Thalidomide Use for Complicated Central Nervous System Tuberculosis in Children: Insights From an Observational Cohort.

BACKGROUND: Much of the neurological sequelae of central nervous system (CNS) tuberculosis (TB) is due to an excessive cytokine-driven host-inflammatory response. Adjunctive corticosteroids, which reduce cytokine production and thus dampen the inflammation, improve overall survival but do not prevent morbidity. This has prompted investigation of more targeted immunomodulatory agents, including thalidomide. METHODS: We describe a retrospective cohort of 38 children consecutively treated with adjunctive thalidomide for CNS TB-related complications over a 10-year period. RESULTS: The most common presenting symptom was focal motor deficit (n = 16), followed by cranial nerve palsies and cerebellar dysfunction. Three of the 38 children presented with large dural-based lesions, manifesting as epilepsia partialis continua (EPC), 4 presented with blindness secondary to optochiasmatic arachnoiditis, and 2 children developed paraplegia due to spinal cord TB mass lesions. Duration of adjunctive thalidomide therapy (3-5 mg/kg/day) varied according to complication type. In children compromised by TB mass lesions, the median treatment duration was 3.9 months (interquartile range [IQR], 2.0-5.0 months), whereas in children with optic neuritis it was 2.0 months (IQR, 1.3-7.3 months) and in EPC it was 1.0 months (IQR, 1-2.5 months). Satisfactory clinical and radiological response was observed in 37 of the children. None of the children experienced rashes, hepatitis, or hematologic derangements or complained of leg cramps. CONCLUSIONS: This study is the largest cohort of adult or pediatric patients treated with adjunctive thalidomide for CNS TB-related complications. The drug has proved to be safe and well tolerated and appears to be clinically efficacious. The potential role of thalidomide or analogues in the treatment of other tuberculous meningitis-related complications requires further exploration.

Standardized Methods for Enhanced Quality and Comparability of Tuberculous Meningitis Studies.

Tuberculous meningitis (TBM) remains a major cause of death and disability in tuberculosis-endemic areas, especially in young children and immunocompromised adults. Research aimed at improving outcomes is hampered by poor standardization, which limits study comparison and the generalizability of results. We propose standardized methods for the conduct of TBM clinical research that were drafted at an international tuberculous meningitis research meeting organized by the Oxford University Clinical Research Unit in Vietnam. We propose a core dataset including demographic and clinical information to be collected at study enrollment, important aspects related to patient management and monitoring, and standardized reporting of patient outcomes. The criteria proposed for the conduct of observational and intervention TBM studies should improve the quality of future research outputs, can facilitate multicenter studies and meta-analyses of pooled data, and could provide the foundation for a global TBM data repository.

Host immune response to tuberculous meningitis.

BACKGROUND: Tuberculous meningitis (TBM) is a severe complication of tuberculosis predominantly affecting young children. Early treatment is vital to prevent morbidity and mortality, emphasizing the importance of early diagnosis. The lack of sensitive methods for early diagnosis is the most common cause of delay. Attempts have been made to develop simplified tests for tuberculosis, but their diagnostic power remains poor. The clinical picture of TBM is mainly driven by the host's immune response to Mycobacterium tuberculosis; therefore, identification of disease-specific biomarkers may have diagnostic and therapeutic value and improve our understanding of its pathogenesis. METHODS: We investigated disease-specific biomarkers of childhood TBM in a cohort of children aged 3 months-13 years with symptoms and signs suggestive of meningitis. Cerebrospinal fluid (CSF) and serum from 56 patients with and 55 patients without TBM were assessed for 28 soluble mediators. RESULTS: Unsupervised hierarchical clustering analysis revealed a disease-specific pattern of biomarkers for TBM relative to other types of meningitis. A biomarker-based diagnostic prediction model for childhood TBM based on CSF concentrations of interleukin 13 (cutoff value, 37.26 pg/mL), vascular endothelial growth factor (cutoff value, 42.92 pg/mL), and cathelicidin LL-37 (cutoff value, 3221.01 pg/mL) is presented with a sensitivity of 0.52 and a specificity of 0.95. CONCLUSIONS: These data highlight the potential of biosignatures in the host's CSF for diagnostic applications and for improving our understanding of the pathogenesis of TBM to discover strategies to prevent immunopathological sequelae.

