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Graeme Meintjes - One of the best experts on this subject based on the ideXlab platform.
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neutrophil associated central nervous system inflammation in tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2014Co-Authors: Suzaan Marais, Katalin A Wilkinson, Maia Lesosky, Anna K Coussens, Armin Deffur, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme MeintjesAbstract:Background. The immunopathogenesis of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) remains incompletely understood, and we know of only 1 disease site-specific study of the underlying immunology; we recently showed that Mycobacterium tuberculosis culture positivity and increased neutrophils in the cerebrospinal fluid (CSF) of patients with tuberculous meningitis (TBM) are associated with TBM-IRIS. In this study we investigated inflammatory mediators at the disease site in patients with TBM-IRIS. Methods. We performed lumbar puncture at 3–5 time points in human immunodeficiency virus (HIV)–infected patients with TBM (n = 34), including at TBM diagnosis, at initiation of antiretroviral therapy (ART) (day 14), 14 days after ART initiation, at presentation of TBM-IRIS, and 14 days thereafter. We determined the concentrations of 40 mediators in CSF (33 paired with blood) with Luminex or enzyme-linked immunosorbent assays. Findings were compared between patients who developed TBM-IRIS (n = 16) and those who did not (TBM-non-IRIS; n = 18). Results. At TBM diagnosis and 2 weeks after ART initiation, TBM-IRIS was associated with severe, compartmentalized inflammation in the CSF, with elevated concentrations of cytokines, chemokines, neutrophil-associated mediators, and matrix metalloproteinases, compared with TBM-non-IRIS. Patients with TBM-non-IRIS whose CSF cultures were positive for M. tuberculosis at TBM diagnosis (n = 6) showed inflammatory responses similar to those seen in patients with TBM-IRIS at both time points. However, at 2 weeks after ART initiation, S100A8/A9 was significantly increased in patients with TBM-IRIS, compared with patients with TBM-non-IRIS whose cultures were positive at baseline. Conclusions. A high baseline M. tuberculosis antigen load drives an inflammatory response that manifests clinically as TBM-IRIS in most, but not all, patients with TBM. Neutrophils and their mediators, especially S100A8/A9, are closely associated with the central nervous system inflammation that characterizes TBM-IRIS.
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frequency severity and prediction of tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2013Co-Authors: Suzaan Marais, Katalin A Wilkinson, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme Meintjes, Lori E Dodd, Robert J WilkinsonAbstract:Background. Tuberculosis immune reconstitution inflammatory syndrome (IRIS) is a common cause of deterioration in human immunodeficiency virus (HIV)–infected patients receiving tuberculosis treatment after starting antiretroviral therapy (ART). Potentially life-threatening neurological involvement occurs frequently and has been suggested as a reason to defer ART. Methods. We conducted a prospective study of HIV-infected, ART-naive patients with tuberculous meningitis (TBM). At presentation, patients started tuberculosis treatment and prednisone; ART was initiated 2 weeks later. Clinical and laboratory findings were compared between patients who developed TBM-IRIS (TBM-IRIS patients) and those who did not (non-TBM-IRIS patients). A logistic regression model was developed to predict TBM-IRIS. Results. Forty-seven percent (16/34) of TBM patients developed TBM-IRIS, which manifested with severe features of inflammation. At TBM diagnosis, TBM-IRIS patients had higher cerebrospinal fluid (CSF) neutrophil counts compared with non-TBM-IRIS patients (median, 50 vs 3 cells ×106/L, P = .02). Mycobacterium tuberculosis was cultured from CSF of 15 TBM-IRIS patients (94%) compared with 6 non-TBM-IRIS patients (33%) at time of TBM diagnosis; relative risk of developing TBM-IRIS if CSF was Mycobacterium tuberculosis culture positive = 9.3 (95% confidence interval [CI], 1.4–62.2). The combination of high CSF tumor necrosis factor (TNF)-α and low interferon (IFN)-γ at TBM diagnosis predicted TBM-IRIS (area under the curve = 0.91 [95% CI, .53–.99]). Conclusions. TBM-IRIS is a frequent, severe complication of ART in HIV-associated TBM and is characterized by high CSF neutrophil counts and Mycobacterium tuberculosis culture positivity at TBM presentation. The combination of CSF IFN-γ and TNF-α concentrations may predict TBM-IRIS and thereby be a means to individualize patients to early or deferred ART.
Katalin A Wilkinson - One of the best experts on this subject based on the ideXlab platform.
