Using monoclonal antibody affinity chromatography, we isolated a 48,000 mol wt, glucose-rich glycoprotein (3M-1) from collagenase-solubilized rabbit renal tubular basement membrane (SRTA). The purified 3M-1 protein is noncollagenous, and is capable of inducing anti-TBM (tubular basement membrane) antibodies and interstitial nephritis in susceptible hosts. Further, when SRTA, at a normally nephritogenic dose, was selectively depleted of 3M-1, it lost its ability to induce disease. As shown by immunofluorescent techniques, 3M-1 appears to be localized on rodent TBM to the exclusion of the glomerular basement membrane, but was lacking in the TBM of the LEW rat, a strain devoid of the relevant antigen of anti-TBM disease. Immunoelectron microscopy revealed that 3M-1 was associated with the most lateral aspect of the TBM, which borders, and lies in the interstitium. These results indicate that 3M-1 is the nephritogenic antigen producing experimental anti-TBM disease.

The causes of the decreased immune responsiveness in tumor-bearing hosts are incompletely understood. The impact of a decreased immune response in cancer patients on the clinical response in immunotherapy trials has not been evaluated. The present report demonstrates a marked decrease in the therapeutic efficacy of adoptively transferred T lymphocytes obtained from murine hosts bearing tumor for greater than 30 days [late tumor-bearing mice (TBM)] as compared with normal mice and mice bearing tumor for less than 21 days (early TBM). In vitro analysis of the functions of the T lymphocytes from late TBM showed an apparently normal proliferative response to anti-CD3 and IL-2 with adequate lymphokine production from CD4+ cells, but a significant decrease in the cytotoxic function of CD8+ cells. The decreased cytotoxicity was not because of cell-mediated suppression. The expression of granzyme B mRNA was significantly delayed and decreased in magnitude in CD8+ cells from late TBM. Culture supernatants from two unrelated tumor cell lines were able to inhibit the cytotoxic activity of normal CD8+ cells in vitro. The tumor-derived suppressive factor is not transforming growth factor-beta (TGF-beta), but it has not been further characterized. The data suggest that one potential mechanism responsible for immunologic defects in patients with large tumor burdens is a tumor-induced defect that compromises the function of CD8+ effector T cells.

BACKGROUND

Tuberculous meningitis is the most severe form of tuberculosis. Mortality for untreated tuberculous meningitis is 100%. Despite the introduction of antibiotic treatment for tuberculosis the mortality rate for tuberculous meningitis remains high; approximately 25% for HIV-negative and 67% for HIV positive patients with most deaths occurring within one month of starting therapy. The high mortality rate in tuberculous meningitis reflects the severity of the condition but also the poor antibacterial activity of current treatment regimes and relatively poor penetration of these drugs into the central nervous system. Improving the antitubercular activity in the central nervous system of current therapy may help improve outcomes. Increasing the dose of rifampicin, a key drug with known poor cerebrospinal fluid penetration may lead to higher drug levels at the site of infection and may improve survival. Of the second generation fluoroquinolones, levofloxacin may have the optimal pharmacological features including cerebrospinal fluid penetration, with a ratio of Area Under the Curve (AUC) in cerebrospinal fluid to AUC in plasma of >75% and strong bactericidal activity against Mycobacterium tuberculosis. We propose a randomized controlled trial to assess the efficacy of an intensified anti-tubercular treatment regimen in tuberculous meningitis patients, comparing current standard tuberculous meningitis treatment regimens with standard treatment intensified with high-dose rifampicin and additional levofloxacin.

METHODS

A randomized, double blind, placebo-controlled trial with two parallel arms, comparing standard Vietnamese national guideline treatment for tuberculous meningitis with standard treatment plus an increased dose of rifampicin (to 15 mg/kg/day total) and additional levofloxacin. The study will include 750 patients (375 per treatment group) including a minimum of 350 HIV-positive patients. The calculation assumes an overall mortality of 40% vs. 30% in the two arms, respectively (corresponding to a target hazard ratio of 0.7), a power of 80% and a two-sided significance level of 5%. Randomization ratio is 1:1. The primary endpoint is overall survival, i.e. time from randomization to death during a follow-up period of 9 months. Secondary endpoints are: neurological disability at 9 months, time to new neurological event or death, time to new or recurrent AIDS-defining illness or death (in HIV-positive patients only), severe adverse events, and rate of treatment interruption for adverse events.