Uniform research case definition criteria differentiate tuberculous and bacterial meningitis in children.

BACKGROUND: Tuberculous meningitis (TBM) research is hampered by low numbers of microbiologically confirmed TBM cases and the fact that they may represent a select part of the disease spectrum. A uniform TBM research case definition was developed to address these limitations, but its ability to differentiate TBM from bacterial meningitis has not been evaluated. METHODS: We assessed all children treated for TBM from 1985 to 2005 at Tygerberg Children's Hospital, Cape Town, South Africa. For comparative purposes, a group of children with culture-confirmed bacterial meningitis, diagnosed between 2003 and 2009, was identified from the National Health Laboratory Service database. The performance of the proposed case definition was evaluated in culture-confirmed TBM and bacterial meningitis cases. RESULTS: Of 554 children treated for TBM, 66 (11.9%) were classified as "definite TBM," 408 (73.6%) as "probable TBM," and 72 (13.0%) as "possible TBM." "Probable TBM" criteria identified culture-confirmed TBM with a sensitivity of 86% and specificity of 100%; sensitivity was increased but specificity reduced when using "possible TBM" criteria (sensitivity 100%, specificity 56%). CONCLUSIONS: "Probable TBM" criteria accurately differentiated TBM from bacterial meningitis and could be considered for use in clinical trials; reduced sensitivity in children with early TBM (stage 1 disease) remains a concern.

The value of transcranial Doppler imaging in children with tuberculous meningitis.

PURPOSE: Transcranial Doppler imaging (TCDI) is potentially a valuable investigational tool in children with tuberculous meningitis (TBM), a condition often complicated by pathology relevant to Doppler imaging such as raised intracranial pressure (ICP) and cerebral vasculopathies. METHODS: Serial TCDI was performed on 20 TBM children with the aim of investigating cerebrovascular haemodynamics and the relationship between pulsatility index (PI) and ICP. RESULTS: We observed a poor correlation between ICP and PI in children with communicating hydrocephalus (p = 0.72). No decline in PI was noted following 7 days of medical therapy for communicating hydrocephalus (p = 0.78) despite a concomitant decline in ICP. Conversely, a decline in PI was noted in all four children with non-communicating hydrocephalus who underwent cerebrospinal fluid diversion. High blood flow velocities (BFV) in all the basal cerebral arteries were observed in 14 children (70 %). The high BFV persisted for 7 days suggesting stenosis due to vasculitis rather than functional vasospasm. Complete middle cerebral artery (MCA) occlusion, subnormal mean MCA velocities (<40 cm/s) and PIs (<0.4) correlated with radiologically proven large cerebral infarcts. CONCLUSIONS: TCDI-derived PI is not a reliable indicator of raised ICP in children with tuberculous hydrocephalus. This may be attributed to individual variation of tuberculous vascular disease, possibly compromising cerebral vascular compliance and resistance. Basal artery stenosis secondary to vasculitis is observed during the acute stage of TBM in the majority of children.

Tuberculous meningitis: barriers to adherence in home treatment of children and caretaker perceptions.

INTRODUCTION: In-hospital treatment of children with tuberculous meningitis (TBM) is not a feasible option in many resource-poor countries. Home-based treatment has shown to be a viable alternative. Adherence is an important factor determining success of treatment. OBJECTIVE: Identify possible barriers to adherence of home-based treatment and caretaker perception of the disease. METHOD: A qualitative study consisting of 11 in-depth semi-structured interviews was performed based on principles of the health belief model. RESULTS: Barriers of adherence identified include poor understanding of the disease and transmission route, difficulty with medication administration and side effects, lack of access to the health-care facility, long waiting times and hidden costs of transportation. Caretakers showed good appreciation of the adverse effects of noncompliance and benefits obtained from taking treatment in the home environment. CONCLUSION: Improved doctor-patient communication, information brochures, structural changes to hospital settings, provision of financial and peer support all contribute to optimal TBM home-based treatment.

The use of thalidomide to treat children with tuberculosis meningitis: A review.