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neutrophil associated central nervous system inflammation in tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2014Co-Authors: Suzaan Marais, Katalin A Wilkinson, Maia Lesosky, Anna K Coussens, Armin Deffur, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme MeintjesAbstract:Background. The immunopathogenesis of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) remains incompletely understood, and we know of only 1 disease site-specific study of the underlying immunology; we recently showed that Mycobacterium tuberculosis culture positivity and increased neutrophils in the cerebrospinal fluid (CSF) of patients with tuberculous meningitis (TBM) are associated with TBM-IRIS. In this study we investigated inflammatory mediators at the disease site in patients with TBM-IRIS. Methods. We performed lumbar puncture at 3–5 time points in human immunodeficiency virus (HIV)–infected patients with TBM (n = 34), including at TBM diagnosis, at initiation of antiretroviral therapy (ART) (day 14), 14 days after ART initiation, at presentation of TBM-IRIS, and 14 days thereafter. We determined the concentrations of 40 mediators in CSF (33 paired with blood) with Luminex or enzyme-linked immunosorbent assays. Findings were compared between patients who developed TBM-IRIS (n = 16) and those who did not (TBM-non-IRIS; n = 18). Results. At TBM diagnosis and 2 weeks after ART initiation, TBM-IRIS was associated with severe, compartmentalized inflammation in the CSF, with elevated concentrations of cytokines, chemokines, neutrophil-associated mediators, and matrix metalloproteinases, compared with TBM-non-IRIS. Patients with TBM-non-IRIS whose CSF cultures were positive for M. tuberculosis at TBM diagnosis (n = 6) showed inflammatory responses similar to those seen in patients with TBM-IRIS at both time points. However, at 2 weeks after ART initiation, S100A8/A9 was significantly increased in patients with TBM-IRIS, compared with patients with TBM-non-IRIS whose cultures were positive at baseline. Conclusions. A high baseline M. tuberculosis antigen load drives an inflammatory response that manifests clinically as TBM-IRIS in most, but not all, patients with TBM. Neutrophils and their mediators, especially S100A8/A9, are closely associated with the central nervous system inflammation that characterizes TBM-IRIS.
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frequency severity and prediction of tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2013Co-Authors: Suzaan Marais, Katalin A Wilkinson, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme Meintjes, Lori E Dodd, Robert J WilkinsonAbstract:Background. Tuberculosis immune reconstitution inflammatory syndrome (IRIS) is a common cause of deterioration in human immunodeficiency virus (HIV)–infected patients receiving tuberculosis treatment after starting antiretroviral therapy (ART). Potentially life-threatening neurological involvement occurs frequently and has been suggested as a reason to defer ART. Methods. We conducted a prospective study of HIV-infected, ART-naive patients with tuberculous meningitis (TBM). At presentation, patients started tuberculosis treatment and prednisone; ART was initiated 2 weeks later. Clinical and laboratory findings were compared between patients who developed TBM-IRIS (TBM-IRIS patients) and those who did not (non-TBM-IRIS patients). A logistic regression model was developed to predict TBM-IRIS. Results. Forty-seven percent (16/34) of TBM patients developed TBM-IRIS, which manifested with severe features of inflammation. At TBM diagnosis, TBM-IRIS patients had higher cerebrospinal fluid (CSF) neutrophil counts compared with non-TBM-IRIS patients (median, 50 vs 3 cells ×106/L, P = .02). Mycobacterium tuberculosis was cultured from CSF of 15 TBM-IRIS patients (94%) compared with 6 non-TBM-IRIS patients (33%) at time of TBM diagnosis; relative risk of developing TBM-IRIS if CSF was Mycobacterium tuberculosis culture positive = 9.3 (95% confidence interval [CI], 1.4–62.2). The combination of high CSF tumor necrosis factor (TNF)-α and low interferon (IFN)-γ at TBM diagnosis predicted TBM-IRIS (area under the curve = 0.91 [95% CI, .53–.99]). Conclusions. TBM-IRIS is a frequent, severe complication of ART in HIV-associated TBM and is characterized by high CSF neutrophil counts and Mycobacterium tuberculosis culture positivity at TBM presentation. The combination of CSF IFN-γ and TNF-α concentrations may predict TBM-IRIS and thereby be a means to individualize patients to early or deferred ART.
Dominique J Pepper - One of the best experts on this subject based on the ideXlab platform.
