify that tumor evoked Breg cells mediate T cell immune suppression through TGFβ-mediated pathway and that targeting the Breg-Treg axis can be potentially used as an immunotherapy agent.

Keywords: Breg–Treg axis; Fibrosarcoma; Immunosuppression; Regulatory B cell; SB431542; TGF-β signalling.

Quantitative assessment of facial asymmetry is crucial for successful planning of corrective surgery. We propose a tensor-based morphometry (TBM) framework to locate and quantify asymmetry using 3D CBCT images. To this end, we compute a rigid transformation between the mandible segmentation and its mirror image, which yields global rotation and translation with respect to the cranial base to guide the surgery's first stage. Next, we nonrigidly register the rigidly aligned images and use TBM methods to locally analyze the deformation field. This yields data on the location, amount and direction of "growth" (or "shrinkage") between the left and right sides. We visualize this data in a volumetric manner and via scalar and vector maps on the mandibular surface to provide the surgeon with optimal understanding of the patient's anatomy. We illustrate the feasibility and strength of our technique on 3 representative patients with a wide range of facial asymmetries.

Kidney sections from several inbred rat strains were studied with an indirect immunofluorescence technique using five different, selected rat antisera which contained antibodies against the tubular basement membrane (TBM). The sera came from transplanted animals, an apparently normal animal, and animals treated with spleen cells in complete Freund's adjuvant. Upon panel analysis, at least two different antigenic determinants were recognized on the proximal TBM: One was present in nine and one was present in seven of the 15 strains tested; both determinants appear to be expressed in most antigen-positive strains. Using kidneys from major histocompatibility complex (MHC)-congenic strains, it was shown that the TBM antigens are encoded outside the MHC region. Three sera produced variable staining of Bowman's capsule in association with the proximal TBM; two sera produced clearly discordant staining of Bowman's capsule and proximal TBM. The capsular antigens were also coded outside the MHC region. These observations suggested the existence of at least two different antigenic determinants on proximal TBM. Bowman's capsule appeared to have antigenic determinants in common with the proximal TBM as well as distinct determinants.

OBJECTIVE

Simultaneous administration of phenytoin and isoniazid (INH) in tuberculous meningitis (TBM) or tuberculoma patients with seizures results in higher plasma phenytoin level and thus phenytoin intoxication. N-acetyltransferase 2 (NAT2) enzyme catalyses two acetylation reactions in INH metabolism and NAT2 gene polymorphism leads to slow and rapid acetylators. The present study was aimed to evaluate the effect of allelic variants of N-acetyltransferase 2 (NAT2) gene as a predisposing factor for phenytoin toxicity in patients with TBM or tuberculoma having seizures, and taking INH and phenytoin simultaneously.

METHODS

Sixty patients with TBM or tuberculoma with seizures and taking INH and phenytoin simultaneously for a minimum period of seven days were included in study. Plasma phenytoin was measured by high performance liquid chromatography. NAT2 gene polymorphism was studied using restriction fragment length polymorphism and allele specific PCR.

RESULTS

The patients were grouped into those having phenytoin intoxication and those with normal phenytoin level, and also classified as rapid or slow acetylators by NAT2 genotyping. Genotypic analysis showed that of the seven SNPs (single nucleotide polymorphisms) of NAT2 gene studied, six mutations were found to be associated with phenytoin intoxication. For rs1041983 (C282T), rs1799929 (C481T), rs1799931 (G857A), rs1799930 (G590A), rs1208 (A803G) and rs1801280 (T341C) allelic variants, the proportion of homozygous mutant was higher in phenytoin intoxicated group than in phenytoin non-intoxicated group.

CONCLUSIONS

Homozygous mutant allele of NAT2 gene at 481site may act as a predisposing factor for phenytoin intoxication among TBM or tuberculoma patients having seizures.

Anti-tubular basement membrane disease (alpha TBM disease) produces T cell-mediated interstitial nephritis in SJL mice after immunization with renal tubular antigen. Initial mononuclear infiltrates appear in vivo after several weeks, with the subsequent progression to renal fibrosis and end stage renal disease over many months. We have analyzed the fine specificity of the autoreactive helper T cell repertoire in alpha TBM disease through the isolation and characterization of a panel of CD4+ Th1 clones harvested after 1-2 wk from animals immunized to produce disease. All clones capable of mediating alpha TBM disease are directed towards a 14-residue immunodominant epitope (STMSAEVPEAASEA) contained within the target antigen, 3M-1. Evaluation of the T cell receptor (TCR) V beta repertoire used by these autoreactive T cells reveals the use of several V beta genes, but with some preference for V beta 14. Sequencing across the putative CDR3 region of the TCR beta chains suggests that common amino acids at the V beta(N)D beta junction and the D beta(N)J beta junction may contribute to the specific ability of these cells to recognize the immunodominant epitope.

