Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 65
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Lancet ; 403(10422): 147-159, 2024 Jan 13.
Article in English | MEDLINE | ID: mdl-38008109

ABSTRACT

BACKGROUND: Many patients with chronic spontaneous urticaria (CSU) do not achieve complete control of their symptoms with current available treatments. In a dose-finding phase 2b study, ligelizumab improved urticaria symptoms in patients with H1-antihistamine (H1-AH) refractory CSU. Here, we report the efficacy and safety outcomes from two ligelizumab phase 3 studies. METHODS: PEARL-1 and PEARL-2 were identically designed randomised, double-blind, active-controlled and placebo-controlled parallel-group studies. Patients aged 12 years or older with moderate-to-severe H1-AH refractory CSU were recruited from 347 sites in 46 countries and randomly allocated in a 3:3:3:1 ratio via Interactive Response Technology to 72 mg ligelizumab, 120 mg ligelizumab, 300 mg omalizumab, or placebo, dosed every 4 weeks, for 52 weeks. Patients allocated to placebo received 120 mg ligelizumab from week 24. The primary endpoint was change-from-baseline (CFB) in weekly Urticaria Activity Score (UAS7) at week 12, and was analysed in all eligible adult patients according to the treatment assigned at random allocation. Safety was assessed throughout the study in all patients who received at least one dose of the study drug. The studies were registered with ClinicalTrials.gov, NCT03580369 (PEARL-1) and NCT03580356 (PEARL-2). Both trials are now complete. FINDINGS: Between Oct 17, 2018, and Oct 26, 2021, 2057 adult patients were randomly allocated across both studies (72 mg ligelizumab n=614; 120 mg ligelizumab n=616; 300 mg omalizumab n=618, and placebo n=209). A total of 1480 (72%) of 2057 were female, and 577 (28%) of 2057 were male. Mean UAS7 at baseline across study groups ranged from 29·37 to 31·10. At week 12, estimated treatment differences in mean CFB-UAS7 were as follows: for 72 mg ligelizumab versus placebo, -8·0 (95% CI -10·6 to -5·4; PEARL-1), -10·0 (-12·6 to -7·4; PEARL-2); 72 mg ligelizumab versus omalizumab 0·7 (-1·2 to 2·5; PEARL-1), 0·4 (-1·4 to 2·2; PEARL-2); 120 mg ligelizumab versus placebo -8·0 (-10·5 to -5·4; PEARL-1), -11·1 (-13·7 to -8·5; PEARL-2); 120 mg ligelizumab versus omalizumab 0·7 (-1·1 to 2·5; PEARL-1), -0·7 (-2·5 to 1·1; PEARL-2). Both doses of ligelizumab were superior to placebo (p<0·0001), but not to omalizumab, in both studies. No new safety signals were identified for ligelizumab or omalizumab. INTERPRETATION: In the phase 3 PEARL studies, ligelizumab demonstrated superior efficacy versus placebo but not versus omalizumab. The safety profile of ligelizumab was consistent with previous studies. FUNDING: Novartis Pharma.


Subject(s)
Anti-Allergic Agents , Antibodies, Monoclonal, Humanized , Chronic Urticaria , Urticaria , Adolescent , Adult , Female , Humans , Male , Anti-Allergic Agents/adverse effects , Chronic Disease , Chronic Urticaria/drug therapy , Double-Blind Method , Histamine H1 Antagonists/therapeutic use , Omalizumab/adverse effects , Randomized Controlled Trials as Topic , Treatment Outcome , Urticaria/drug therapy
2.
Lancet ; 399(10330): 1141-1153, 2022 03 19.
Article in English | MEDLINE | ID: mdl-35305740

ABSTRACT

BACKGROUND: We aimed to assess the effectiveness of a single dose of the Ad26.COV2.S vaccine (Johnson & Johnson) in health-care workers in South Africa during two waves of the South African COVID-19 epidemic. METHODS: In the single-arm, open-label, phase 3B implementation Sisonke study, health-care workers aged 18 years and older were invited for vaccination at one of 122 vaccination sites nationally. Participants received a single dose of 5 × 1010 viral particles of the Ad26.COV2.S vaccine. Vaccinated participants were linked with their person-level data from one of two national medical insurance schemes (scheme A and scheme B) and matched for COVID-19 risk with an unvaccinated member of the general population. The primary outcome was vaccine effectiveness against severe COVID-19, defined as COVID-19-related admission to hospital, hospitalisation requiring critical or intensive care, or death, in health-care workers compared with the general population, ascertained 28 days or more after vaccination or matching, up to data cutoff. This study is registered with the South African National Clinical Trial Registry, DOH-27-022021-6844, ClinicalTrials.gov, NCT04838795, and the Pan African Clinical Trials Registry, PACTR202102855526180, and is closed to accrual. FINDINGS: Between Feb 17 and May 17, 2021, 477 102 health-care workers were enrolled and vaccinated, of whom 357 401 (74·9%) were female and 119 701 (25·1%) were male, with a median age of 42·0 years (33·0-51·0). 215 813 vaccinated individuals were matched with 215 813 unvaccinated individuals. As of data cutoff (July 17, 2021), vaccine effectiveness derived from the total matched cohort was 83% (95% CI 75-89) to prevent COVID-19-related deaths, 75% (69-82) to prevent COVID-19-related hospital admissions requiring critical or intensive care, and 67% (62-71) to prevent COVID-19-related hospitalisations. The vaccine effectiveness for all three outcomes were consistent across scheme A and scheme B. The vaccine effectiveness was maintained in older health-care workers and those with comorbidities including HIV infection. During the course of the study, the beta (B.1.351) and then the delta (B.1.617.2) SARS-CoV-2 variants of concerns were dominant, and vaccine effectiveness remained consistent (for scheme A plus B vaccine effectiveness against COVID-19-related hospital admission during beta wave was 62% [95% CI 42-76] and during delta wave was 67% [62-71], and vaccine effectiveness against COVID-19-related death during beta wave was 86% [57-100] and during delta wave was 82% [74-89]). INTERPRETATION: The single-dose Ad26.COV2.S vaccine shows effectiveness against severe COVID-19 disease and COVID-19-related death after vaccination, and against both beta and delta variants, providing real-world evidence for its use globally. FUNDING: National Treasury of South Africa, the National Department of Health, Solidarity Response Fund NPC, The Michael & Susan Dell Foundation, The Elma Vaccines and Immunization Foundation, and the Bill & Melinda Gates Foundation.