CONCLUSIONS

Currently very few options are available for the treatment of TBM and the mortality rate remains unacceptably high with severe disabilities seen in many of the survivors. This trial is based on the hypothesis that current anti-mycobacterial treatment schedules for TBM are not potent enough and that outcomes will be improved by increasing the CSF penetrating power of this regimen by optimising dosage and using additional drugs with better CSF penetration.

BACKGROUND

International Standard Randomised Controlled Trial Number ISRCTN61649292.

Leaf dark respiration (Rdark ) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of Rdark and associated leaf traits. Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed-effects models were used to disentangle sources of variation in Rdark . Area-based Rdark at the prevailing average daily growth temperature (T) of each site increased only twofold from the Arctic to the tropics, despite a 20°C increase in growing T (8-28°C). By contrast, Rdark at a standard T (25°C, Rdark (25) ) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher Rdark (25) at a given photosynthetic capacity (Vcmax (25) ) or leaf nitrogen concentration ([N]) than species at warmer sites. Rdark (25) values at any given Vcmax (25) or [N] were higher in herbs than in woody plants. The results highlight variation in Rdark among species and across global gradients in T and aridity. In addition to their ecological significance, the results provide a framework for improving representation of Rdark in terrestrial biosphere models (TBMs) and associated land-surface components of Earth system models (ESMs).

Tingible body macrophages (TBM), long thought simply as scavengers of apoptotic lymphocytes, are located in the unique microenvironment of germinal centers in close proximity to antigen-retaining follicular dendritic cells (FDC). Observations that TBM endocytose FDC-iccosomal (immune-complex coated bodies) antigen suggested that TBM might present this antigen and help regulate the germinal center reaction. To test for antigen presentation, the ovalbumin (OVA)-specific T(H) hybridoma, 3DO-54.8, which produces IL-2 on receiving effective presentation of OVA, were used as responders to OVA-bearing TBM. Results showed that OVA-bearing TBM failed to induce IL-2 production. Furthermore, addition of TBM to IL-2-inducing positive controls (B cells) not only failed to augment IL-2 production, but rather TBM significantly (55-90%) reduced B-cell induction of IL-2. We found that TBM were rich in prostaglandin by comparison with other nongerminal center lymph node macrophages and that addition of indomethacin to the cultures reversed the inhibitory effect of TBM. Depletion of TBM from enriched preparations, prior to addition to positive control cultures, also abrogated the inhibitory effect on IL-2 production. These data support the concept that TBM, within the unique microenvironment of germinal centers, may be specialized to downregulate the germinal center reaction.

BACKGROUND

The I-neb AAD System was designed to deliver aerosol with two different breathing pattern algorithms: the Tidal Breathing Mode (TBM) and the Target Inhalation Mode (TIM). For the purpose of the study, the TBM breathing pattern algorithm was set to guide the subjects to inhalation during tidal breathing with aerosol pulsed during 50-80% of the time spent on inhalation, whereas the TIM breathing pattern was set to guide the subject to a slow and deep inhalation of up to approximately 9 sec with aerosol pulsed for up to 7 sec, leaving 2 sec for particle deposition in the lungs. In TIM, the inspiratory flow was guided to approximately 20 L/min through a built-in resistance in the mouthpiece.

METHODS

We have, in a randomized, open-label, crossover study of 12 healthy subjects evaluated lung deposition following administration of a radiolabeled aerosol from the I-neb AAD System with the TBM and TIM breathing patterns.

RESULTS

The results showed that mean lung deposition was significantly higher when using the I-neb AAD System with the TIM breathing pattern (73.3%) than with the TBM breathing pattern (62.8%). The mean exhaled fractions were low (<1%) for both breathing patterns. The nebulization time was significantly shorter with the TIM breathing pattern (3.0 min) than with the TBM breathing pattern (4.7 min).

CONCLUSIONS

The results of the present study showed that lung deposition with the slow and deep inhalation achieved through the I-neb AAD System in TIM was superior to the lung deposition achieved during tidal breathing in TBM. With the combination of high lung deposition, almost no loss of aerosol during exhalation, and short nebulization time the I-neb AAD System with the TIM breathing pattern should be of special value to patients who require multiple daily dosing of aerosolized medication, are using drugs that should not be wasted into the room air, or would benefit from a more efficient delivery system.

