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Updated: Feb 16, 2026
23:06
The MODS method for diagnosis of tuberculosis and multidrug resistant tuberculosis
Published on: August 11, 2008
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Risk factors for extensive drug resistance in multidrug-resistant tuberculosis cases: a case-case study.
L Guglielmetti1, N Veziris1, A Aubry1
1Sorbonne University, Faculté de Médecine Pierre et Marie Curie, Université Paris 06, Centre d'Immunologie et des Maladies Infectieuses, Paris, Assistance Publique-Hôpitaux de Paris, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux, Bactériologie-Hygiène, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, Paris, France.
Summary
Early suspicion of extensively drug-resistant tuberculosis (XDR-TB) is crucial. Foreign birth, prior treatment, and ethambutol resistance are key indicators for XDR-TB in multidrug-resistant tuberculosis cases.
Area of Science:
- Infectious Diseases
- Microbiology
- Public Health
Background:
- Extensively drug-resistant tuberculosis (XDR-TB) identification is often delayed due to limited molecular testing for second-line drugs (SLDs).
- Early suspicion of XDR-TB is vital to prevent further antimicrobial resistance development.
Purpose of the Study:
- To identify characteristics associated with XDR-TB among multidrug-resistant tuberculosis (MDR-TB) cases prior to second-line drug susceptibility testing (DST) results.
- To inform early clinical suspicion and targeted testing strategies for XDR-TB.
Main Methods:
- Retrospective analysis of MDR-TB cases with available second-line DST results in France (1998-2013).
- Classification of cases into simple MDR-TB, pre-XDR-TB, and XDR-TB based on resistance to fluoroquinolones (FQs) and second-line injectable drugs (SLIDs).
- Multivariable logistic regression to identify independent predictors of XDR-TB and pre-XDR-TB.
Main Results:
- Out of 833 MDR-TB cases, 62 (7%) were XDR-TB and 168 (20%) were pre-XDR-TB.
- Independent predictors for XDR-TB included foreign birth (OR 9.5), previous anti-tuberculosis treatment (OR 2.6), smear positivity (OR 4.5), and ethambutol (EMB) resistance (OR 9.1).
- Independent predictors for pre-XDR-TB included male sex (OR 1.6), birth in Europe (OR 2.6), and EMB resistance (OR 1.9).
Conclusions:
- Clinical and bacteriological characteristics associated with XDR-TB should prompt rapid molecular testing for SLD resistance.
- Timely initiation of tailored treatment based on early suspicion and testing can improve outcomes for XDR-TB patients.
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