Barriers and facilitators to tuberculosis diagnosis in Lima, Peru: a mixed methods study.

BACKGROUND: Tuberculosis (TB) infectiousness decreases significantly with only a few days of treatment, but delayed diagnosis often leads to late treatment initiation. We conducted a sequential explanatory mixed methods study to understand the barriers and facilitators to prompt diagnosis among people with TB. METHODS: We enrolled 100 adults who started TB treatment in the Carabayllo district of Lima, Peru, between November 2020 and February 2022 and administered a survey about their symptoms and healthcare encounters. We calculated total diagnostic delay as time from symptom onset to diagnosis. We conducted semi-structured interviews of 26 participants who had a range of delays investigating their experience navigating the health system. Interview transcripts were inductively coded for concepts related to diagnostic barriers and facilitators. RESULTS: Overall, 38% of participants sought care first from public facilities and 42% from the private sector. Only 14% reported being diagnosed with TB on their first visit, and participants visited a median of 3 (interquartile range [IQR] health facilities before diagnosis. The median total diagnostic delay was 9 weeks (interquartile range [IQR] 4-22), with a median of 4 weeks (IQR 0-9) before contact with the health system and of 3 weeks (IQR 0-9) after. Barriers to prompt diagnosis included participants attributing their symptoms to an alternative cause or having misconceptions about TB, and leading them to postpone seeking care. Once connected to care, variations in clinical management, health facility resource limitations, and lack of formal referral processes contributed to the need for multiple healthcare visits before obtaining a diagnosis. Facilitators to prompt diagnosis included knowing someone with TB, supportive friends and family, referral documents, and seeing a pulmonologist. CONCLUSIONS: Misinformation about TB among people with TB and providers, poor accessibility of health services, and the need for multiple encounters to obtain diagnostic tests were major factors leading to delays. Extending the hours of operation of public health facilities, improving community awareness and provider training, and creating a formal referral process between the public and private sectors should be priorities in the efforts to combat TB.

Utility of Mycobacterium tuberculosis genome sequencing snapshots to assess transmission dynamics over time.

We explored the utility of brief Mycobacterium tuberculosis whole-genome sequencing (WGS) "snapshots" at a sentinel site within Lima, Peru for evaluating local transmission dynamics over time. Within a 17 km2 area, 15/70 (21%) isolates with WGS collected during 2011-2012 and 22/81 (27%) collected during 2020-2021 were clustered (p = 0.414), and additional isolates clustered with those from outside the area. Isolates from the later period were disproportionately related to large historic clusters in Lima from the earlier period. WGS snapshots at a sentinel site may not be useful for monitoring transmission, but monitoring the persistence of large transmission clusters might be.

Sensitivity of Various Case Detection Algorithms for Community-based Tuberculosis Screening.

Using data from 388 people diagnosed with tuberculosis through a community-based screening program in Lima, Peru, we estimated that cough screening followed by sputum smear microscopy would have detected only 23% of cases found using an algorithm of radiographic screening followed by rapid nucleic acid amplification testing and clinical evaluation.

Tuberculosis care models for children and adolescents: a scoping review.

Objective: To map which tuberculosis care models are best suited for children and adolescents. Methods: We conducted a scoping review to assess the impact of decentralized, integrated and family-centred care on child and adolescent tuberculosis-related outcomes, describe approaches for these care models and identify key knowledge gaps. We searched seven literature databases on 5 February 2021 (updated 16 February 2022), searched the references of 18 published reviews and requested data from ongoing studies. We included studies from countries with a high tuberculosis burden that used a care model of interest and reported tuberculosis diagnostic, treatment or prevention outcomes for an age group < 20 years old. Findings: We identified 28 studies with a comparator group for the impact assessment and added 19 non-comparative studies to a qualitative analysis of care delivery approaches. Approaches included strengthening capacity in primary-level facilities, providing services in communities, screening for tuberculosis in other health services, co-locating tuberculosis and human immunodeficiency virus treatment, offering a choice of treatment location and providing social or economic support. Strengthening both decentralized diagnostic services and community linkages led to one-to-sevenfold increases in case detection across nine studies and improved prevention outcomes. We identified only five comparative studies on integrated or family-centred care, but 11 non-comparative studies reported successful treatment outcomes for at least 71% of children and adolescents. Conclusion: Strengthening decentralized services in facilities and communities can improve tuberculosis outcomes for children and adolescents. Further research is needed to identify optimal integrated and family-centred care approaches.