Subject(s)
COVID-19 , HIV Infections , Vaccines , Ad26COVS1 , Adolescent , Adult , Aged , COVID-19/epidemiology , COVID-19/prevention & control , Female , Humans , Male , SARS-CoV-2 , South Africa/epidemiology
3.
Allergy ; 77(7): 2185-2199, 2022 07.
Article in English | MEDLINE | ID: mdl-34862605

ABSTRACT

BACKGROUND: Cold urticaria (ColdU), that is, the occurrence of wheals or angioedema in response to cold exposure, is classified into typical and atypical forms. The diagnosis of typical ColdU relies on whealing in response to local cold stimulation testing (CST). It can also manifest with cold-induced anaphylaxis (ColdA). We aimed to determine risk factors for ColdA in typical ColdU. METHODS: An international, cross-sectional study COLD-CE was carried out at 32 urticaria centers of reference and excellence (UCAREs). Detailed history was taken and CST with an ice cube and/or TempTest® performed. ColdA was defined as an acute cold-induced involvement of the skin and/or visible mucosal tissue and at least one of: cardiovascular manifestations, difficulty breathing, or gastrointestinal symptoms. RESULTS: Of 551 ColdU patients, 75% (n = 412) had a positive CST and ColdA occurred in 37% (n = 151) of the latter. Cold-induced generalized wheals, angioedema, acral swelling, oropharyngeal/laryngeal symptoms, and itch of earlobes were identified as signs/symptoms of severe disease. ColdA was most commonly provoked by complete cold water immersion and ColdA caused by cold air was more common in countries with a warmer climate. Ten percent (n = 40) of typical ColdU patients had a concomitant chronic spontaneous urticaria (CSU). They had a lower frequency of ColdA than those without CSU (4% vs. 39%, p = .003). We identified the following risk factors for cardiovascular manifestations: previous systemic reaction to a Hymenoptera sting, angioedema, oropharyngeal/laryngeal symptoms, and itchy earlobes. CONCLUSION: ColdA is common in typical ColdU. High-risk patients require education about their condition and how to use an adrenaline autoinjector.


Subject(s)
Angioedema , Chronic Urticaria , Hymenoptera , Insect Bites and Stings , Urticaria , Angioedema/diagnosis , Angioedema/epidemiology , Angioedema/etiology , Animals , Cold Temperature , Cross-Sectional Studies , Humans , Insect Bites and Stings/complications , Pruritus/complications , Risk Factors , Urticaria/diagnosis , Urticaria/epidemiology , Urticaria/etiology
4.
Qatar Med J ; 2022(2): 19, 2022.
Article in English | MEDLINE | ID: mdl-35909392

ABSTRACT

Background: The diagnosis of typical cold urticaria (ColdU) relies on whealing in response to local cold stimulation testing (CST). It can also manifest with cold-induced anaphylaxis (ColdA). Till date, it is largely unclear how often patients with ColdU receive adrenaline treatment and are provided with an adrenaline autoinjector (AAI). Methods: An international, cross-sectional study, COLD-CE (i.e., comprehensive evaluation of ColdU and other cold-induced reactions), was carried out at 32 UCAREs. Detailed histories were taken and CST with an ice cube and/or TempTest® performed. ColdA was defined as an acute cold-induced (i.e., by cold water, air, or surfaces) involvement of the skin and/or visible mucosal tissue and at least one of the symptoms (cardiovascular manifestations, difficulty breathing, or gastrointestinal symptoms). Results: Of the 551 ColdU patients, 75% (n = 412) had a positive CST. Of them, concomitant chronic spontaneous urticaria was diagnosed in 10%. Of 372 patients with stand-alone ColdU, 69% were women and 91% adults. Their median age was 36 (IQR 26 - 48) years. Patients were also categorized into residents of countries with a tropical (n = 33), temperate (n = 264), or cold (n = 75) climate (Table 1: R13C1, R17C1, R21C1). AAI was more often prescribed to residents of temperate than tropical countries (30% vs. 12%, p = .038; Table 1: R31C1), although the frequency of ColdA did not significantly differ between these countries (44% vs. 42%, p = 1.000; R29C2). Residents of tropical countries had a higher frequency of ColdA induced by cold air than residents of temperate (36% vs. 12%, p = .001; R29C4) or cold (36% vs. 12%, p = .007; R25C4) countries. Cardiovascular manifestations induced by cold air were diagnosed in 33% (n = 11) of residents of tropical countries, but only 18% (n = 2) and 36% (n = 4) of them had received adrenaline and AAI, respectively (R13 - 15C7). Furthermore, hypotension and/or loss of consciousness induced by cold air occurred in 18% (n = 6) of patients, but only 17% (n = 1) received adrenaline (R13 - 14C10). ColdA was induced by complete cold water immersion in 9% (n = 3) of patients, and none of them received adrenaline treatment nor AAI (R13 - 15C3). Conclusion: Our findings suggest that ColdA is undertreated and call for changes in ColdU management.

5.
Allergy ; 76(3): 816-830, 2021 03.
Article in English | MEDLINE | ID: mdl-33284457

ABSTRACT

INTRODUCTION: The COVID-19 pandemic dramatically disrupts health care around the globe. The impact of the pandemic on chronic urticaria (CU) and its management are largely unknown. AIM: To understand how CU patients are affected by the COVID-19 pandemic; how specialists alter CU patient management; and the course of CU in patients with COVID-19. MATERIALS AND METHODS: Our cross-sectional, international, questionnaire-based, multicenter UCARE COVID-CU study assessed the impact of the pandemic on patient consultations, remote treatment, changes in medications, and clinical consequences. RESULTS: The COVID-19 pandemic severely impairs CU patient care, with less than 50% of the weekly numbers of patients treated as compared to before the pandemic. Reduced patient referrals and clinic hours were the major reasons. Almost half of responding UCARE physicians were involved in COVID-19 patient care, which negatively impacted on the care of urticaria patients. The rate of face-to-face consultations decreased by 62%, from 90% to less than half, whereas the rate of remote consultations increased by more than 600%, from one in 10 to more than two thirds. Cyclosporine and systemic corticosteroids, but not antihistamines or omalizumab, are used less during the pandemic. CU does not affect the course of COVID-19, but COVID-19 results in CU exacerbation in one of three patients, with higher rates in patients with severe COVID-19. CONCLUSIONS: The COVID-19 pandemic brings major changes and challenges for CU patients and their physicians. The long-term consequences of these changes, especially the increased use of remote consultations, require careful evaluation.


Subject(s)
COVID-19/epidemiology , Chronic Urticaria/therapy , SARS-CoV-2 , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Humans , Internet , Male , Middle Aged , Patient Reported Outcome Measures , Young Adult
6.
Lancet ; 393(10167): 183-198, 2019 01 12.
Article in English | MEDLINE | ID: mdl-30558872

ABSTRACT

Antibiotics are the commonest cause of life-threatening immune-mediated drug reactions that are considered off-target, including anaphylaxis, and organ-specific and severe cutaneous adverse reactions. However, many antibiotic reactions documented as allergies were unknown or not remembered by the patient, cutaneous reactions unrelated to drug hypersensitivity, drug-infection interactions, or drug intolerances. Although such reactions pose negligible risk to patients, they currently represent a global threat to public health. Antibiotic allergy labels result in displacement of first-line therapies for antibiotic prophylaxis and treatment. A penicillin allergy label, in particular, is associated with increased use of broad-spectrum and non-ß-lactam antibiotics, which results in increased adverse events and antibiotic resistance. Most patients labelled as allergic to penicillins are not allergic when appropriately stratified for risk, tested, and re-challenged. Given the public health importance of penicillin allergy, this Review provides a global update on antibiotic allergy epidemiology, classification, mechanisms, and management.