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neutrophil associated central nervous system inflammation in tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2014Co-Authors: Suzaan Marais, Katalin A Wilkinson, Maia Lesosky, Anna K Coussens, Armin Deffur, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme MeintjesAbstract:Background. The immunopathogenesis of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) remains incompletely understood, and we know of only 1 disease site-specific study of the underlying immunology; we recently showed that Mycobacterium tuberculosis culture positivity and increased neutrophils in the cerebrospinal fluid (CSF) of patients with tuberculous meningitis (TBM) are associated with TBM-IRIS. In this study we investigated inflammatory mediators at the disease site in patients with TBM-IRIS. Methods. We performed lumbar puncture at 3–5 time points in human immunodeficiency virus (HIV)–infected patients with TBM (n = 34), including at TBM diagnosis, at initiation of antiretroviral therapy (ART) (day 14), 14 days after ART initiation, at presentation of TBM-IRIS, and 14 days thereafter. We determined the concentrations of 40 mediators in CSF (33 paired with blood) with Luminex or enzyme-linked immunosorbent assays. Findings were compared between patients who developed TBM-IRIS (n = 16) and those who did not (TBM-non-IRIS; n = 18). Results. At TBM diagnosis and 2 weeks after ART initiation, TBM-IRIS was associated with severe, compartmentalized inflammation in the CSF, with elevated concentrations of cytokines, chemokines, neutrophil-associated mediators, and matrix metalloproteinases, compared with TBM-non-IRIS. Patients with TBM-non-IRIS whose CSF cultures were positive for M. tuberculosis at TBM diagnosis (n = 6) showed inflammatory responses similar to those seen in patients with TBM-IRIS at both time points. However, at 2 weeks after ART initiation, S100A8/A9 was significantly increased in patients with TBM-IRIS, compared with patients with TBM-non-IRIS whose cultures were positive at baseline. Conclusions. A high baseline M. tuberculosis antigen load drives an inflammatory response that manifests clinically as TBM-IRIS in most, but not all, patients with TBM. Neutrophils and their mediators, especially S100A8/A9, are closely associated with the central nervous system inflammation that characterizes TBM-IRIS.
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frequency severity and prediction of tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2013Co-Authors: Suzaan Marais, Katalin A Wilkinson, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme Meintjes, Lori E Dodd, Robert J WilkinsonAbstract:Background. Tuberculosis immune reconstitution inflammatory syndrome (IRIS) is a common cause of deterioration in human immunodeficiency virus (HIV)–infected patients receiving tuberculosis treatment after starting antiretroviral therapy (ART). Potentially life-threatening neurological involvement occurs frequently and has been suggested as a reason to defer ART. Methods. We conducted a prospective study of HIV-infected, ART-naive patients with tuberculous meningitis (TBM). At presentation, patients started tuberculosis treatment and prednisone; ART was initiated 2 weeks later. Clinical and laboratory findings were compared between patients who developed TBM-IRIS (TBM-IRIS patients) and those who did not (non-TBM-IRIS patients). A logistic regression model was developed to predict TBM-IRIS. Results. Forty-seven percent (16/34) of TBM patients developed TBM-IRIS, which manifested with severe features of inflammation. At TBM diagnosis, TBM-IRIS patients had higher cerebrospinal fluid (CSF) neutrophil counts compared with non-TBM-IRIS patients (median, 50 vs 3 cells ×106/L, P = .02). Mycobacterium tuberculosis was cultured from CSF of 15 TBM-IRIS patients (94%) compared with 6 non-TBM-IRIS patients (33%) at time of TBM diagnosis; relative risk of developing TBM-IRIS if CSF was Mycobacterium tuberculosis culture positive = 9.3 (95% confidence interval [CI], 1.4–62.2). The combination of high CSF tumor necrosis factor (TNF)-α and low interferon (IFN)-γ at TBM diagnosis predicted TBM-IRIS (area under the curve = 0.91 [95% CI, .53–.99]). Conclusions. TBM-IRIS is a frequent, severe complication of ART in HIV-associated TBM and is characterized by high CSF neutrophil counts and Mycobacterium tuberculosis culture positivity at TBM presentation. The combination of CSF IFN-γ and TNF-α concentrations may predict TBM-IRIS and thereby be a means to individualize patients to early or deferred ART.
Theodore S Hong - One of the best experts on this subject based on the ideXlab platform.