Much of the morbidity and mortality caused by tuberculous meningitis (TBM) is mediated by a dysregulated immune response. Effective host-directed therapy is therefore critical to improve survival and clinical outcomes. Currently only one host-directed therapy (HDT), corticosteroids, is proven to improve mortality. However, there is no evidence that corticosteroids reduce morbidity and the mechanism of action for mortality reduction is uncertain. Further, it has no proven benefit in HIV co-infected individuals. One promising host-directed therapy approach is to restrict the immunopathology arising from tumour necrosis factor (TNF)-α excess is via TNF-α inhibitors. There are accumulating data on the role of thalidomide, anti-TNF-α monoclonal antibodies (infliximab, adalimumab) and the soluble TNF-α receptor (etanercept) in TBM treatment. Thalidomide was developed nearly seventy years ago and has been a highly controversial drug. Birth defects and toxic adverse effects have limited its use but an improved understanding of its immunological mechanism of action suggest that it may have a crucial role in regulating the destructive host response seen in inflammatory conditions such as TBM. Observational studies at our institution found low dosage adjunctive thalidomide safe in treating tuberculous mass lesions and blindness related to optochiasmatic arachnoiditis, with good clinical and radiological response. In this review, we discuss possible mechanisms of action for thalidomide, based on our clinico-radiologic experience and post-mortem histopathological work. We also propose a rationale for its use in the treatment of certain TBM-related complications.

Management of intracranial tuberculous mass lesions: how long should we treat for?

Tuberculous intracranial mass lesions are common in settings with high tuberculosis (TB) incidence and HIV prevalence. The diagnosis of such lesions, which include tuberculoma and tuberculous abscesses, is often presumptive and based on radiological features, supportive evidence of TB elsewhere and response to TB treatment. However, the treatment response is unpredictable, with lesions frequently enlarging paradoxically or persisting for many years despite appropriate TB treatment and corticosteroid therapy. Most international guidelines recommend a 9-12 month course of TB treatment for central nervous system TB when the infecting Mycobacterium tuberculosis ( M.tb) strain is sensitive to first-line drugs. However, there is variation in opinion and practice with respect to the duration of TB treatment in patients with tuberculomas or tuberculous abscesses. A major reason for this is the lack of prospective clinical trial evidence. Some experts suggest continuing treatment until radiological resolution of enhancing lesions has been achieved, but this may unnecessarily expose patients to prolonged periods of potentially toxic drugs. It is currently unknown whether persistent radiological enhancement of intracranial tuberculomas after 9-12 months of treatment represents active disease, inflammatory response in a sterilized lesion or merely revascularization. The consequences of stopping TB treatment prior to resolution of lesional enhancement have rarely been explored. These important issues were discussed at the 3 rd International Tuberculous Meningitis Consortium meeting. Most clinicians were of the opinion that continued enhancement does not necessarily represent treatment failure and that prolonged TB therapy was not warranted in patients presumably infected with M.tb strains susceptible to first-line drugs. In this manuscript we highlight current medical treatment practices, benefits and disadvantages of different TB treatment durations and the need for evidence-based guidelines regarding the treatment duration of patients with intracranial tuberculous mass lesions.

Absence of an association between Mycobacterium tuberculosis genotype and clinical features in children with tuberculous meningitis.

OBJECTIVES: Animal studies point to increased virulence of certain mycobacterial strains, notably those of the Beijing genotype. There are limited data on mycobacterial genotypic diversity in children with tuberculous meningitis (TBM). We investigated mycobacterial genotypic diversity in children with TBM and analyzed the relationship among genotype, clinical presentation and outcome. PATIENTS AND METHODS: Data were extracted from an ongoing prospective study on children with confirmed TBM from 1992 through 2003 at a referral hospital in the Western Cape Province, South Africa. Mycobacterial isolates were genotyped by standardized restriction fragment length polymorphism methodology. Clinical data at diagnosis, inflammatory progression during the first month of antituberculosis therapy and neurologic outcomes after 6 months of therapy were analyzed according to the principal genetic group of the strain and the presence of the Beijing strain, respectively. RESULTS: Fifty-nine children were included (median age at diagnosis, 23 months); 37 presented with stage II and 22 with stage III presented with TBM. At completion of antituberculosis therapy, 6 children were neurologically normal, 22 were moderately neurologically impaired, 23 were severely neurologically impaired and 6 children died; detailed outcomes were not available in 2 children. All 3 principal genetic groups were represented (group 1, 27.1%; group 2, 59.3%; group 3, 13.6%); the most prevalent strains were of the Beijing genotype (family 29; 25.4%), followed by family 28 (10.2%) and family 11 (8.5%). Predictors of poor neurologic outcome included advanced disease at diagnosis and male gender. There was no association between the principal genetic group of the strain or the presence of the Beijing genotype, and clinical presentation or outcome. CONCLUSIONS: We found no association between Mycobacterium tuberculosis genotypes and clinical presentation or outcome.