Subject(s)
Anti-Bacterial Agents/adverse effects , Drug Hypersensitivity , Penicillins/adverse effects , Anaphylaxis/etiology , Cross Infection/epidemiology , Cross Infection/therapy , Drug Hypersensitivity/classification , Drug Hypersensitivity/diagnosis , Drug Hypersensitivity/epidemiology , Drug Hypersensitivity/therapy , Drug Resistance, Microbial , Female , Global Health , Humans , Male , Risk Factors , beta-Lactamases/adverse effects
7.
J Allergy Clin Immunol ; 143(1): 66-73, 2019 01.
Article in English | MEDLINE | ID: mdl-30573342

ABSTRACT

Controversies exist with regard to in vivo approaches to delayed immunologically mediated adverse drug reactions, such as exanthem (maculopapular eruption), drug reaction with eosinophilia and systemic symptoms, acute generalized exanthematous pustulosis, Stevens-Johnson syndrome/toxic epidermal necrolysis, and fixed drug eruptions. In particular, widespread differences exist between regions and practice on the availability and use of intradermal and patch testing, the standard drug concentrations used, the use of additional drugs in intradermal and patch testing to help determine cross-reactivity, the timing of testing in relation to the occurrence of the adverse drug reaction, the use of testing in specific phenotypes, and the use of oral challenge in conjunction with delayed intradermal and patch testing to ascertain drug tolerance. It was noted that there have been advances in the science of delayed T cell-mediated reactions that have shed light on immunopathogenesis and provided a mechanism of preprescription screening in the case of HLA-B*57:01 and abacavir hypersensitivity and HLA-B*15:02 and carbamazepine Stevens-Johnson syndrome/toxic epidermal necrolysis in Southeast Asian subjects. Future directions should include the collaboration of large international networks to develop and standardize in vivo diagnostic approaches, such as skin testing and patch testing, combined with ex vivo and in vitro laboratory approaches.


Subject(s)
HLA-B Antigens , HLA-B15 Antigen , Stevens-Johnson Syndrome , Animals , Asian People , Carbamazepine/adverse effects , Carbamazepine/therapeutic use , Dideoxynucleosides/adverse effects , Dideoxynucleosides/therapeutic use , HLA-B Antigens/genetics , HLA-B Antigens/immunology , HLA-B15 Antigen/genetics , HLA-B15 Antigen/immunology , Humans , Skin Tests/standards , Stevens-Johnson Syndrome/genetics , Stevens-Johnson Syndrome/immunology , Stevens-Johnson Syndrome/pathology
8.
PLoS Med ; 16(4): e1002776, 2019 04.
Article in English | MEDLINE | ID: mdl-30951533

ABSTRACT

BACKGROUND: The prevalence of and mortality from HIV-associated tuberculosis (HIV/TB) in hospital inpatients in Africa remains unacceptably high. Currently, there is a lack of tools to identify those at high risk of early mortality who may benefit from adjunctive interventions. We therefore aimed to develop and validate a simple clinical risk score to predict mortality in high-burden, low-resource settings. METHODS AND FINDINGS: A cohort of HIV-positive adults with laboratory-confirmed TB from the STAMP TB screening trial (Malawi and South Africa) was used to derive a clinical risk score using multivariable predictive modelling, considering factors at hospital admission (including urine lipoarabinomannan [LAM] detection) thought to be associated with 2-month mortality. Performance was evaluated internally and then externally validated using independent cohorts from 2 other studies (LAM-RCT and a Médecins Sans Frontières [MSF] cohort) from South Africa, Zambia, Zimbabwe, Tanzania, and Kenya. The derivation cohort included 315 patients enrolled from October 2015 and September 2017. Their median age was 36 years (IQR 30-43), 45.4% were female, median CD4 cell count at admission was 76 cells/µl (IQR 23-206), and 80.2% (210/262) of those who knew they were HIV-positive at hospital admission were taking antiretroviral therapy (ART). Two-month mortality was 30% (94/315), and mortality was associated with the following factors included in the score: age 55 years or older, male sex, being ART experienced, having severe anaemia (haemoglobin < 80 g/l), being unable to walk unaided, and having a positive urinary Determine TB LAM Ag test (Alere). The score identified patients with a 46.4% (95% CI 37.8%-55.2%) mortality risk in the high-risk group compared to 12.5% (95% CI 5.7%-25.4%) in the low-risk group (p < 0.001). The odds ratio (OR) for mortality was 6.1 (95% CI 2.4-15.2) in high-risk patients compared to low-risk patients (p < 0.001). Discrimination (c-statistic 0.70, 95% CI 0.63-0.76) and calibration (Hosmer-Lemeshow statistic, p = 0.78) were good in the derivation cohort, and similar in the external validation cohort (complete cases n = 372, c-statistic 0.68 [95% CI 0.61-0.74]). The validation cohort included 644 patients between January 2013 and August 2015. Median age was 36 years, 48.9% were female, and median CD4 count at admission was 61 (IQR 21-145). OR for mortality was 5.3 (95% CI 2.2-9.5) for high compared to low-risk patients (complete cases n = 372, p < 0.001). The score also predicted patients at higher risk of death both pre- and post-discharge. A simplified score (any 3 or more of the predictors) performed equally well. The main limitations of the scores were their imperfect accuracy, the need for access to urine LAM testing, modest study size, and not measuring all potential predictors of mortality (e.g., tuberculosis drug resistance). CONCLUSIONS: This risk score is capable of identifying patients who could benefit from enhanced clinical care, follow-up, and/or adjunctive interventions, although further prospective validation studies are necessary. Given the scale of HIV/TB morbidity and mortality in African hospitals, better prognostic tools along with interventions could contribute towards global targets to reduce tuberculosis mortality.