Although tubulointerstitial nephritis with IgG4+ plasma cell (PC) infiltration is a hallmark of IgG4-related kidney disease (IgG4-RKD), only a few studies are available about the minimum number of IgG4+ PC needed for diagnosis along with IgG4+/IgG+ PC ratio in the kidney. In addition, the significance of the deposition of IgG or complement as a reflection of humoral immunity involvement is still uncertain. In this study, we analyzed 20 Japanese patients with IgG4-RKD to evaluate the number of IgG4+ PCs along with IgG4+/IgG+ PC ratio and involvement of humoral immunity. The average number of IgG4+ PCs was 43.8/hpf and the average IgG4+/IgG+ or IgG4+/CD138+ ratio was 53%. IgG and C3 granular deposits on the tubular basement membrane (TBM) were detected by immunofluorescence microscopy in 13% and 47% of patients, respectively. Nine patients had a variety of glomerular lesions, and 7 of them had immunoglobulin or complement deposition in the glomerulus. In conclusion, we confirmed that infiltrating IgG4+ PCs>> 10/hpf and/or IgG4/IgG (CD138)+ PCs>> 40% was appropriate as an item of the diagnostic criteria for IgG4-RKD. A relatively high frequency of diverse glomerular lesions with immunoglobulin or complement deposits and deposits in TBM may be evidence of immune complex involvement in IgG4-related disease.

Anti-tubular basement membrance (alpha TBM) disease-producing interstitial nephritis in mice is not dependent on the generation of alpha TBM antibodies. Susceptibility seems to be defined by very private specificities in H-2K. These specificities are pleiomorphic, providing both immune-response genes and identity restrictions for cytotoxic effector functions expressed by a Thy-1.2+, Lyt-2,3+ T cell. These studies establish a role for T cells in the pathogenesis in interstitial nephritis as well as providing further evidence for the role of H-2K in the expression of an autoimmune disease.

Cerebral infarction (CI) is a serious complication of tuberculous meningitis (TBM). It can be asymptomatic or symptomatic, causing stroke. We studied 40 TBM patients. All had initial CT brain scan, CT/MRI brain scan 3 months later and urgent CT brain scan for deterioration. CI was classified into lacunar infarction (LI) or large artery infarction (LAI). Twelve (30%) had CI, in 9 (23%) it was symptomatic and in 3 (8%) silent. Seven (58%) had LAI +/- LI. Eight (67%) had multiple CI. Two died from brainstem CI and 6 were dependent at 1 year. Patients with LAI might develop posterior circulation CI more frequently than those with LI only. CI is a common complication of TBM locally, with LAI and multiple CI being common. Two thirds of TBM patients complicated by CI had poor prognosis despite adjunctive dexamethasone treatment.

Epithelial-to-mesenchymal transition (EMT) is a process for fully differentiated epithelial cells to undergo a phenotypic change to fibroblasts via diverse intracellular signaling pathways. While the pivotal role of fibroblasts in renal fibrosis is widely accepted, their origin remains undefined. In addition, although a large number of studies have provided evidence of EMT in human kidney diseases, specific signaling pathways leading to EMT have not yet been discovered in humans. To evaluate the origin of interstitial fibroblasts and signaling pathways involved in the EMT process, we analyzed the differential expression of EMT-related molecules in paraffin-fixed sections from 19 human fibrotic kidneys and 4 control kidneys. In human fibrotic kidneys, tubular epithelial cells (TECs) with intact tubular basement membrane (TBM) showed loss or down-regulation of an epithelial marker (E-cadherin), de novo expression of mesenchymal markers (vimentin and fibronectin), and significant up-regulation of inducers and mediators controlling the EMT process (transforming growth factor-β1 (TGF-β1), p-Smad2/3, β1-integrin, p38 mitogen-activated protein kinase (MAPK), WNT5B and β-catenin) in the areas of interstitial inflammation and fibrosis, compared with their expression in control kidneys. In conclusion, the type II EMT process in humans is thought to be an adaptive response of TECs to chronic injury and is regulated by interconnections of TGF-β/Smad, integrin/integrin-linked kinase (ILK) and wnt/β-catenin signaling pathways.