Comparison of diagnostic criteria of tuberculous meningitis in human immunodeficiency virus-infected and uninfected children.

INTRODUCTION: Tuberculous (TB) meningitis is sometimes difficult to diagnose in young children. The decision to start anti-TB treatment of TB meningitis is usually made on clinical grounds and results of special investigations, such as cerebrospinal fluid examination and cranial computerized tomography (CT), because bacteriologic yield is low and the results delayed. AIM: To determine whether the clinical, laboratory, and radiologic criteria used in the diagnosis of TB meningitis in human immunodeficiency virus (HIV)-uninfected children apply to HIV-infected children. METHODS: Retrospective, case-control study. Clinical, laboratory, and radiologic features of TB meningitis were compared in 34 HIV-infected and 56 HIV-uninfected patients matched for age and stage of TB meningitis. RESULTS: All clinical differences found between the 2 groups at admission were related to the underlying HIV disease. Neurologic presentation and cerebrospinal fluid findings at admission did not differ significantly between the 2 groups. Significantly more HIV-infected than HIV-uninfected children had evidence of TB on chest radiography. The classic CT signs of TB meningitis (obstructive hydrocephalus and basal enhancement) were significantly less prominent in the HIV-infected group (P < 005). CONCLUSION: The diagnostic criteria for clinical diagnosis of TB meningitis apply to HIV-infected children. However, cranial CT findings in this group may be misleading and delay the diagnosis of TB meningitis.

Brainstem tuberculoma presenting as eight-and-a-half syndrome.

We present a case of a young child who developed eight-and-a-half syndrome following a pontine tuberculoma, an unusual complication of central nervous system tuberculosis not previously described in an immunocompetent child. The combination of clinical findings allowed for precise localization of the lesion whilst magnetic resonance T1 weighted imaging with contrast provided valuable etiological information. We also discuss the management and outcome of the case.

Intractable intracranial tuberculous infection responsive to thalidomide: report of four cases.

Paradoxical enlargement and development of new intracranial tuberculomas and tuberculous brain abscesses on adequate antituberculosis treatment are well recognized and supposedly cytokine mediated. These lesions are often unresponsive to conventional antituberculosis treatment, corticosteroids, and surgery. We therefore assessed the effect of adjunctive thalidomide, a tumor necrosis factor alpha-modulating drug, in intractable intracranial tuberculosis that did not respond to standard medical and surgical therapy. Four consecutive children (three children with bacteriologic proof and one child with clinical evidence of intracranial tuberculosis) were studied. Three patients each had a giant tuberculous abscess, and the fourth had chronic basal arachnoiditis with progressive loss of vision. Three of the four patients had relentless neurologic deterioration, and all showed disease progression on neuroimaging despite full medical and appropriate surgical treatment. Marked clinical and neuroradiologic improvement occurred after thalidomide was added to the antituberculosis treatment regimen of these four patients. Adjunctive thalidomide might have a role in the management of intractable intracranial tuberculosis and needs further investigation in this regard.

Clinicoradiologic response of neurologic tuberculous mass lesions in children treated with thalidomide.

Neurologic tuberculous pseudoabscesses that clinically progress despite conventional antituberculosis therapy may be responsive to adjuvant thalidomide, a potent tumor necrosis factor-α inhibitor. In this study, the addition of thalidomide provided substantial clinical benefit in the majority of patients, and magnetic resonance imaging evolution of lesions from early-stage "T2 bright" with edema to "T2 black" represented a marker of cure.