Subject(s)
HIV Infections/diagnosis , HIV Infections/mortality , Lipopolysaccharides/urine , Tuberculosis/diagnosis , Tuberculosis/mortality , AIDS-Related Opportunistic Infections/diagnosis , AIDS-Related Opportunistic Infections/mortality , AIDS-Related Opportunistic Infections/urine , Adult , Africa South of the Sahara/epidemiology , Cohort Studies , Female , HIV , HIV Infections/complications , HIV Infections/urine , Hospitalization , Humans , Inpatients , Male , Mass Screening/methods , Prognosis , Research Design , Risk Factors , Survival Analysis , Tuberculosis/urine , Urinalysis
10.
BMC Palliat Care ; 18(1): 101, 2019 Nov 13.
Article in English | MEDLINE | ID: mdl-31722691

ABSTRACT

BACKGROUND: Timely identification of people who are at risk of dying is an important first component of end-of-life care. Clinicians often fail to identify such patients, thus trigger tools have been developed to assist in this process. We aimed to evaluate the performance of a identification tool (based on the Gold Standards Framework Prognostic Indicator Guidance) to predict death at 12 months in a population of hospitalised patients in South Africa. METHODS: Patients admitted to the acute medical services in two public hospitals in Cape Town, South Africa were enrolled in a prospective observational study. Demographic data were collected from patients and patient notes. Patients were assessed within two days of admission by two trained clinicians who were not the primary care givers, using the identification tool. Outcome mortality data were obtained from patient folders, the hospital electronic patient management system and the Western Cape Provincial death registry which links a unique patient identification number with national death certificate records and system wide electronic records. RESULTS: 822 patients (median age of 52 years), admitted with a variety of medical conditions were assessed during their admission. 22% of the cohort were HIV-infected. 218 patients were identified using the screening tool as being in the last year of their lives. Mortality in this group was 56% at 12 months, compared with 7% for those not meeting any criteria. The specific indicator component of the tool performed best in predicting death in both HIV-infected and HIV-uninfected patients, with a sensitivity of 74% (68-81%), specificity of 85% (83-88%), a positive predictive value of 56% (49-63%) and a negative predictive value of 93% (91-95%). The hazard ratio of 12-month mortality for those identified vs not was 11.52 (7.87-16.9, p < 0.001). CONCLUSIONS: The identification tool is suitable for use in hospitals in low-middle income country setting that have both a high communicable and non-communicable disease burden amongst young patients, the majority under age 60.


Subject(s)
Communicable Diseases/epidemiology , Noncommunicable Diseases/epidemiology , Palliative Care/organization & administration , Acute Coronary Syndrome/epidemiology , Adult , Aged , Aged, 80 and over , Communicable Diseases/mortality , Female , HIV Infections/epidemiology , Hospitals, Public , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Palliative Care/standards , Prognosis , Prospective Studies , Sensitivity and Specificity , Socioeconomic Factors , South Africa/epidemiology , Stroke/epidemiology , Tuberculosis/epidemiology
11.
Lancet ; 387(10024): 1187-97, 2016 Mar 19.
Article in English | MEDLINE | ID: mdl-26970721

ABSTRACT

BACKGROUND: HIV-associated tuberculosis is difficult to diagnose and results in high mortality. Frequent extra-pulmonary presentation, inability to obtain sputum, and paucibacillary samples limits the usefulness of nucleic-acid amplification tests and smear microscopy. We therefore assessed a urine-based, lateral flow, point-of-care, lipoarabinomannan assay (LAM) and the effect of a LAM-guided anti-tuberculosis treatment initiation strategy on mortality. METHODS: We did a pragmatic, randomised, parallel-group, multicentre trial in ten hospitals in Africa--four in South Africa, two in Tanzania, two in Zambia, and two in Zimbabwe. Eligible patients were HIV-positive adults aged at least 18 years with at least one of the following symptoms of tuberculosis (fever, cough, night sweats, or self-reported weightloss) and illness severity necessitating admission to hospital. Exclusion criteria included receipt of any anti-tuberculosis medicine in the 60 days before enrolment. We randomly assigned patients (1:1) to either LAM plus routine diagnostic tests for tuberculosis (smear microscopy, Xpert-MTB/RIF, and culture; LAM group) or routine diagnostic tests alone (no LAM group) using computer-generated allocation lists in blocks of ten. All patients were asked to provide a urine sample of at least 30 mL at enrolment, and trained research nurses did the LAM test in patients allocated to this group using the Alere Determine tuberculosis LAM Ag lateral flow strip test (Alere, USA) at the bedside on enrolment. On the basis of a positive test result, the nurses made a recommendation for initiating anti-tuberculosis treatment. The attending physician made an independent decision about whether to start treatment or not. Neither patients nor health-care workers were masked to group allocation and test results. The primary endpoint was 8-week all-cause mortality assessed in the modified intention-to-treat population (those who received their allocated intervention). This trial is registered with ClinicalTrials.gov, number NCT01770730. FINDINGS: Between Jan 1, 2013, and Oct 2, 2014, we screened 8728 patients and randomly assigned 2659 to treatment (1336 to LAM, 1323 to no LAM). 108 patients did not receive their allocated treatment, mainly because they did not meet the inclusion criteria, and 23 were excluded from analysis, leaving 2528 in the final modified intention-to-treat analysis (1257 in the LAM group, 1271 in the no LAM group). Overall all-cause 8-week mortality occurred in 578 (23%) patients, 261 (21%) in LAM and 317 (25%) in no LAM, an absolute reduction of 4% (95% CI 1-7). The risk ratio adjusted for country was 0·83 (95% CI 0·73-0·96), p=0·012, with a relative risk reduction of 17% (95% CI 4-28). With the time-to-event analysis, there were 159 deaths per 100 person-years in LAM and 196 per 100 person-years in no LAM (hazard ratio adjusted for country 0·82 [95% CI 0·70-0·96], p=0·015). No adverse events were associated with LAM testing. INTERPRETATION: Bedside LAM-guided initiation of anti-tuberculosis treatment in HIV-positive hospital inpatients with suspected tuberculosis was associated with reduced 8-week mortality. The implementation of LAM testing is likely to offer the greatest benefit in hospitals where diagnostic resources are most scarce and where patients present with severe illness, advanced immunosuppression, and an inability to self-expectorate sputum. FUNDING: European Developing Clinical Trials Partnership, the South African Medical Research Council, and the South African National Research Foundation.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , Lipopolysaccharides/urine , Point-of-Care Systems , Tuberculosis/diagnosis , AIDS-Related Opportunistic Infections/drug therapy , AIDS-Related Opportunistic Infections/immunology , AIDS-Related Opportunistic Infections/mortality , Adult , Africa/epidemiology , Antitubercular Agents/therapeutic use , Biomarkers/urine , CD4 Lymphocyte Count , Diagnostic Tests, Routine , Female , Hospitalization , Humans , Length of Stay/statistics & numerical data , Male , Sensitivity and Specificity , Treatment Outcome , Tuberculosis/drug therapy , Tuberculosis/immunology , Tuberculosis/mortality
14.
BMC Infect Dis ; 17(1): 339, 2017 05 12.
Article in English | MEDLINE | ID: mdl-28499418