A mononuclear copper(II) superoxo species has been invoked as the key reactive intermediate in aliphatic substrate hydroxylation by copper monooxygenases such as peptidylglycine α-hydroxylating monooxygenase (PHM), dopamine β-monooxygenase (DβM), and tyramine β-monooxygenase (TβM). We have recently developed a mononuclear copper(II) end-on superoxo complex using a N-[2-(2-pyridyl)ethyl]-1,5-diazacyclooctane tridentate ligand, the structure of which is similar to the four-coordinate distorted tetrahedral geometry of the copper-dioxygen adduct found in the oxy-form of PHM (Prigge, S. T.; Eipper, B. A.; Mains, R. E.; Amzel, L. M. Science2004, 304, 864-867). In this study, structures and physicochemical properties as well as reactivity of the copper(I) and copper(II) complexes supported by a series of tridentate ligands having the same N-[2-(2-pyridyl)ethyl]-1,5-diazacyclooctane framework have been examined in detail to shed light on the chemistry dictated in the active sites of mononuclear copper monooxygenases. The ligand exhibits unique feature to stabilize the copper(I) complexes in a T-shape geometry and the copper(II) complexes in a distorted tetrahedral geometry. Low temperature oxygenation of the copper(I) complexes generated the mononuclear copper(II) end-on superoxo complexes, the structure and spin state of which have been further characterized by density functional theory (DFT) calculations. Detailed kinetic analysis on the O(2)-adduct formation reaction gave the kinetic and thermodynamic parameters providing mechanistic insights into the association and dissociation processes of O(2) to the copper complexes. The copper(II) end-on superoxo complex thus generated gradually decomposed to induce aliphatic ligand hydroxylation. Kinetic and DFT studies on the decomposition reaction have suggested that C-H bond abstraction occurs unimolecularly from the superoxo complex with subsequent rebound of the copper hydroperoxo species to generate the oxygenated product. The present results have indicated that a superoxo species having a four-coordinate distorted tetrahedral geometry could be reactive enough to induce the direct C-H bond activation of aliphatic substrates in the enzymatic systems.

Tuberculous meningitis (TBM) is the most common form of chronic infection of the central nervous system. Despite the magnitude of the problem, the general diagnostic outlook is discouraging. Specifically, there is no generally accepted early confirmative diagnosis protocol available for TBM. Various Mycobacterium tuberculosis antigens are now recognized as potential markers for diagnosis of TBM. However, their presence remains questionable, and many of these antigens are reported in the blood but not in the cerebrospinal fluid (CSF). This study identifies a specific protein marker in CSF which will be useful in early diagnosis of TBM. We have demonstrated the presence of a 30-kDa protein band in CSF of 100% (n = 5) of confirmed and 90% (n = 138) of suspected TBM patients out of 153 TBM patients. The 30-kDa band was excised from the gel, destained extensively, and digested with trypsin. The resulting peptides were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Partially purified proteins from CSF samples of TBM were analyzed by two-dimensional polyacrylamide gel electrophoresis and Western blotting. Immunoblotting and enzyme-linked immunosorbent assay (ELISA) were performed to confirm the presence of proteins in the 30-kDa protein band. The antigen 85 (Ag 85) complex was detected in CSF of TBM patients by indirect ELISA using antibodies against Ag 85 complex. The results of this study showed the 30-kDa protein band contained MTB proteins Rv3804c (Ag85A) and Rv1886c (Ag 85B), both members of the Ag85 complex. This was also confirmed by using immunotechniques such as indirect ELISA and the dot immunobinding assay. Detection of Ag85 complex was observed in CSF of 89% (71 out of 80) of suspected TBM patients that were 30-kDa protein positive. The observed 30-kDa protein in the CSF is comprised of the MTB Ag85 complex. This protein was earlier reported to be present in the blood of patients with extra-central nervous system tuberculosis. Therefore, this finding suggests that this protein can be used as a molecular marker for any type of tuberculous infection. It also provides a more sensitive immunoassay option for the early and confirmatory diagnosis of TBM.