Vascular endothelial growth factor and blood-brain barrier disruption in tuberculous meningitis.

BACKGROUND: Tuberculous meningitis (TBM) is characterized by disruption of the blood-brain barrier (BBB), cerebral edema and increased intracranial pressure (ICP). Vascular endothelial growth factor (VEGF) is a potent vascular permeability factor and a mediator of brain edema. AIMS: To investigate whether in children with TBM disruption of the BBB relates to VEGF production and to assess the effect of corticosteroids on Mycobacterium tuberculosis-induced VEGF production by mononuclear leukocytes. METHODS: Blood and CSF samples were collected from 26 children with stage 2-3 TBM and 20 controls. All patients received antituberculous and adjuvant corticosteroid therapy. Children were evaluated by ICP recording, computerized tomography scanning and outcome assessment at 6 months follow-up. BBB disruption was quantified by cerebrospinal fluid (CSF)-serum albumin ratios. VEGF concentrations were measured by enzyme-linked immunosorbent assay. In vitro human monocytic THP-1 cells were stimulated with M. tuberculosis sonicate or culture supernatant, and VEGF production was measured in the presence or absence of corticosteroids. RESULTS: CSF VEGF concentrations were significantly higher in TBM patients than in the controls and correlated with mononuclear cell counts (r = 0.64; P = 0.001) and CSF-serum albumin ratio (r = 0.49; P = 0.015). CSF VEGF did not significantly correlate with elevated ICP. In vitro induction of VEGF production by M. tuberculosis sonicate or culture supernatant could be completely abrogated by corticosteroid treatment. CONCLUSIONS: Inflammatory cells secrete VEGF during TBM. CSF VEGF correlates with BBB disruption. Inhibition of VEGF may explain part of the clinical effect of adjuvant corticosteroid therapy in TBM.

Distinguishing PANDAS from Sydenham's chorea: case report and review of the literature.

Children with Sydenham's chorea and PANDAS (Pediatric autoimmune neuropsychiatric disorders associated with streptococcal throat infections) share an array of neuropsychiatric symptoms and distinguishing one from the other, especially at onset can prove challenging. It is, however, important to distinguish between these two post-streptococcal disorders since their response to therapy differs. Children with Sydenham's chorea require long-term benzathine penicillin prophylaxis to reduce the risk of rheumatic heart disease. In contrast, the efficacy of penicillin prophylaxis in preventing tic or obsessive-compulsive symptom exacerbations in children with PANDAS remains doubtful. Immunomodulatory therapies such as plasma exchange and intravenous immunoglobulin have shown to reduce neuropsychiatric symptom severity in children with PANDAS. Tonsillectomy may also represent an effective treatment option in children severely affected by PANDAS. We present this case to demonstrate the pitfalls in differentiating between these two closely associated conditions in a developing country where the prevalence of rheumatic fever is high.

Adjunctive thalidomide therapy for childhood tuberculous meningitis: results of a randomized study.

Childhood tuberculous meningitis is associated with serious long-term sequelae, including mental retardation, behavior disturbances, and motor handicap. Brain damage in tuberculous meningitis results from a cytokine-mediated inflammatory response, which causes vasculitis and obstructive hydrocephalus. Thalidomide, a potent tumor necrosis factor alpha inhibitor, was well tolerated and possibly showed some clinical benefit in children with tuberculous meningitis during a pilot study. The purpose of the present study was to assess the effect of adjunctive thalidomide in addition to standard antituberculosis and corticosteroid therapy on the outcome of tuberculous meningitis. Thalidomide (24 mg/kg/day orally) or placebo was administered in a double-blind randomized fashion for 1 month to patients with stage 2 or 3 tuberculous meningitis. The study was terminated early because all adverse events and deaths occurred in one arm of the study (thalidomide group). Thirty of the 47 children enrolled received adjunctive thalidomide, of whom 6 (20%) developed a skin rash, 8 (26%) hepatitis, and 2 (6%) neutropenia or thrombocytopenia. Four deaths (13%) occurred in patients with very severe neurologic compromise at baseline; two deaths were associated with a rash. Motor outcome after 6 months of antituberculosis therapy was similar in the two groups, even though the thalidomide group showed greater neurologic compromise on admission. In addition, the mean IQ of the two treatment groups did not differ significantly (mean IQ thalidomide group 57.8 versus mean IQ control group 67.5; P = .16). These results do not support the use of adjunctive high-dose thalidomide therapy in the treatment of tuberculous meningitis.

