Investigations into HIV-associated tuberculous meningitis

dc.contributor.advisorWilkinson, Robert Jen_ZA
dc.contributor.advisorMeintjes, Graemeen_ZA
dc.contributor.advisorWilkinson, Katalinen_ZA
dc.contributor.authorMarais, Suzaanen_ZA
dc.date.accessioned2014-11-07T09:16:54Z
dc.date.available2014-11-07T09:16:54Z
dc.date.issued2014en_ZA
dc.descriptionIncludes bibliographical references.en_ZA
dc.description.abstract[Background] Tuberculous meningitis (TBM) is a common form of tuberculosis in high TB incidence settings. However, the burden of disease and outcome in affected adults is unknown in Cape Town. The diagnosis of TBM is often challenging, particularly in HIV co-infected patients and no standardized clinical case definition exists. An emerging complication that contributes to poor outcome in HIV-associated TBM is neurological TB immune reconstitution inflammatory syndrome (TB-IRIS). [Methods] A consensus clinical TBM case definition was developed following a TBM meeting that I co-ordinated. I led two observational studies that determined the burden of HIV-associated TBM and neurological TB-IRIS at a district-level hospital in Cape Town. Patients with HIV-associated TBM were prospectively enrolled in a third cohort study to determine the clinical and immunological characteristics of paradoxical TBM-IRIS. [Results] TBM accounted for 57% of meningitis cases over a 6-months period; 88% of these patients were HIV-infected. At six months follow-up, mortality in HIV-associated TBM patients was 48%. Neurological TB-IRIS accounted for 21% of patients who presented with central nervous system (CNS) deterioration during the first year of antiretroviral therapy (ART) over a one-year period. TBM-IRIS developed in 47% of HIV-associated TBM patients and associated with extensive cerebrospinal fluid (CSF) inflammation both at TBM diagnosis and at TBM-IRIS presentation. Patients who did not develop TBM-IRIS, but who were culture-positive for Mycobacterium tuberculosis from CSF at TBM diagnosis, showed an immunological phenotype similar to TBM-IRIS patients; however neutrophils were increased in TBM-IRIS patients compared to culture-positive TBM-non-IRIS patients, both at TBM diagnosis and two weeks after ART initiation. [Conclusions] HIV-associated TBM is a common cause of meningitis with a poor outcome in Cape Town. TBM-IRIS is a frequent complication of ART in HIV-associated TBM patients. CSF Mycobacterium tuberculosis culture positivity drives an inflammatory response that manifests as TBM-IRIS in most, but not all TBM patients. Neutrophils associate closely with the CNS inflammation that characterizes TBM-IRIS. An intensified TB treatment regimen with increased CSF penetration early during TB treatment may lead to improved mycobacterial clearance from the CNS, which may result in improved outcome during TBM treatment and a reduced frequency of TBM-IRIS. We aim to test this hypothesis in future studies.en_ZA
dc.identifier.apacitationMarais, S. (2014). <i>Investigations into HIV-associated tuberculous meningitis</i>. (Thesis). University of Cape Town ,Faculty of Health Sciences ,Department of Medicine. Retrieved from http://hdl.handle.net/11427/9304en_ZA
dc.identifier.chicagocitationMarais, Suzaan. <i>"Investigations into HIV-associated tuberculous meningitis."</i> Thesis., University of Cape Town ,Faculty of Health Sciences ,Department of Medicine, 2014. http://hdl.handle.net/11427/9304en_ZA
dc.identifier.citationMarais, S. 2014. Investigations into HIV-associated tuberculous meningitis. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Marais, Suzaan AB - [Background] Tuberculous meningitis (TBM) is a common form of tuberculosis in high TB incidence settings. However, the burden of disease and outcome in affected adults is unknown in Cape Town. The diagnosis of TBM is often challenging, particularly in HIV co-infected patients and no standardized clinical case definition exists. An emerging complication that contributes to poor outcome in HIV-associated TBM is neurological TB immune reconstitution inflammatory syndrome (TB-IRIS). [Methods] A consensus clinical TBM case definition was developed following a TBM meeting that I co-ordinated. I led two observational studies that determined the burden of HIV-associated TBM and neurological TB-IRIS at a district-level hospital in Cape Town. Patients with HIV-associated TBM were prospectively enrolled in a third cohort study to determine the clinical and immunological characteristics of paradoxical TBM-IRIS. [Results] TBM accounted for 57% of meningitis cases over a 6-months period; 88% of these patients were HIV-infected. At six months follow-up, mortality in HIV-associated TBM patients was 48%. Neurological TB-IRIS accounted for 21% of patients who presented with central nervous system (CNS) deterioration during the first year of antiretroviral therapy (ART) over a one-year period. TBM-IRIS developed in 47% of HIV-associated TBM patients and associated with extensive cerebrospinal fluid (CSF) inflammation both at TBM diagnosis and at TBM-IRIS presentation. Patients who did not develop TBM-IRIS, but who were culture-positive for Mycobacterium tuberculosis from CSF at TBM diagnosis, showed an immunological phenotype similar to TBM-IRIS patients; however neutrophils were increased in TBM-IRIS patients compared to culture-positive TBM-non-IRIS patients, both at TBM diagnosis and two weeks after ART initiation. [Conclusions] HIV-associated TBM is a common cause of meningitis with a poor outcome in Cape Town. TBM-IRIS is a frequent complication of ART in HIV-associated TBM patients. CSF Mycobacterium tuberculosis culture positivity drives an inflammatory response that manifests as TBM-IRIS in most, but not all TBM patients. Neutrophils associate closely with the CNS inflammation that characterizes TBM-IRIS. An intensified TB treatment regimen with increased CSF penetration early during TB treatment may lead to improved mycobacterial clearance from the CNS, which may result in improved outcome during TBM treatment and a reduced frequency of TBM-IRIS. We aim to test this hypothesis in future studies. DA - 2014 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2014 T1 - Investigations into HIV-associated tuberculous meningitis TI - Investigations into HIV-associated tuberculous meningitis UR - http://hdl.handle.net/11427/9304 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/9304
dc.identifier.vancouvercitationMarais S. Investigations into HIV-associated tuberculous meningitis. [Thesis]. University of Cape Town ,Faculty of Health Sciences ,Department of Medicine, 2014 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/9304en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDepartment of Medicineen_ZA
dc.publisher.facultyFaculty of Health Sciencesen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.titleInvestigations into HIV-associated tuberculous meningitisen_ZA
dc.typeDoctoral Thesis
dc.type.qualificationlevelDoctoral
dc.type.qualificationnamePhDen_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
thesis_hsf_2014_marais_s.pdf
Size:
3.66 MB
Format:
Adobe Portable Document Format
Description:
Collections