Advanced search    

Search: authors:"Mark P. Nicol"

19 papers found.
Use AND, OR, NOT, +word, -word, "long phrase", (parentheses) to fine-tune your search.

A clinical scoring system to prioritise investigation for tuberculosis among adults attending HIV clinics in South Africa

Background The World Health Organization (WHO) recommendation for regular tuberculosis (TB) screening of HIV-positive individuals with Xpert MTB/RIF as the first diagnostic test has major resource implications. Objective To develop a diagnostic prediction model for TB, for symptomatic adults attending for routine HIV care, to prioritise TB investigation. Design Cohort study...

Childhood tuberculosis is associated with decreased abundance of T cell gene transcripts and impaired T cell function

acquisition: Michael Levin. Investigation: Cheryl Hemingway, Suzanne T. Anderson, Victoria J. Wright, Beate Kampmann, Johan Schoeman, Sandra Pienaar, Mark P. Nicol, Michael J. Griffiths, Simon J. Waddell ... . Methodology: Cheryl Hemingway, Maurice Berk, Suzanne T. Anderson, Shea Hamilton, Hariklia Eleftherohorinou, Myrsini Kaforou, Greg M. Goldgof, Katy Hickman, Mark P. Nicol, Michael J. Griffiths, Simon J. Waddell

Diagnostic Accuracy of Lateral Flow Urine LAM Assay for TB Screening of Adults with Advanced Immunosuppression Attending Routine HIV Care in South Africa

Background We assessed the diagnostic accuracy of Determine TB-LAM (LF-LAM) to screen for tuberculosis among ambulatory adults established in HIV care in South Africa. Methods A systematic sample of adults attending for HIV care, regardless of symptomatology, were enrolled in the XPHACTOR study, which tested a novel algorithm for prioritising investigation with Xpert MTB/RIF. In...

Comparison of a Real-Time Multiplex PCR and Sequetyping Assay for Pneumococcal Serotyping

Background Pneumococcal serotype identification is essential to monitor pneumococcal vaccine effectiveness and serotype replacement. Serotyping by conventional serological methods are costly, labour-intensive, and require significant technical expertise. We compared two different molecular methods to serotype pneumococci isolated from the nasopharynx of South African infants...

Detection of Streptococcus pneumoniae from Different Types of Nasopharyngeal Swabs in Children

Interests: Prof. Heather J. Zar and Prof. Mark P. Nicol are members of the PLOS ONE Editorial Board. This does not alter the authors adherence to all the PLOS ONE policies on sharing data and materials

Impact of Xpert MTB/RIF for TB Diagnosis in a Primary Care Clinic with High TB and HIV Prevalence in South Africa: A Pragmatic Randomised Trial

Helen Cox and colleagues investigate the impact Xpert MTB/RIF for diagnosing patients with presumptive tuberculosis in a large primary care clinic in Khayelitsha, Cape Town. Please see later in the article for the Editors' Summary

Advances in the Diagnosis of Pulmonary Tuberculosis in HIV-Infected and HIV-Uninfected Children

Tom G. Connell 0 Heather J. Zar 0 Mark P. Nicol () 0 0 of Clinical Laboratory Sciences, Institute for Infectious Diseases and Molecular Medicine, Faculty of Health Sciences, National Health

Determine TB-LAM lateral flow urine antigen assay for HIV-associated tuberculosis: recommendations on the design and reporting of clinical studies

Detection of the Mycobacterium tuberculosis cell wall antigen lipoarabinomannan (LAM) in urine permits diagnoses of tuberculosis (TB) to be made in HIV-infected patients with advanced immunodeficiency. This can be achieved at the point-of-care within just 30 minutes using the Determine TB-LAM, which is a commercially available, lateral-flow urine ‘strip test’ assay. The assay has...