An open prospective clinical, microbiological, and molecular analysis of a national molecular diagnostic service for tuberculous meningitis (TBM) using an in-house IS6110-targeted PCR for molecular "Fastrack" diagnosis was carried out. Between April 1997 and June 1998. Consecutive cerebrospinal fluid (CSF) samples from 131 patients were assessed. Against a culture on the same sample, PCR had a sensitivity of 75% and a specificity of 94%. Of samples from patients classified as definite or probable TBM cases based on clinical criteria, 81% had raised CSF protein levels and 73% had a lymphocytosis, although 57% of all submitted samples showed a raised lymphocyte count. While only 46% had a CSF glucose level below the normal range, the CSF glucose level was significantly lower (P = 0. 0281) than in cases of meningitis of other etiologies. Levels of tumor necrosis factor alpha were also found to be significantly raised in definite or probable TBM cases (P = 0.028), while adenosine deaminase levels were not. The study showed IS6110-targeted PCR to be a rapid, sensitive, and specific test in routine use for the diagnosis of TBM.

BACKGROUND

Central airway stabilization with silicone stents can improve respiratory symptoms in patients with severe symptomatic tracheobronchomalacia (TBM) but is associated with a relatively high rate of complications. Surgery with posterior tracheobronchial splinting using a polypropylene mesh has also been used for this condition but to date has not been evaluated prospectively and objectively for patient outcomes.

OBJECTIVE

To evaluate the effect of surgical tracheobronchoplasty on symptoms, functional status, quality of life, lung function, and exercise capacity in patients with severe and symptomatic TBM.

METHODS

A prospective observational study in which baseline measurements were compared to those obtained 3 months after surgical tracheobronchoplasty.

RESULTS

Of 104 referred patients to our complex airway center for severe TBM, 77 had baseline measurements. Of this group, 57 patients had severe malacia and underwent stent placement for central airway stabilization. Of those, 37 patients reported improvement in respiratory symptoms and 35 were considered for surgical tracheobronchoplasty. Two patients were excluded from surgery for medical reasons. Median age was 61 years (range, 39 to 83 years), 20 patients were men, 11 patients (31%) had COPD, 9 patients (26%) had asthma, and 4 patients (11%) had Mounier-Kuhn syndrome. Thirty-three patients (94%) presented with severe dyspnea, 26 patients (74%) with uncontrollable cough, and 18 patients (51%) reported recurrent pulmonary infections. Two patients (3%) presented with respiratory failure requiring mechanical ventilation. After surgery, quality of life scores improved in 25 of 31 patients (p < 0.0001), dyspnea scores improved in 19 of 26 patients (p = 0.007), functional status scores improved in 20 of 31 patients (p = 0.003), and mean exercise capacity improved in 10 patients (p = 0.012).

CONCLUSIONS

In experienced hands, surgical central airway stabilization with posterior tracheobronchial splinting using a polypropylene mesh improves respiratory symptoms, health-related quality of life, and functional status in highly selected patients with severe symptomatic TBM.

The lipid, FA, and sterol composition of the New Zealand green lipped mussel (NZGLM, Perna canaliculus) and of the Tasmanian blue mussel (TBM, Mytilus edulis) were compared using TLC-FID and GC-MS. The respective mussel species were obtained from three different sites in both New Zealand (NZ) and Tasmania. Lipid class distribution of both mussel species was characterized by a high proportion of phospholipid (PL, 57-79%) and TG (10-25%), FFA (7-12%), and sterols (ST, 12-18%). The NZGLM had higher proportions of TG, FFA, and ST (P < 0.01), whereas the TBM had a higher proportion of PL (P < 0.01). There were higher proportions of total PUFA, saturated FA, n-3 FA, and hydroxy and nonmethylene-interrupted FA (P < 0.05) in the TBM compared with the NZGLM. The major FA in the NZGLM were 16:0 (15-17%), 20:5n-3 (14-20%), and 22:6n-3 (11-17%). The same FA dominated lipids in the TBM, although there were significantly higher proportions of 16:0 (P = 0.000) and 22:6 n-3 (P = 0.003) and lower proportions of 20:5n-3 (P = 0.0072) in the TBM. A novel PUFA, 28:8n-3, was detected in both mussels with higher amounts in the TBM, which probably reflects a greater dietary contribution of dinoflagellates for this species. Cholesterol was the dominant sterol in both mussels. Other major sterols included brassicasterol, 22-methylcholesterol, trans-22-dehydrocholesterol, and desmosterol. There were significant differences (P < 0.05) between the NZGLM and TBM for 12 of the 20 sterols measured. Six sterols showed significant site differences for the NZGLM, and 10 for the TBM. The differences in the FA and sterol composition between the two species may be due to the diet of the NZGLM being more diatom-derived and the diet of the TBM having a greater dinoflagellate component.