To study the cerebrospinal fluid (CSF) protein profiles of tuberculous meningitis (TBM) and discover potential biomarkers for TBM, differential expression of proteins in the CSF of patients with TBM, patients with cryptococcal meningitis, and a control group were compared using isobaric tags for relative and absolute quantitation labelling (iTRAQ) coupled with 2-dimensional liquid chromatography-tandem mass spectrometry (LC-MS). As a result, a total of 208 unique proteins with a molecular weight ranging from 10 KD to 135 KD were identified and quantified in CSF samples from patients with TBM. Of the proteins, 9 were expressed at levels differing 2.0 fold, 6 were up-regulated, and 3 were down-regulated. These proteins appear to be involved in calcium ion binding, lipoprotein metabolism, immune response, and signal conduction. Two differentially expressed proteins were identified using ELISA. The present study represents the successful use of iTRAQ to examine CSF from patients with TBM. The differentially expressed proteins identified may be potential diagnostic biomarkers and provide valuable insight into the underlying mechanisms of TBM. This study also demonstrated that the differential protein profiles of diseases can be quickly determined using iTRAQ-LC-MS, a potential method for quantitative comparative proteomics.

This prospective study was done over seven years from 1996 to 2003 to investigate the chest computed tomography scan findings along with other radiologic examinations that included chest roentgenography and cranial computed tomography in children with tuberculous meningitis (TBM). Chest roentgenography demonstrated abnormal findings in 32 cases (43%) (hilar adenopathy, 32%; miliary pattern, 18%; bronchopneumonic infiltrate, 24%), while chest computerized tomography was abnormal in 65 cases (88%; p<0.005): mediastinal and hilar lymphadenopathy were present in 46% (p<0.005); miliary pattern, in 23% (p<0.05); and bronchopneumonic infiltrate, in 23% (p<0.05). Cranial computerized tomography was abnormal in 68 cases (92%). Chest computerized tomography scan helps establish the diagnosis of TBM when chest radiography is normal or inconclusive, and it is useful in assessing children with suspected TBM.

OBJECTIVE

To evaluate the diagnostic accuracy of interferon-gamma release assays (IGRAs) for diagnosing tuberculous meningitis (TBM).

METHODS

The EMBASE and PubMed databases were systematically searched to identify studies published by 2 May 2015 investigating the diagnostic accuracy of IGRA for TBM. The quality of the included studies was assessed using the revised Quality Assessment for Studies of Diagnostic Accuracy (QUADAS-2) method. The overall diagnostic accuracies of an IGRA for cerebrospinal fluid (CSF) or blood were pooled using a bivariate model.

RESULTS

Eight studies using blood IGRA and 6 studies using CSF IGRA were included. The overall sensitivities for blood and CSF IGRA were respectively 0.78 and 0.77, and the specificities were 0.61 and 0.88. The areas under the summary receiver operating characteristic curves were respectively 0.76 and 0.83 for blood and CSF IGRA. The major design weaknesses of the studies included were patient selection bias and exclusion of uninterpretable results.

CONCLUSIONS

The diagnostic accuracy of blood and CSF IGRA in case of TBM is moderate.

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.

OBJECTIVE

The study aimed at describing characteristics and outcome of tuberculous meningitis (TBM) in HIV-positive patients and comparing these parameters with those of extrapulmonary TB (TBEP) and pulmonary TB (TBP).

METHODS

Kaplan-Meier estimation and Poisson regression models were used to assess the mortality following TB diagnosis and to evaluate potential prognostic factors for the 3 groups of TB patients separately.

RESULTS

A total of 100 patients with TBM, 601 with TBEP, and 371 TBP were included. Patients with TBM had lower CD4 cell counts and only 17.0% received antiretroviral therapy (ART) at TB diagnosis. The cumulative probability of death at 12 months following TB was 51.2% for TBM (95% CI 41.4-61.6%), 12.3% for TBP (8.9-15.7%), and 19.4% for TBEP (16.1-22.6) (P<0.0001; log-rank test). For TBM, factors associated with a poorer prognosis were not being on ART (adjusted incidence rate ratio (aIRR) 4.00 (1.72-9.09), a prior AIDS diagnosis (aIRR=4.82 (2.61-8.92)), and receiving care in Eastern Europe (aIRR=5.41 (2.58-11.34))).

CONCLUSIONS

TBM among HIV-positive patients was associated with a high mortality rate, especially for patients from Eastern Europe and patients with advanced HIV-infection, which urgently calls for public health interventions to improve both TB and HIV aspects of patient management.