Xpert MTB/RIF Testing of Stool Samples for the Diagnosis of Pulmonary Tuberculosis in Children

In a pilot accuracy study, stool Xpert testing from 115 children with suspected pulmonary tuberculosis (PTB) detected 8/17 (47%) culture-confirmed tuberculosis cases, including 4/5 (80%) HIV-infected and 4/12 (33%) HIV-uninfected children. Sputum Xpert detected 11/17 (65%) cases. Stool holds promise for PTB diagnosis in HIV-infected children.

Impact of a novel molecular TB diagnostic system in patients at high risk of TB mortality in rural South Africa (Uchwepheshe): study protocol for a cluster randomised trial

Background Tuberculosis control in sub-Saharan Africa has long been hampered by poor diagnostics and weak health systems. New molecular diagnostics, such as the Xpert® MTB/RIF assay, have the potential to improve patient outcomes. We present a cluster randomised trial designed to evaluate whether the positioning of this diagnostic system within the health system has an impact on...

Modern Lineages of Mycobacterium tuberculosis Exhibit Lineage-Specific Patterns of Growth and Cytokine Induction in Human Monocyte-Derived Macrophages

Background Strains of Mycobacterium tuberculosis vary in virulence. Strains that have caused outbreaks in the United States and United Kingdom have been shown to subvert the innate immune response as a potential immune evasion mechanism. There is, however, little information available as to whether these patterns of immune subversion are features of individual strains or...

Outbreak of Multi-Drug Resistant Pseudomonas aeruginosa Bloodstream Infection in the Haematology Unit of a South African Academic Hospital

Lazarus Kuonza Vida Morris Heather Engelbrecht Mark P. Nicol Colleen Bamford Pierre Cornelis, Vrije Universiteit Brussel, Belgium Objective: To describe an outbreak of multi-resistant Pseudomonas

Rapid Molecular Diagnosis of Pulmonary Tuberculosis in Children Using Nasopharyngeal Specimens

Background. A rapid diagnosis of pediatric pulmonary tuberculosis (PTB) using Xpert MTB/RIF (Mycobacterium tuberculosis/rifampicin) automated testing on induced sputum (IS) is possible, but the capacity for performing IS is limited. The diagnosis using a nasopharyngeal aspirate (NPA), which can be non-invasively obtained, is desirable. Methods. Paired specimens (NPA and IS) were...

Screening for HIV-Associated Tuberculosis and Rifampicin Resistance before Antiretroviral Therapy Using the Xpert MTB/RIF Assay: A Prospective Study

. Brooks Katharina Kranzer Mark P. Nicol Andrew Whitelaw Monica Vogt Linda-Gail Bekker Robin Wood Madhukar Pai, McGill University, Canada Background: The World Health Organization has endorsed the Xpert MTB

Rapid Diagnosis of Tuberculosis with the Xpert MTB/RIF Assay in High Burden Countries: A Cost-Effectiveness Analysis

Davis Andrew Whitelaw Mark P. Nicol Maria Tarcela Gler Anar Khaliqov Carlos Zamudio Mark D. Perkins Catharina C. Boehme Frank Cobelens Douglas Wilson, Edendale Hospital, South Africa Background: Xpert

Reversion and conversion of Mycobacterium tuberculosis IFN-γ ELISpot results during anti-tuberculous treatment in HIV-infected children

Background Recent interest has focused on the potential use of serial interferon gamma (IFN-γ) release assay (IGRA) measurements to assess the response to anti-tuberculous (TB) treatment. The kinetics of IFN-γ responses to Mycobacterium tuberculosis (MTB) antigens in HIV-infected children during treatment have not however been previously investigated. Methods IFN-γ responses to...

Failure to Control Growth of Mycobacteria in Blood from Children Infected with Human Immunodeficiency Virus and Its Relationship to T Cell Function

The mechanisms of protective immunity to tuberculosis remain poorly understood in humans. A whole-blood infection model that employs a luminescent readout was used to analyze the role of T cells in control of mycobacterial infection. Control of mycobacterial growth in blood from healthy tuberculin-positive individuals was shown to be mediated predominantly by CD4+ T cells...