ABSTRACT

BACKGROUND: Urine LAM testing has been approved by the WHO for use in hospitalised patients with advanced immunosuppression. However, sensitivity remains suboptimal. We therefore examined the incremental diagnostic sensitivity of early morning urine (EMU) versus random urine sampling using the Determine® lateral flow lipoarabinomannan assay (LF-LAM) in HIV-TB co-infected patients. METHODS: Consenting HIV-infected inpatients, screened as part of a larger prospective randomized controlled trial, that were treated for TB, and could donate matched random and EMU samples were included. Thus paired sample were collected from the same patient, LF-LAM was graded using the pre-January 2014, with grade 1 and 2 manufacturer-designated cut-points (the latter designated grade 1 after January 2014). Single sputum Xpert-MTB/RIF and/or TB culture positivity served as the reference standard (definite TB). Those treated for TB but not meeting this standard were designated probable TB. RESULTS: 123 HIV-infected patients commenced anti-TB treatment and provided matched random and EMU samples. 33% (41/123) and 67% (82/123) had definite and probable TB, respectively. Amongst those with definite TB LF-LAM sensitivity (95%CI), using the grade 2 cut-point, increased from 12% (5-24; 5/43) to 39% (26-54; 16/41) with random versus EMU, respectively (p = 0.005). Similarly, amongst probable TB, LF-LAM sensitivity increased from 10% (5-17; 8/83) to 24% (16-34; 20/82) (p = 0.001). LF-LAM specificity was not determined. CONCLUSION: This proof of concept study indicates that EMU could improve the sensitivity of LF-LAM in hospitalised TB-HIV co-infected patients. These data have implications for clinical practice.


Subject(s)
HIV Infections/microbiology , Lipopolysaccharides/urine , Tuberculosis/urine , Urinalysis/methods , Urine Specimen Collection/methods , AIDS-Related Opportunistic Infections/urine , Adult , Female , HIV Infections/complications , Humans , Male , Prospective Studies , Sensitivity and Specificity , Sputum/microbiology , Tuberculosis/diagnosis
15.
Clin Infect Dis ; 62(8): 995-1001, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26908793

ABSTRACT

BACKGROUND: Patients with previous tuberculosis may have residual DNA in sputum that confounds nucleic acid amplification tests such as Xpert MTB/RIF. Little is known about the frequency of Xpert-positive, culture-negative ("false positive") results in retreatment patients, whether these are distinguishable from true positives, and whether Xpert's automated filter-based wash step reduces false positivity by removing residual DNA associated with nonintact cells. METHODS: Pretreatment patients (n = 2889) with symptoms of tuberculosis from Cape Town, South Africa, underwent a sputum-based liquid culture and Xpert. We also compared Xpert results from dilutions of intact or heat-lysed and mechanically lysed bacilli. RESULTS: Retreatment cases were more likely to be Xpert false-positive (45/321 Xpert-positive retreatment cases were false-positive) than new cases (40/461) (14% [95% confidence interval {CI}, 10%-18%] vs 8% [95% CI, 6%-12%];P= .018). Fewer years since treatment completion (adjusted odds ratio [aOR], 0.85 [95% CI, .73-.99]), less mycobacterial DNA (aOR, 1.14 [95% CI, 1.03-1.27] per cycle threshold [CT]), and a chest radiograph not suggestive of active tuberculosis (aOR, 0.22 [95% CI, .06-.82]) were associated with false positivity. CThad suboptimal accuracy for false positivity: 46% of Xpert-positives with CT> 30 would be false positive, although 70% of false positives would be missed. CT's predictive ability (area under the curve, 0.83 [95% CI, .76-.90]) was not improved by additional variables. Xpert detected nonviable, nonintact bacilli without a change in CTvs controls. CONCLUSIONS: One in 7 Xpert-positive retreatment patients were culture negative and potentially false positive. False positivity was associated with recent previous tuberculosis, high CT, and a chest radiograph not suggestive of active tuberculosis. Clinicians may consider awaiting confirmatory testing in retreatment patients with CT> 30; however, most false positives fall below this cut-point. Xpert can detect DNA from nonviable, nonintact bacilli.


Subject(s)
Nucleic Acid Amplification Techniques , Tuberculosis/diagnosis , Adult , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , False Positive Reactions , Female , Humans , Male , Middle Aged , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , ROC Curve , Reagent Kits, Diagnostic , Sensitivity and Specificity , South Africa/epidemiology , Sputum/microbiology , Tuberculosis/drug therapy , Tuberculosis/microbiology
16.
Cochrane Database Syst Rev ; 9: CD010705, 2016 Sep 08.
Article in English | MEDLINE | ID: mdl-27605387