The impact of the COVID-19 pandemic on patients' experiences obtaining a tuberculosis diagnosis in Peru: a mixed-methods study.

BACKGROUND: The COVID-19 pandemic disrupted TB services worldwide, leading to diagnostic delays. There have been few published reports describing how the pandemic affected people's pathway to diagnosis from their own perspectives. We sought to evaluate the impact on the pandemic on people's experiences obtaining a TB diagnosis. METHODS: We performed a mixed-methods study, enrolling newly diagnosed TB patients from 12 health centers in Lima, Peru. We used structured surveys to quantify diagnostic delay, defined as the time between symptom onset and diagnosis, and in-depth interviews to understand the ways in which the pandemic affected the pathway to care. We compared diagnostic delay between patients enrolled during the first year of the pandemic to those diagnosed after using a Wilcoxon rank-sum test. We used an inductive content analysis approach to analyze interview content related to the pandemic. RESULTS: We enrolled 51 patients during November 2020-April 2021 (during the first year of the pandemic) and 49 patients during October 2021-February 2022. Median diagnostic delay was longer for patients diagnosed during the first year of the pandemic (median 15 [IQR 5-26] weeks compared to 6 [IQR 3-18] weeks, p = 0.027). Qualitative analysis of 26 interviews revealed that the pandemic affected participants' care-seeking behavior and their ability to access to TB diagnostic services, particularly for those diagnosed in the first year of the pandemic. Many participants initially had their symptoms attributed to COVID-19, resulting in delayed TB evaluation and additional costs for COVID-19 treatment. CONCLUSIONS: The COVID-19 pandemic impacted multiple steps in the pathway to care for TB patients in Lima, causing delays in TB diagnosis. These findings demonstrate how the shifting of health care resources to prioritize COVID-19 can lead to collateral damage for people with TB and other conditions.

Concordance of Drug-resistance Profiles Between Persons With Drug-resistant Tuberculosis and Their Household Contacts: A Systematic Review and Meta-analysis.

BACKGROUND: Household contacts of patients with drug-resistant tuberculosis (TB) are at high risk for being infected with Mycobacterium tuberculosis and for developing TB disease. To guide regimen composition for the empirical treatment of TB infection and disease in these household contacts, we estimated drug-resistance profile concordance between index patients with drug-resistant TB and their household contacts. METHODS: We performed a systematic review and meta-analysis of studies published through 24 July 2018 that reported resistance profiles of drug-resistant TB index cases and secondary cases within their households. Using a random-effects meta-analysis, we estimated resistance profile concordance, defined as the percentage of secondary cases whose M. tuberculosis strains were resistant to the same drugs as strains from their index cases. We also estimated isoniazid/rifampin concordance, defined as whether index and secondary cases had identical susceptibilities for isoniazid and rifampin only. RESULTS: We identified 33 eligible studies that evaluated resistance profile concordance between 484 secondary cases and their household index cases. Pooled resistance profile concordance was 54.3% (95% confidence interval [CI], 40.7-67.6%; I2 = 85%). Pooled isoniazid/rifampin concordance was 82.6% (95% CI, 72.3-90.9%; I2 = 73%). Concordance estimates were similar in a subanalysis of 16 studies from high-TB-burden countries. There were insufficient data to perform a subanalysis among pediatric secondary cases. CONCLUSIONS: Household contacts of patients with drug-resistant TB should receive treatment for TB infection and disease that assumes that they, too, are infected with a drug-resistant M. tuberculosis strain. Whenever possible, drug susceptibility testing should be performed for secondary cases to optimize regimen composition.

Cost of Delivering 12-Dose Isoniazid and Rifapentine Versus 6 Months of Isoniazid for Tuberculosis Infection in a High-Burden Setting.