Short intensified treatment in children with drug-susceptible tuberculous meningitis.

BACKGROUND: The World Health Organization recommends 12-month treatment (2RHZE/10RH) for children with tuberculous meningitis (TBM). Studies evaluating length of antituberculous treatment for TBM report similar completion and relapse rates comparing 6-month treatment with 12-month treatment. METHODS: A prospective evaluation to determine whether short-course intensified treatment (6 RHZEth for HIV-infected and 9RHZEth for HIV-infected) is sufficient and safe in children with drug-susceptible TBM. RESULTS: Of 184 children with TBM, median age 58 months and 90 (49%) male, 98 children (53%) presented at stage II TBM, 64 (35%) at stage III TBM and only 22 (12%) at stage I TBM. Ninety (49%) children were treated at home after the first month of therapy; all others received their full treatment in hospital. The HIV prevalence was 14% (22/155 children tested). Anti-TB drug-induced hepatotoxicity occurred in 5% (8 of 143 children tested), all tested negative for viral hepatitis; in all 8 cases, the original regimen was restarted without recurrence. After treatment completion, 147 (80%) children had a good outcome, 7 (3.8%) died. There was no difference in outcome between HIV-infected and HIV-uninfected children who completed treatment (P = 0.986) nor between TBM-hydrocephalic children who were medically treated or shunted (P = 0.166). CONCLUSION: Short intensified treatment is safe and effective in both HIV-infected and HIV-uninfected children with drug-susceptible TBM.

Commercial nucleic acid amplification tests in tuberculous meningitis--a meta-analysis.

Although nucleic acid amplification tests (NAATs) promise a rapid, definitive diagnosis of tuberculous meningitis, the performance of first-generation NAATs was suboptimal and variable. We conducted a meta-analysis of studies published between 2003 and 2013, using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool to evaluate methodological quality. The diagnostic accuracy of newer commercial NAATs was assessed. Pooled estimates of diagnostic accuracy for commercial NAATs measured against a cerebrospinal fluid Mycobacterium tuberculosis culture-positive gold standard were sensitivity 0.64, specificity 0.98, and diagnostic odds ratio 64.0. Heterogeneity was limited; P value = 0.147 and I(2) = 33.85%. The Xpert MTB/RIF® test was evaluated in 1 retrospective study and 4 prospective studies, with pooled sensitivity 0.70 and specificity 0.97. The QUADAS-2 tool revealed low risk of bias, as well as low concerns regarding applicability. Heterogeneity was pronounced among studies of in-house tests. Commercial NAATs proved to be highly specific with greatly reduced heterogeneity compared to in-house tests. Sub-optimal sensitivity remains a limitation.

Neurological manifestations of TB-IRIS: a report of 4 children.

INTRODUCTION: Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is a potentially life-threatening complication in HIV infected children with tuberculosis (TB) of the central nervous system. HIV-associated TB-IRIS has not been previously described in children with neurotuberculosis. OBJECTIVE: To describe the neurological and neuro-radiological features of 4 consecutive cases of TB-IRIS in children with neurotuberculosis and to discuss possible management strategies. RESULTS: Three patients treated for tuberculosis of the central nervous system experienced paradoxical worsening of neurological symptoms when combination antiretroviral therapy (cART) was initiated. Intracranial tuberculomas were unmasked in the 4th patient. All patients developed new neurological signs within 10 days of cART initiation. Neurological symptoms and signs included headache, seizures, meningeal irritation, decreased level of consciousness, ataxia and focal motor deficit. Interventions included the temporary discontinuation of cART and the use of corticosteroids in all patients. Three patients received thalidomide and 1 chloroquine and mycophenolate mofetil. One patient died and the others experienced prolonged hospitalization. CONCLUSION: TB-IRIS should be considered when new neurological signs develop shortly after initiation of cART in children. There is little data to guide the timing of initiation of cART and the management of complications in children.