ABSTRACT

BACKGROUND: Genotype® MTBDRsl (MTBDRsl) is a rapid DNA-based test for detecting specific mutations associated with resistance to fluoroquinolones and second-line injectable drugs (SLIDs) in Mycobacterium tuberculosis complex. MTBDRsl version 2.0 (released in 2015) identifies the mutations detected by version 1.0, as well as additional mutations. The test may be performed on a culture isolate or a patient specimen, which eliminates delays associated with culture. Version 1.0 requires a smear-positive specimen, while version 2.0 may use a smear-positive or -negative specimen. We performed this updated review as part of a World Health Organization process to develop updated guidelines for using MTBDRsl. OBJECTIVES: To assess and compare the diagnostic accuracy of MTBDRsl for: 1. fluoroquinolone resistance, 2. SLID resistance, and 3. extensively drug-resistant tuberculosis, indirectly on a M. tuberculosis isolate grown from culture or directly on a patient specimen. Participants were people with rifampicin-resistant or multidrug-resistant tuberculosis. The role of MTBDRsl would be as the initial test, replacing culture-based drug susceptibility testing (DST), for detecting second-line drug resistance. SEARCH METHODS: We searched the following databases without language restrictions up to 21 September 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE; Embase OVID; Science Citation Index Expanded, Conference Proceedings Citation Index-Science, and BIOSIS Previews (all three from Web of Science); LILACS; and SCOPUS; registers for ongoing trials; and ProQuest Dissertations & Theses A&I. We reviewed references from included studies and contacted specialists in the field. SELECTION CRITERIA: We included cross-sectional and case-control studies that determined MTBDRsl accuracy against a defined reference standard (culture-based DST, genetic sequencing, or both). DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. We synthesized data for versions 1.0 and 2.0 separately. We estimated MTBDRsl sensitivity and specificity for fluoroquinolone resistance, SLID resistance, and extensively drug-resistant tuberculosis when the test was performed indirectly or directly (smear-positive specimen for version 1.0, smear-positive or -negative specimen for version 2.0). We explored the influence on accuracy estimates of individual drugs within a drug class and of different reference standards. We performed most analyses using a bivariate random-effects model with culture-based DST as reference standard. MAIN RESULTS: We included 27 studies. Twenty-six studies evaluated version 1.0, and one study version 2.0. Of 26 studies stating specimen country origin, 15 studies (58%) evaluated patients from low- or middle-income countries. Overall, we considered the studies to be of high methodological quality. However, only three studies (11%) had low risk of bias for the reference standard; these studies used World Health Organization (WHO)-recommended critical concentrations for all drugs in the culture-based DST reference standard. MTBDRsl version 1.0 Fluoroquinolone resistance: indirect testing, MTBDRsl pooled sensitivity and specificity (95% confidence interval (CI)) were 85.6% (79.2% to 90.4%) and 98.5% (95.7% to 99.5%), (19 studies, 2223 participants); direct testing (smear-positive specimen), pooled sensitivity and specificity were 86.2% (74.6% to 93.0%) and 98.6% (96.9% to 99.4%), (nine studies, 1771 participants, moderate quality evidence). SLID resistance: indirect testing, MTBDRsl pooled sensitivity and specificity were 76.5% (63.3% to 86.0%) and 99.1% (97.3% to 99.7%), (16 studies, 1921 participants); direct testing (smear-positive specimen), pooled sensitivity and specificity were 87.0% (38.1% to 98.6%) and 99.5% (93.6% to 100.0%), (eight studies, 1639 participants, low quality evidence). Extensively drug-resistant tuberculosis: indirect testing, MTBDRsl pooled sensitivity and specificity were 70.9% (42.9% to 88.8%) and 98.8% (96.1% to 99.6%), (eight studies, 880 participants); direct testing (smear-positive specimen), pooled sensitivity and specificity were 69.4% (38.8% to 89.0%) and 99.4% (95.0% to 99.3%), (six studies, 1420 participants, low quality evidence).Similar to the original Cochrane review, we found no evidence of a significant difference in MTBDRsl version 1.0 accuracy between indirect and direct testing for fluoroquinolone resistance, SLID resistance, and extensively drug-resistant tuberculosis. MTBDRsl version 2.0 Fluoroquinolone resistance: direct testing, MTBDRsl sensitivity and specificity were 97% (83% to 100%) and 98% (93% to 100%), smear-positive specimen; 80% (28% to 99%) and 100% (40% to 100%), smear-negative specimen. SLID resistance: direct testing, MTBDRsl sensitivity and specificity were 89% (72% to 98%) and 90% (84% to 95%), smear-positive specimen; 80% (28% to 99%) and 100% (40% to 100%), smear-negative specimen. Extensively drug-resistant tuberculosis: direct testing, MTBDRsl sensitivity and specificity were 79% (49% to 95%) and 97% (93% to 99%), smear-positive specimen; 50% (1% to 99%) and 100% (59% to 100%), smear-negative specimen.We had insufficient data to estimate summary sensitivity and specificity of version 2.0 (smear-positive and -negative specimens) or to compare accuracy of the two versions.A limitation was that most included studies did not consistently use the World Health Organization (WHO)-recommended concentrations for drugs in the culture-based DST reference standard. AUTHORS' CONCLUSIONS: In people with rifampicin-resistant or multidrug-resistant tuberculosis, MTBDRsl performed on a culture isolate or smear-positive specimen may be useful in detecting second-line drug resistance. MTBDRsl (smear-positive specimen) correctly classified around six in seven people as having fluoroquinolone or SLID resistance, although the sensitivity estimates for SLID resistance varied. The test rarely gave a positive result for people without drug resistance. However, when second-line drug resistance is not detected (MTBDRsl result is negative), conventional DST can still be used to evaluate patients for resistance to the fluoroquinolones or SLIDs.We recommend that future work evaluate MTBDRsl version 2.0, in particular on smear-negative specimens and in different settings to account for different resistance-causing mutations that may vary by strain. Researchers should also consider incorporating WHO-recommended critical concentrations into their culture-based reference standards.

17.
Lancet ; 383(9915): 424-35, 2014 Feb 01.
Article in English | MEDLINE | ID: mdl-24176144

ABSTRACT

BACKGROUND: The Xpert MTB/RIF test for tuberculosis is being rolled out in many countries, but evidence is lacking regarding its implementation outside laboratories, ability to inform same-day treatment decisions at the point of care, and clinical effect on tuberculosis-related morbidity. We aimed to assess the feasibility, accuracy, and clinical effect of point-of-care Xpert MTB/RIF testing at primary-care health-care facilities in southern Africa. METHODS: In this pragmatic, randomised, parallel-group, multicentre trial, we recruited adults with symptoms suggestive of active tuberculosis from five primary-care health-care facilities in South Africa, Zimbabwe, Zambia, and Tanzania. Eligible patients were randomly assigned using pregenerated tables to nurse-performed Xpert MTB/RIF at the clinic or sputum smear microscopy. Participants with a negative test result were empirically managed according to local WHO-compliant guidelines. Our primary outcome was tuberculosis-related morbidity (measured with the TBscore and Karnofsky performance score [KPS]) in culture-positive patients who had begun anti-tuberculosis treatment, measured at 2 months and 6 months after randomisation, analysed by intention to treat. This trial is registered with Clinicaltrials.gov, number NCT01554384. FINDINGS: Between April 12, 2011, and March 30, 2012, we randomly assigned 758 patients to smear microscopy (182 culture positive) and 744 to Xpert MTB/RIF (185 culture positive). Median TBscore in culture-positive patients did not differ between groups at 2 months (2 [IQR 0-3] in the smear microscopy group vs 2 [0·25-3] in the MTB/RIF group; p=0·85) or 6 months (1 [0-3] vs 1 [0-3]; p=0·35), nor did median KPS at 2 months (80 [70-90] vs 90 [80-90]; p=0·23) or 6 months (100 [90-100] vs 100 [90-100]; p=0·85). Point-of-care MTB/RIF had higher sensitivity than microscopy (154 [83%] of 185 vs 91 [50%] of 182; p=0·0001) but similar specificity (517 [95%] 544 vs 540 [96%] of 560; p=0·25), and had similar sensitivity to laboratory-based MTB/RIF (292 [83%] of 351; p=0·99) but higher specificity (952 [92%] of 1037; p=0·0173). 34 (5%) of 744 tests with point-of-care MTB/RIF and 82 (6%) of 1411 with laboratory-based MTB/RIF failed (p=0·22). Compared with the microscopy group, more patients in the MTB/RIF group had a same-day diagnosis (178 [24%] of 744 vs 99 [13%] of 758; p<0·0001) and same-day treatment initiation (168 [23%] of 744 vs 115 [15%] of 758; p=0·0002). Although, by end of the study, more culture-positive patients in the MTB/RIF group were on treatment due to reduced dropout (15 [8%] of 185 in the MTB/RIF group did not receive treatment vs 28 [15%] of 182 in the microscopy group; p=0·0302), the proportions of all patients on treatment in each group by day 56 were similar (320 [43%] of 744 in the MTB/RIF group vs 317 [42%] of 758 in the microscopy group; p=0·6408). INTERPRETATION: Xpert MTB/RIF can be accurately administered by a nurse in primary-care clinics, resulting in more patients starting same-day treatment, more culture-positive patients starting therapy, and a shorter time to treatment. However, the benefits did not translate into lower tuberculosis-related morbidity, partly because of high levels of empirical-evidence-based treatment in smear-negative patients. FUNDING: European and Developing Countries Clinical Trials Partnership, National Research Foundation, and Claude Leon Foundation.