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irradiation of anatomically defined pelvic subsites and acute hematologic toxicity in anal cancer patients undergoing chemoradiation
Practical radiation oncology, 2016Co-Authors: Brent S Rose, Andrzej Niemierko, Janet E Murphy, Lawrence S Blaszkowsky, Jill N Allen, Lorraine C Drapek, Theodore S Hong, Devarati Mitra, Kyung Wook Ken Jee, Jeffrey W ClarkAbstract:Abstract Purpose Chemoradiation for the treatment of anal cancer is known to cause significant hematologic toxicity (HT). We sought to investigate if radiation dose to specific pelvic subsites is associated with increased HT risk. Methods and materials Forty-five patients with nonmetastatic anal cancer who received definitive chemoradiation with intensity modulated radiation therapy and concurrent mitomycin-C and 5-fluorouracil were studied. Total pelvic bone marrow (TBM) was divided into 3 subsites: lumbosacral bone marrow (LSBM), including the entire sacrum and L5 vertebral body; iliac bone marrow (IBM) extending from the iliac crests to the superior border of the femoral head; and lower pelvic bone marrow, including the pubic bones, ischia, acetabula, and proximal femurs. The primary endpoint was absolute neutrophil count (ANC) nadir during or within 2 weeks of treatment completion. Generalized linear modeling was used to analyze the correlation between the equivalent uniform dose (with an "a" value of 0.5) to the individual pelvic subsites and the various hematologic endpoints. Age, body mass index, sex, baseline blood counts, and immunosuppression were analyzed as potential covariates. Results Mean ± standard deviation ANC nadir was 0.77 × 10 9 /L (±0.66 × 10 9 /L). Grades 3+ and 4+ neutropenia occurred in 71.1% and 44.4% of patients, respectively. In addition to radiation dose to pelvic bone marrow, baseline ANC was the only significant predictor of hematologic toxicity on multivariable analysis and was included in all models. The equivalent uniform doses of TBM, LSBM, and IBM were each significantly associated with neutropenia. The model performance of TBM (adjusted R 2 = 0.226) was similar to both LSBM (adjusted R 2 = 0.206) and IBM (adjusted R 2 = 0.249). Conclusions Radiation doses to TBM, LSBM, and IBM were individually associated with HT, suggesting that sparing just a portion of pelvic bone marrow is insufficient to decrease rates of clinically significant bone marrow suppression.
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irradiation of fdg pet defined active bone marrow subregions and acute hematologic toxicity in anal cancer patients undergoing chemoradiation
International Journal of Radiation Oncology Biology Physics, 2015Co-Authors: Brent S Rose, Kyungwook Jee, Andrzej Niemierko, Janet E Murphy, Lawrence S Blaszkowsky, Jill N Allen, Leslie K Lee, Yingbing Wang, Lorraine C Drapek, Theodore S HongAbstract:Purpose Irradiation of pelvic bone marrow (BM) has been correlated with hematologic toxicity (HT) in patients undergoing chemoradiation for anal cancer. We hypothesized that irradiation of hematologically active bone marrow (ABM) subregions defined by fluorodeoxyglucose (FDG) positron emission tomography (PET) is a principal cause of radiation-associated HT. Methods and Materials The cohort included 45 patients with nonmetastatic anal cancer who underwent FDG-PET imaging prior to definitive chemoradiation with mitomycin-C and 5-fluorouracil. Total bone marrow (TBM) was defined as the external contour of the pelvic bones from the top of lumbar 5 (L5) to the bottom of the ischial tuberosity. Standardized uptake values (SUV) for all voxels within the TBM were quantified and normalized by comparison to normal liver SUV. Subvolumes of the TBM that exhibited the highest and lowest 50% of the SUVs were designated ABM 50 and IBM 50 , respectively. The primary endpoint was the absolute neutrophil count (ANC) nadir during or within 2 weeks of completion of treatment. Multivariate linear modeling was used to analyze the correlation between the equivalent uniform doses (EUD) with an a value of 0.5, 1 (equivalent to mean dose), 3, 7, and 12 to the BM structures and the ANC. Results Mean ± SD ANC nadir was 0.77 × 10 9 /L (±0.66 × 10 9 /L). Grades 3 and 4 ANC toxicity occurred in 26.7% and 44.4% of patients, respectively. The EUD a parameter of 0.5 was optimal for all BM models indicating high radiation sensitivity. EUD of TBM and ABM 50 and IBM 50 were all significantly associated with ANC nadir. However, model performance for ABM 50 was not superior to that of the TBM and IBM 50 models. Conclusions Irradiation of pelvic BM was associated with HT. However, FDG-PET–defined ABM models failed to improve model performance compared to the TBM model.
Suzaan Marais - One of the best experts on this subject based on the ideXlab platform.