BACKGROUND: Successful delivery and completion of tuberculosis preventive treatment are necessary for tuberculosis elimination. Shorter preventive treatment regimens currently have higher medication costs, but patients spend less time in care and are more likely to complete treatment. It is unknown how economic costs of successful delivery differ between longer and shorter regimens in high-tuberculosis-burden settings. METHODS: We developed survey instruments to collect costs from program and patient sources, considering costs incurred from when household contacts first entered the health system. We compared the cost per completed course of preventive treatment with either 6 months of daily isoniazid (6H) or 3 months of weekly isoniazid and rifapentine (3HP), delivered by the Indus Health Network tuberculosis program in Karachi, Pakistan, between October 2016 and February 2018. RESULTS: During this period, 459 individuals initiated 6H and 643 initiated 3HP; 39% and 61% completed treatment, respectively. Considering costs to both the program and care recipients, the cost per completed course was 394 US dollars (USD) for 6H and 333 USD for 3HP. Using a new 2020 price for rifapentine reduced the cost per completed course of 3HP to 290 USD. Under varying assumptions about drug prices and costs incurred by care recipients, the cost per completed course was lower for 3HP in all scenarios, and the largest cost drivers were the salaries of clinical staff. CONCLUSIONS: In a high-burden setting, the cost of successful delivery of 3HP was lower than that of 6H, driven by higher completion.

Toward patient-centered tuberculosis preventive treatment: preferences for regimens and formulations in Lima, Peru.

BACKGROUND: To ensure patient-centered tuberculosis preventive treatment, it is important to consider factors that make it easier for patients to complete treatment. However, there is little published literature about patient preferences for different preventive treatment regimen options, particularly from countries with high tuberculosis burdens. METHODS: We conducted a qualitative research study using a framework analysis approach to understand tuberculosis preventive treatment preferences among household contacts. We conducted three focus group discussions with 16 members of families affected by tuberculosis in Lima, Peru. Participants were asked to vote for preferred preventive treatment regimens and discuss the reasons behind their choices. Coding followed a deductive approach based on prior research, with data-driven codes added. RESULTS: In total, 7 (44%) participants voted for 3 months isoniazid and rifapentine, 4 (25%) chose 3 months isoniazid and rifampicin, 3 (19%) chose 4 months rifampicin, and 2 (13%) chose 6 months isoniazid. Preferences for shorter regimens over 6 months of isoniazid were driven by concerns over "getting tired" or "getting bored" of taking medications, the difficulty of remembering to take medications, side effects, and interference with daily life. For some, weekly dosing was perceived as being easier to remember and less disruptive, leading to a preference for 3 months isoniazid and rifapentine, which is dosed weekly. However, among caregivers, having a child-friendly formulation was more important than regimen duration. Caregivers reported difficulty in administering pills to children, and preferred treatments available as syrup or dispersible formulations. CONCLUSIONS: There is demand for shorter regimens and child-friendly formulations for tuberculosis preventive treatment in high-burden settings. Individual preferences differ, suggesting that patient-centered care would best be supported by having multiple shorter regimens available.

Tuberculosis Preventive Therapy for Individuals Exposed to Drug-resistant Tuberculosis: Feasibility and Safety of a Community-based Delivery of Fluoroquinolone-containing Preventive Regimen.

BACKGROUND: Observational studies have demonstrated the effectiveness of a fluoroquinolone-based regimen to treat individuals presumed to be infected with drug-resistant tuberculosis (DR-TB). We sought to assess the feasibility of this approach in an urban setting in South Asia. METHODS: From February 2016 until March 2017, all household contacts of DR-TB patients enrolled at the Indus Hospital were screened for TB symptoms at home. Children aged 0-17 years, symptomatic adults, and those with an immunocompromising condition (human immunodeficiency virus, diabetes, or malnutrition) were evaluated for TB disease. Contacts diagnosed with TB disease were started on treatment. Contacts without TB disease aged <5 years, contacts aged between 5 and 17 years with either a positive tuberculin skin test or an immunocompromising condition, or contacts aged ≥18 years with an immunocompromising condition were offered 6 months of treatment with a fluoroquinolone. RESULTS: One hundred households with 800 contacts were enrolled: 353 (44.1%) individuals aged ≤17 years with a median age of 19 years (interquartile range, 10-32); 423 (52.9%) were males. In total, 737 (92.1%) individuals were screened, of which 8 were already on treatment for TB (1.1%); another 3 (0.4%) contacts were diagnosed with TB disease and started on treatment. Of 215 eligible for infection treatment, 172 (80.0%) contacts initiated and 121 (70.3%) completed treatment. No TB disease or significant adverse events were observed during 12 months of follow-up. CONCLUSIONS: Fluoroquinolone-based treatment for contacts with presumed DR-TB infection is feasible and well tolerated in a high TB burden setting.