Subject(s)
Point-of-Care Systems/standards , Tuberculosis, Pulmonary/diagnosis , Adult , Africa , Bacteriological Techniques/standards , Feasibility Studies , Female , Humans , Male , Middle Aged , Primary Health Care , Sputum/microbiology , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/nursing , Tuberculosis, Pulmonary/nursing
18.
BMC Infect Dis ; 15: 262, 2015 Jul 09.
Article in English | MEDLINE | ID: mdl-26156025

ABSTRACT

BACKGROUND: The commercially available urine LAM strip test, a point-of-care tuberculosis (TB) assay, requires evaluation in a primary care setting where it is most needed. There is currently inadequate data to guide implementation in TB and HIV-endemic settings. METHODS: Adult HIV-infected outpatients with suspected pulmonary TB able to self-expectorate sputum from four primary clinics in South Africa, Zambia and Tanzania underwent diagnostic evaluation [sputum smear microscopy, Xpert-MTB/RIF, and culture (reference standard)] as part of a prospective parent study. Urine LAM testing (grade-2 cut-point) was performed on archived samples. Performance characteristics of LAM alone or in combination with sputum-based diagnostics were evaluated. Potential impact on 2 and 6-month morbidity (TBscore), patient dropout rates, and prognosis (death/ loss to follow-up) were evaluated. RESULTS: Among 583 participants with suspected TB that were HIV-infected or refused testing, the overall LAM sensitivity (95 % CI; n/N) and in the CD4 ≤ 100 cells/mm(3) sub-group was 22.7 % (16.6-28.7; 41/181) and 30.4 % (17.1-43.7; 14/46), respectively. Overall specificity was 93.0 % (90.5-95.6; 361/388). Amongst culture-positive TB cases, adjunctive LAM testing did not improve the sensitivity of either sputum Xpert-MTB/RIF [78.2 % (69.8-86.7; 72/92) versus 76.1 % (67.4-84.8; 70/92), p = 0.7] or smear-microscopy [56.2 % (45.9-66.5; 50/89) versus 43.8 % (33.5-54.1; 39/89), p = 0.1). Clinic-based LAM, as an adjunct to either smear microscopy or Xpert MTB/RIF same-day testing, would neither have decreased patient dropout, nor increased same-day treatment initiation in this clinical setting where same-day chest radiography was available. LAM positivity was associated with 6-month lost-to-follow-up/death (AOR 4.4; p = 0.002) but not TBscore (at baseline or change in TBscore 2-months post-treatment) (p = 0.17). CONCLUSIONS: In African HIV-TB co-infected outpatients able to self-expectorate sputum LAM had limited sensitivity even at low CD4 counts, and offered no significant incremental diagnostic yield over Xpert-MTB/RIF or smear microscopy. In primary care clinics with chest radiography and where empiric TB treatment is common, LAM seems unlikely to improve rates of same-day treatment initiation and patient dropout, however, the ability of LAM to identify patients at high risk of death or lost-to-follow-up may offer important prognostic value.


Subject(s)
HIV Infections/immunology , Lipopolysaccharides/urine , Sputum/microbiology , Tuberculosis, Pulmonary/diagnosis , Adult , Aged , Ambulatory Care Facilities , Biological Assay , CD4 Lymphocyte Count , Coinfection , Cross-Sectional Studies , Diagnostic Tests, Routine , Female , HIV Infections/complications , Humans , Male , Middle Aged , Outpatients , Point-of-Care Systems , Prospective Studies , Sensitivity and Specificity , South Africa , Tanzania , Tuberculosis/diagnosis , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/immunology , Urinalysis , Young Adult , Zambia
19.
BMC Infect Dis ; 15: 253, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-26126655

ABSTRACT

BACKGROUND: The successful cure of tuberculosis (TB) is dependent on adherence to treatment. Various factors influence adherence, however, few are easily modifiable. There are limited data regarding correlates of psychological distress and their association with non-adherence to anti-TB treatment. METHODS: In a trial of a new TB test, we measured psychological distress (K-10 score), TB-related health literacy, and morbidity (TBscore), prior to diagnosis in 1502 patients with symptoms of pulmonary TB recruited from clinics in Cape Town (n = 419), Harare (n = 400), Lusaka (n = 400), Durban (n = 200), and Mbeya (n = 83). Socioeconomic, demographic, and alcohol usage-related data were captured. Patients initiated on treatment had their DOTS cards reviewed at two-and six-months. RESULTS: 22 %(95 % CI: 20 %, 25 %) of patients had severe psychological distress (K-10 ≥ 30). In a multivariable linear regression model, increased K-10 score was independently associated with previous TB [estimate (95 % CI) 0.98(0.09-1.87); p = 0.0304], increased TBscore [1(0.80, 1.20); p <0.0001], and heavy alcohol use [3.08(1.26, 4.91); p = 0.0010], whereas male gender was protective [-1.47(-2.28, -0.62); p = 0.0007]. 26 % (95 % CI: 21 %, 32 %) of 261 patients with culture-confirmed TB were non-adherent. In a multivariable logistic regression model for non-adherence, reduced TBscore [OR (95 % CI) 0.639 (0.497, 0.797); p = 0.0001], health literacy score [0.798(0.696, 0.906); p = 0.0008], and increased K-10 [1.082(1.033, 1.137); p = 0.0012], and heavy alcohol usage [14.83(2.083, 122.9); p = 0.0002], were independently associated. Culture-positive patients with a K-10 score ≥ 30 were more-likely to be non-adherent (OR = 2.290(1.033-5.126); p = 0.0416]. CONCLUSION: Severe psychological distress is frequent amongst TB patients in Southern Africa. Targeted interventions to alleviate psychological distress, alcohol use, and improve health literacy in newly-diagnosed TB patients could reduce non-adherence to treatment.