Brown Norway rats immunized with bovine tubular basement membrane (TBM) antigens develop tubulointerstitial nephritis. The composition of the inflammatory cell infiltrate was characterized in kidney tissue sections and cell suspensions obtained from affected kidneys. Anti-TBM antibody deposition in the kidney began 8 days after immunization and was followed on days 8 to 10 by C3 deposits and infiltration of polymorphonuclear leukocytes (PMN). After day 13, the infiltrate became almost exclusively mononuclear in character. On day 13, the inflammatory mononuclear cells recovered by Ficoll-Hypaque centrifugation contained 10% Ig+ cells (B cells), 60% W3/25+ cells (T helper cells), 9% OX8+ cells (T suppressor cells), 9% esterase+ cells (monocytes/macrophages), 4% renal cells, and 8% other unidentified cells. Monocytes/macrophages were prominent only at the latest stages of the disease. The ratio of W3/25+ to OX8+ cells was higher in the kidney than in the spleen or peripheral blood. The sequential accumulation of T cells and then monocytes/macrophages after an initial antibody, complement, and PMN lesion suggests a role for the T cells (selective prevalence of the helper T cell population over that of suppressor T cells) both as inflammatory cells and in progression and regulation of the subsequent stages of injury.

BACKGROUND

In Africa, tuberculous meningitis (TBM) is an important opportunistic infection in HIV-positive patients. Current diagnostic tools for TBM perform sub-optimally. In particular, the rapid diagnosis of TBM is challenging because smear microscopy has a low yield and PCR is not widely available in resource-poor settings.

METHODS

We evaluated the performance outcome of a novel standardized lipoarabinomannan (LAM) antigen-detection assay, using archived cerebrospinal fluid samples, in 50 African TBM suspects of whom 68% were HIV-positive.

RESULTS

Of the 50 participants 14, 23 and 13 patients had definite, probable and non-TBM, respectively. In the non-TB group there were 5 HIV positive patients who were lost to follow-up and in whom concomitant infection with Mycobacterium tuberculosis could not be definitively excluded. The test sensitivities and specificities were as follows: LAM assay 64% and 69% (cut-point 0.22), smear microscopy 0% and 100% and PCR 93% and 77%, respectively.

CONCLUSIONS

In this preliminary proof-of-concept study, a rapid diagnosis of TBM could be achieved using LAM antigen detection. Although specificity was sub-optimal, the estimates provided here may be unreliable because of a classification bias inherent in the study design where it was not possible to exclude TBM in the presumed non-TBM cases owing to a lack of clinical follow-up. As PCR is largely unavailable, the LAM assay may well prove to be a useful adjunct for the rapid diagnosis of TBM in high HIV-incidence settings. These preliminary results justify further enquiry and prospective studies are now required to definitively establish the place of this technology for the diagnosis of TBM.

BACKGROUND

Current tools for the rapid diagnosis of tuberculous meningitis (TBM) are suboptimal. We evaluated the clinical utility of a quantitative RD-1 IFN-gamma T-cell enzyme-linked immunospot (ELISPOT) assay (T-SPOT.TB), using cerebrospinal fluid cells for the rapid immunodiagnosis of TBM.

OBJECTIVE

To evaluate the diagnostic utility of the RD1 antigen- specific ELISPOT assay for the diagnosis of tuberculous meningitis.

METHODS

The ELISPOT assay was evaluated in 150 patients with suspected TBM who were categorized as definite-TBM, probable-TBM, and non-TBM. Culture or polymerase chain reaction positivity for Mycobacerium tuberculosis served as the reference standard. To determine the diagnostic value of the ELISPOT assay, a clinical prediction rule was derived from baseline clinical and laboratory parameters using a multivariable regression model.