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neutrophil associated central nervous system inflammation in tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2014Co-Authors: Suzaan Marais, Katalin A Wilkinson, Maia Lesosky, Anna K Coussens, Armin Deffur, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme MeintjesAbstract:Background. The immunopathogenesis of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) remains incompletely understood, and we know of only 1 disease site-specific study of the underlying immunology; we recently showed that Mycobacterium tuberculosis culture positivity and increased neutrophils in the cerebrospinal fluid (CSF) of patients with tuberculous meningitis (TBM) are associated with TBM-IRIS. In this study we investigated inflammatory mediators at the disease site in patients with TBM-IRIS. Methods. We performed lumbar puncture at 3–5 time points in human immunodeficiency virus (HIV)–infected patients with TBM (n = 34), including at TBM diagnosis, at initiation of antiretroviral therapy (ART) (day 14), 14 days after ART initiation, at presentation of TBM-IRIS, and 14 days thereafter. We determined the concentrations of 40 mediators in CSF (33 paired with blood) with Luminex or enzyme-linked immunosorbent assays. Findings were compared between patients who developed TBM-IRIS (n = 16) and those who did not (TBM-non-IRIS; n = 18). Results. At TBM diagnosis and 2 weeks after ART initiation, TBM-IRIS was associated with severe, compartmentalized inflammation in the CSF, with elevated concentrations of cytokines, chemokines, neutrophil-associated mediators, and matrix metalloproteinases, compared with TBM-non-IRIS. Patients with TBM-non-IRIS whose CSF cultures were positive for M. tuberculosis at TBM diagnosis (n = 6) showed inflammatory responses similar to those seen in patients with TBM-IRIS at both time points. However, at 2 weeks after ART initiation, S100A8/A9 was significantly increased in patients with TBM-IRIS, compared with patients with TBM-non-IRIS whose cultures were positive at baseline. Conclusions. A high baseline M. tuberculosis antigen load drives an inflammatory response that manifests clinically as TBM-IRIS in most, but not all, patients with TBM. Neutrophils and their mediators, especially S100A8/A9, are closely associated with the central nervous system inflammation that characterizes TBM-IRIS.
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frequency severity and prediction of tuberculous meningitis immune reconstitution inflammatory syndrome
Clinical Infectious Diseases, 2013Co-Authors: Suzaan Marais, Katalin A Wilkinson, Dominique J Pepper, Charlotte Schutz, Zahiera Ismail, Graeme Meintjes, Lori E Dodd, Robert J WilkinsonAbstract:Background. Tuberculosis immune reconstitution inflammatory syndrome (IRIS) is a common cause of deterioration in human immunodeficiency virus (HIV)–infected patients receiving tuberculosis treatment after starting antiretroviral therapy (ART). Potentially life-threatening neurological involvement occurs frequently and has been suggested as a reason to defer ART. Methods. We conducted a prospective study of HIV-infected, ART-naive patients with tuberculous meningitis (TBM). At presentation, patients started tuberculosis treatment and prednisone; ART was initiated 2 weeks later. Clinical and laboratory findings were compared between patients who developed TBM-IRIS (TBM-IRIS patients) and those who did not (non-TBM-IRIS patients). A logistic regression model was developed to predict TBM-IRIS. Results. Forty-seven percent (16/34) of TBM patients developed TBM-IRIS, which manifested with severe features of inflammation. At TBM diagnosis, TBM-IRIS patients had higher cerebrospinal fluid (CSF) neutrophil counts compared with non-TBM-IRIS patients (median, 50 vs 3 cells ×106/L, P = .02). Mycobacterium tuberculosis was cultured from CSF of 15 TBM-IRIS patients (94%) compared with 6 non-TBM-IRIS patients (33%) at time of TBM diagnosis; relative risk of developing TBM-IRIS if CSF was Mycobacterium tuberculosis culture positive = 9.3 (95% confidence interval [CI], 1.4–62.2). The combination of high CSF tumor necrosis factor (TNF)-α and low interferon (IFN)-γ at TBM diagnosis predicted TBM-IRIS (area under the curve = 0.91 [95% CI, .53–.99]). Conclusions. TBM-IRIS is a frequent, severe complication of ART in HIV-associated TBM and is characterized by high CSF neutrophil counts and Mycobacterium tuberculosis culture positivity at TBM presentation. The combination of CSF IFN-γ and TNF-α concentrations may predict TBM-IRIS and thereby be a means to individualize patients to early or deferred ART.