Subject(s)
Alcohol Drinking/epidemiology , Antitubercular Agents/therapeutic use , Medication Adherence/statistics & numerical data , Stress, Psychological/epidemiology , Tuberculosis, Pulmonary/drug therapy , Adult , Alcohol Drinking/psychology , Anxiety/epidemiology , Anxiety/psychology , Depression/epidemiology , Depression/psychology , Female , Humans , Logistic Models , Male , Medication Adherence/psychology , Middle Aged , Multivariate Analysis , Sex Factors , South Africa/epidemiology , Stress, Psychological/psychology , Tanzania/epidemiology , Tuberculosis, Pulmonary/epidemiology , Tuberculosis, Pulmonary/psychology , Zambia/epidemiology , Zimbabwe/epidemiology
20.
Cochrane Database Syst Rev ; (10): CD010705, 2014 Oct 29.
Article in English | MEDLINE | ID: mdl-25353401

ABSTRACT

BACKGROUND: Accurate and rapid tests for tuberculosis (TB) drug resistance are critical for improving patient care and decreasing the transmission of drug-resistant TB. Genotype(®)MTBDRsl (MTBDRsl) is the only commercially-available molecular test for detecting resistance in TB to the fluoroquinolones (FQs; ofloxacin, moxifloxacin and levofloxacin) and the second-line injectable drugs (SLIDs; amikacin, kanamycin and capreomycin), which are used to treat patients with multidrug-resistant (MDR-)TB. OBJECTIVES: To obtain summary estimates of the diagnostic accuracy of MTBDRsl for FQ resistance, SLID resistance and extensively drug-resistant TB (XDR-TB; defined as MDR-TB plus resistance to a FQ and a SLID) when performed (1) indirectly (ie on culture isolates confirmed as TB positive) and (2) directly (ie on smear-positive sputum specimens).To compare summary estimates of the diagnostic accuracy of MTBDRsl for FQ resistance, SLID resistance and XDR-TB by type of testing (indirect versus direct testing).The populations of interest were adults with drug-susceptible TB or drug-resistant TB. The settings of interest were intermediate and central laboratories. SEARCH METHODS: We searched the following databases without any language restriction up to 30 January 2014: Cochrane Infectious Diseases Group Specialized Register; MEDLINE; EMBASE; ISI Web of Knowledge; MEDION; LILACS; BIOSIS; SCOPUS; the metaRegister of Controlled Trials; the search portal of the World Health Organization International Clinical Trials Registry Platform; and ProQuest Dissertations & Theses A&I. SELECTION CRITERIA: We included all studies that determined MTBDRsl accuracy against a defined reference standard (culture-based drug susceptibility testing (DST), genetic testing or both). We included cross-sectional and diagnostic case-control studies. We excluded unpublished data and conference proceedings. DATA COLLECTION AND ANALYSIS: For each study, two review authors independently extracted data using a standardized form and assessed study quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. We performed meta-analyses to estimate the pooled sensitivity and specificity of MTBDRsl for FQ resistance, SLID resistance, and XDR-TB. We explored the influence of different reference standards. We performed the majority of analyses using a bivariate random-effects model against culture-based DST as the reference standard. MAIN RESULTS: We included 21 unique studies: 14 studies reported the accuracy of MTBDRsl when done directly, five studies when done indirectly and two studies that did both. Of the 21 studies, 15 studies (71%) were cross-sectional and 11 studies (58%) were located in low-income or middle-income countries. All studies but two were written in English. Nine (43%) of the 21 included studies had a high risk of bias for patient selection. At least half of the studies had low risk of bias for the other QUADAS-2 domains.As a test for FQ resistance measured against culture-based DST, the pooled sensitivity of MTBDRsl when performed indirectly was 83.1% (95% confidence interval (CI) 78.7% to 86.7%) and the pooled specificity was 97.7% (95% CI 94.3% to 99.1%), respectively (16 studies, 1766 participants; 610 confirmed cases of FQ-resistant TB; moderate quality evidence). When performed directly, the pooled sensitivity was 85.1% (95% CI 71.9% to 92.7%) and the pooled specificity was 98.2% (95% CI 96.8% to 99.0%), respectively (seven studies, 1033 participants; 230 confirmed cases of FQ-resistant TB; moderate quality evidence). For indirect testing for FQ resistance, four (0.2%) of 1766 MTBDRsl results were indeterminate, whereas for direct testing 20 (1.9%) of 1033 were MTBDRsl indeterminate (P < 0.001).As a test for SLID resistance measured against culture-based DST, the pooled sensitivity of MTBDRsl when performed indirectly was 76.9% (95% CI 61.1% to 87.6%) and the pooled specificity was 99.5% (95% CI 97.1% to 99.9%), respectively (14 studies, 1637 participants; 414 confirmed cases of SLID-resistant TB; moderate quality evidence). For amikacin resistance, the pooled sensitivity and specificity were 87.9% (95% CI 82.1% to 92.0%) and 99.5% (95% CI 97.5% to 99.9%), respectively. For kanamycin resistance, the pooled sensitivity and specificity were 66.9% (95% CI 44.1% to 83.8%) and 98.6% (95% CI 96.1% to 99.5%), respectively. For capreomycin resistance, the pooled sensitivity and specificity were 79.5% (95% CI 58.3% to 91.4%) and 95.8% (95% CI 93.4% to 97.3%), respectively. When performed directly, the pooled sensitivity for SLID resistance was 94.4% (95% CI 25.2% to 99.9%) and the pooled specificity was 98.2% (95% CI 88.9% to 99.7%), respectively (six studies, 947 participants; 207 confirmed cases of SLID-resistant TB, 740 SLID susceptible cases of TB; very low quality evidence). For indirect testing for SLID resistance, three (0.4%) of 774 MTBDRsl results were indeterminate, whereas for direct testing 53 (6.1%) of 873 were MTBDRsl indeterminate (P < 0.001).As a test for XDR-TB measured against culture-based DST, the pooled sensitivity of MTBDRsl when performed indirectly was 70.9% (95% CI 42.9% to 88.8%) and the pooled specificity was 98.8% (95% CI 96.1% to 99.6%), respectively (eight studies, 880 participants; 173 confirmed cases of XDR-TB; low quality evidence). AUTHORS' CONCLUSIONS: In adults with TB, a positive MTBDRsl result for FQ resistance, SLID resistance, or XDR-TB can be treated with confidence. However, MTBDRsl does not detect approximately one in five cases of FQ-resistant TB, and does not detect approximately one in four cases of SLID-resistant TB. Of the three SLIDs, MTBDRsl has the poorest sensitivity for kanamycin resistance. MTBDRsl will miss between one in four and one in three cases of XDR-TB. The diagnostic accuracy of MTBDRsl is similar when done using either culture isolates or smear-positive sputum. As the location of the resistance causing mutations can vary on a strain-by-strain basis, further research is required on test accuracy in different settings and, if genetic sequencing is used as a reference standard, it should examine all resistance-determining regions. Given the confidence one can have in a positive result, and the ability of the test to provide results within a matter of days, MTBDRsl may be used as an initial test for second-line drug resistance. However, when the test reports a negative result, clinicians may still wish to carry out conventional testing.


Subject(s)
Antitubercular Agents/therapeutic use , Extensively Drug-Resistant Tuberculosis/diagnosis , Microbial Sensitivity Tests/methods , Mycobacterium tuberculosis/drug effects , Adult , Cross-Sectional Studies , Extensively Drug-Resistant Tuberculosis/drug therapy , Fluoroquinolones/therapeutic use , Genotype , Humans , Microbial Sensitivity Tests/standards , Sensitivity and Specificity
SELECTION OF CITATIONS
SEARCH DETAIL