Tuberculosis disease and infection among household contacts of bacteriologically confirmed and non-confirmed tuberculosis patients.

OBJECTIVE: To compare the prevalence of tuberculosis infection and disease in household contacts of patients with bacteriologically confirmed tuberculosis disease and contacts of non-bacteriologically confirmed disease in western Kenya. METHODS: We enrolled newly diagnosed index patients and their household contacts from March 2014 to June 2016. All contacts were evaluated with a symptom questionnaire, tuberculin skin test (TST) and HIV test. Clinical evaluation and sputum testing were performed for those with symptoms, positive TST result or HIV infection. RESULTS: We enrolled 1155 contacts of 330 index patients with bacteriologically confirmed tuberculosis and 192 contacts of 55 index patients with non-bacteriologically confirmed tuberculosis. 3.5% of contacts of patients with bacteriologically confirmed tuberculosis were diagnosed with tuberculosis, whereas no contacts of index patients with non-bacteriologically confirmed tuberculosis were. Of those diagnosed with tuberculosis disease, 58.5% reported symptoms, 34.1% reported no symptoms but had positive TST results, and 7.3% had neither symptoms nor positive TST but were HIV-positive. Among 872 contacts with a TST result, 50.9% of contacts of index patients with bacteriologically confirmed tuberculosis and 41.0% of contacts of index patients with non-bacteriologically confirmed tuberculosis had a positive result (prevalence ratio = 1.16, 95% confidence interval 0.92-1.48). CONCLUSION: In a high-burden setting, tuberculosis disease was more prevalent among contacts of patients with bacteriologically confirmed tuberculosis than contacts of patients with non-bacteriologically confirmed disease. TST was feasible to perform and helped to detect cases that would have been missed had only symptomatic contacts been evaluated.

OBJECTIF: Comparer la prévalence de l'infection et de la maladie tuberculeuses chez les contacts familiaux des patients atteints de tuberculose confirmée bactériologiquement et les contacts de maladies non bactériologiquement confirmées dans l'ouest du Kenya. MÉTHODES: Nous avons recruté des patients indice nouvellement diagnostiqués et leurs contacts familiaux de mars 2014 à juin 2016. Tous les contacts ont été évalués à l'aide d'un questionnaire sur les symptômes, le test cutané à la tuberculine (TCT) et le test VIH. Une évaluation clinique et des tests d'expectoration ont été effectués pour les personnes présentant des symptômes, un résultat positif au TCT ou une infection par le VIH. RÉSULTATS: Nous avons recruté 1.155 contacts de 330 patients index avec une tuberculose confirmée bactériologiquement et 192 contacts de 55 patients indice avec une tuberculose non confirmée bactériologiquement. 3,5% des contacts des patients atteints de tuberculose confirmée bactériologiquement ont été diagnostiqués avec la tuberculose, alors qu'aucun contact des patients indice avec une tuberculose non bactériologiquement confirmée ne l'a été. Parmi les personnes diagnostiquées avec une tuberculose, 58,5% ont signalé des symptômes, 34,1% n'ont signalé aucun symptôme mais avaient des résultats positifs au TCT, et 7,3% n'avaient ni symptômes ni TCT positifs mais étaient VIH positifs. Parmi 872 contacts avec un résultat TCT, 50,9% des contacts des patients indice avec une tuberculose confirmée bactériologiquement et 41,0% des contacts des patients indice avec une tuberculose non bactériologiquement confirmée avaient un résultat positif (rapport de prévalence = 1,16, intervalle de confiance à 95%: 0,92-1,48 ). CONCLUSION: Dans un contexte de charge élevée, la maladie tuberculose était plus fréquente chez les contacts des patients atteints de tuberculose confirmée bactériologiquement que chez les contacts des patients atteints de la maladie non bactériologiquement confirmée. Le TCT était réalisable et a aidé à détecter les cas qui auraient été ratés si seuls les contacts symptomatiques avaient été évalués.