RESULTS

A total of 140 patients (81% HIV-infected; median CD4 count, 160 cells/mm(3)) were included in the final analysis. When comparing the definite-TBM (n = 38) and non-TBM groups (n = 48), the ELISPOT assay (cut point of>> or =228 spot-forming cells per 1 million mononuclear cells) was a useful rule-in test: sensitivity 58% (95% confidence interval [CI], 41-74); specificity 94% (95% CI, 83-99). However, ELISPOT outcomes improved when other rapid tests were concurrently used to exclude bacterial (Gram stain) and cryptococcal meningitis (latex-agglutination test) within the non-TBM group. Using this approach, the ELISPOT assay (cut point of>> or =46 spot-forming cells) was an excellent rule-in test: sensitivity 82% (95% CI, 66-92); specificity 100% (95% CI, 78-100); positive predictive value, 100% (95% CI, 89-100); negative predictive value, 68% (95% CI, 45-86); area under the curve, 0.90. The ELISPOT assay had incremental diagnostic value compared with the clinical prediction rule.

CONCLUSIONS

The RD-1 ELISPOT assay, using cerebrospinal fluid mononuclear cells and in conjunction with other rapid confirmatory tests (Gram stain and cryptococcal latex-agglutination test), is an accurate rapid rule-in test for TBM in a TB and HIV endemic setting.

OBJECTIVE

To examine diagnostic utility of polymerase chain reaction (PCR) on cerebrospinal fluid (CSF) in tuberculous meningitis (TBM).

METHODS

Comparison study.

METHODS

Referral center for tuberculosis diagnosis and treatment in Ho Chi Minh City, Vietnam, and research laboratory in Amsterdam, the Netherlands.

METHODS

One hundred thirty-six consecutive patients, aged 4 months to 85 years, with features compatible with TBM seen during a 12-month period.

METHODS

Clinical examination; cytology; Gram, india ink, and Ziehl-Neelsen staining; culture of CSF for bacteria, mycobacteria, fungi, and viruses; and CSF chloride, protein, and glucose. All these tests were performed in Vietnam. The PCR on CSF was performed in the Netherlands.

RESULTS

Patients were managed in Vietnam without knowledge of PCR results. Based on clinical grounds and the results of initial CSF microscopy, antituberculous treatment was given to 104 patients, 66 of whom had evidence of extraneural tuberculosis. Among the 39 patients with confirmed TBM (ie, positive Ziehl-Neelsen staining or culture or PCR results for Mycobacterium tuberculosis), PCR detected 32 patients (82%), 1 case was proven positive through microscopy and 17 (44%) had positive culture results. There were no false-positive PCR results. In 99 patients with a final diagnosis of confirmed or probable TBM (ie, clinical features of TBM and response to antituberculous treatment), PCR had a sensitivity of 32%; culture, 17% and microscopy, 1%.

CONCLUSIONS

Many patients who respond to treatment for TBM do not have M tuberculosis in the CSF identifiable by microscopy, PCR, or culture. Polymerase chain reaction on CSF is the best method for the laboratory diagnosis of TBM. Polymerase chain reaction is especially useful for the early diagnosis of TBM in those without active extraneural tuberculosis.

HIV-associated tuberculous meningitis (TBM) poses significant diagnostic and therapeutic challenges and carries a dismal prognosis. In this review, we present the clinical features and management of HIV-associated TBM, and compare this to disease in HIV-uninfected individuals. Although the clinical presentation, laboratory findings and radiological features of TBM are similar in HIV-infected and HIV-uninfected patients, some important differences exist. HIV-infected patients present more frequently with extra-meningeal tuberculosis and systemic features of HIV infection. In HIV-associated TBM, clinical course and outcome are influenced by profound immunosuppression at presentation, emphasising the need for earlier diagnosis of HIV infection and initiation of antiretroviral treatment.

BACKGROUND

Acquired tracheobronchomalacia (TBM) can cause central airway collapse in patients with COPD and may worsen airflow obstruction and symptoms. It is usually not known whether central airway malacia contributes to airflow obstruction. This study was undertaken to quantify central airway collapsibility and relate it to expiratory flow limitation in patients with TBM.

METHODS

Eighty patients evaluated for acquired TBM and 4 healthy control subjects were studied with measurements of central airway narrowing derived from bronchoscopic videotapes and simultaneous pressure measurements in the trachea and esophagus. Tracheal narrowing was assessed by a shape index and plotted against the transtracheal pressure to measure collapsibility. Subsequently, airflow and transpulmonary pressure (PL) were measured to identify expiratory flow limitation during quiet breathing and to determine the critical PL required for maximum expiratory flow.

RESULTS

Tracheal collapsibility varied widely among patients. Some had profound tracheal narrowing during quiet breathing, and others showed substantial collapse only during forced exhalation. Of the patients, 15% were not flow limited during quiet breathing, 53% were flow limited throughout exhalation, and 30% were flow limited only during the latter part of the exhalation. Patients with flow limitation at rest showed greater tracheal narrowing than those without (p = 0.009), but the severity of expiratory flow limitation was not closely related to tracheal collapsibility. Twenty-three patients were flow limited during quiet exhalation at PLs that did not cause central airway collapse.

CONCLUSIONS

In TBM, central airway collapse is not closely related to airflow obstruction, and expiratory flow limitation at rest often occurs in peripheral airways without central airway collapse.

Ventriculo-peritoneal (VP) shunting used in the treatment for hydrocephalus is associated with several complications. Mechanical failure of shunt is the commonest complication of all. Visceral/bowel perforation is an unusual but serious complication of VP shunting. This article reports our experience in the management of ten children who had VP Shunt catheter protrusion from anus. This is a retrospective study of ten patients who had VP shunt catheter protrusion from anus, admitted in the department of paediatric surgery between Jan 1996 and Dec 2005. The records of above ten cases were reviewed for their clinical presentation and management, etc. We had performed 398 VP shunt operations in the last 10 years. Two hundred and seventy one (68.09%) VP Shunts were done for congenital hydrocephalus of which 164 were done in infancy/neonatal period and 107 VP shunts were done in the age group of >1-12 years. One hundred and twenty-seven (31.90%) VP shunt operations were done for patients who had hydrocephalus as a complication following tubercular meningitis (TBM). Out of 398 VP shunts, ten patients (2.51%) had protrusion of the distal end of peritoneal catheter from anus without causing/leading to peritonitis. We observed a 08.29% mortality of all VP shunt operations. Protrusion of VP shunt catheter per rectum can occur without producing peritonitis. Formal exploration and localization of entry of VP shunt catheter in bowel is not mandatory. Mini laparotomy and revision of peritoneal part of shunt can be done if there is no shunt infection.

An immunodiagnostic test for the detection of a soluble nonprotein mycobacterial antigen by reverse passive haemagglutination with IgM murine monoclonal antibody was developed. The test was used to analyse the cerebrospinal fluid of 89 patients with tuberculous meningitis (TBM) from India and 127 control subjects from India and the UK. The antigen was demonstrable in 88% of culture-positive and 73% of culture-negative TBM patients. However, it was also detected in 21% of Indian patients with pyogenic meningitis, and in 8% of Indian and 1% of UK control subjects. Antibodies binding to a soluble mycobacterial extract were detected at low titre in 68% of all subjects with TBM and in 37% of Indian cases of pyogenic meningitis. Because patients with TBM had raised levels of the antigen and of antibodies to the antigen, the possible role of immune complexes in the pathogenesis of the disease is briefly discussed.

Epithelial cells from a variety of species and organs form polarized epithelia in culture. When epithelia are grown on a porous surface, such as a millipore filter, transport can be studied using adaptations of standard techniques. In the few years in which cultured epithelia have been studied by transport physiologists, most work has been focused on identification and description of the differentiated transport exhibited by cultured epithelia. Epithelia formed by a continuous line of cells derived from pig kidney (LLC-PK1) exhibit sodium-coupled glucose transport similar to that of the proximal tubule and have vasopressin-sensitive adenylate cyclase that has been studied in great detail. Also of interest are epithelia formed by continuous lines of cells derived from amphibian kidney (A6) and from amphibian urinary bladder (TBM). Each line forms epithelia that have high electrical resistance and amiloride-sensitive sodium transport. Transport is stimulated by aldosterone and by cAMP or hormones that raise cell cAMP levels. In LLC-PK1 and in A6 epithelia, transport and the response to hormones can be manipulated by manipulating the culture conditions. Cultured epithelia have also been used to explore the cell biology of epithelia. Most interesting in this regard are studies of the development and maintenance of epithelial cell polarity. This approach should be especially valuable.