Building Emotional Resilience in Youth in Lebanon: a School-Based Randomized Controlled Trial of the FRIENDS Intervention.

In Lebanon, approximately one in four adolescents suffers from a psychiatric disorder. Alarmingly, 94% of adolescents with a mental disorder have not sought any treatment. This study assessed the effectiveness of an evidence-based school-based universal mental health intervention (the FRIENDS program) in reducing depression and anxiety symptoms in middle school students in Lebanon. A total of 280 6th graders aged 11-13 years were recruited from 10 schools in Beirut. Schools were matched on size and tuition and randomly assigned to intervention or control groups. The FRIENDS program was translated into Arabic, adapted, and then implemented by trained mental health professionals during 10 classroom sessions over 3 months. We assessed sociodemographic and relevant psychological symptoms by self-report, using the Scale for Childhood Anxiety and Related Disorders (SCARED), Mood and Feelings Questionnaire (MFQ), and Strengths and Difficulties Questionnaire (SDQ), at baseline. We re-administered these scales at 3 months post-intervention. There was a significant time × group interaction for the SDQ emotional score (p = 0.011) and total MFQ score (p = 0.039) indicating significant improvement in depressive and emotional symptoms in the intervention group. Subgroup analysis by gender showed a significant time × group interaction for the total SCARED score (p = 0.025) in females but not in males (p = 0.137), consistent with a reduction of anxiety symptoms in this stratum of the intervention group as compared with the control group. The FRIENDS program was effective in reducing general emotional and depressive symptoms among middle school students in this Lebanese study population. This intervention provides an opportunity for promoting mental health in Lebanese schools and reducing the treatment gap in mental health care.

Development and Evaluation of a Mental Health Training Program for Community Health Workers in Indonesia.

The treatment gap in mental health care in Indonesia is a critical issue due in large measure to the dearth of professional mental health staff. In response to this need, our team designed a mental health training program for existing community health workers. The training program was offered to 65 participants at 2 (two) community primary care center (Puskesmas); we evaluated the training program with quantitative and qualitative methods. We assessed the gains in knowledge using a 20-question knowledge assessment test. In addition, in Puskesmas 1, the test was repeated as a follow-up test 4 months after the training. Statistical analysis showed that the differences between pre-test and post-test scores were significant in both Puskesmas 1 (p = 0.004) and Puskesmas 2 (p < 0.001). This study concluded that the model of integrative training appears effective for preparing Indonesian CHWs to recognize and respond to needs for mental health care.

Pharmacokinetics of Levofloxacin in Children Treated for Exposure to Drug-Resistant Tuberculosis.

Levofloxacin is used to treat and prevent drug-resistant tuberculosis in children. We assessed levofloxacin serum drug concentrations in 24 children aged 2 to 10 years who received levofloxacin-based tuberculosis preventive therapy in Karachi, Pakistan. Only 9 children (37.5%) achieved adequate drug exposure. Target serum drug concentration was met in 4 (26.7%) of 15 children dosed consistently with World Health Organization recommendations and 4 (80.0%) of 5 who received higher-than-recommended doses. Levofloxacin dosing recommendations may require reevaluation.

Epidemiology of Pediatric Tuberculosis in Kenya and Risk Factors for Mortality during Treatment: A National Retrospective Cohort Study.

OBJECTIVES: To describe the epidemiology of childhood tuberculosis (TB) in Kenya, assess the magnitude of TB/human immunodeficiency virus (HIV) co-infection and identify risk factors for mortality during TB treatment. STUDY DESIGN: We conducted a retrospective analysis of the Kenyan national TB program data for patients enrolled from 2013 through 2015. A total of 23 753 children aged less than 15 years were included in the analysis. Survival analysis was performed with censorship at 9 months and mortality was the main outcome. We used Cox proportional hazards regression for assessing risk factors for mortality. RESULTS: Childhood TB accounted for 9% (n = 24 216) of all patients with TB; 98% of the notified children (n = 23 753) were included in the analysis. TB/HIV co-infection was 28% (n = 6112). Most TB cases (71%; n = 16 969) were detected through self-referral. Treatment was successful in 90% (n = 19 088) and 4% (n = 1058) died. Independent risk factors for mortality included being HIV infected but not on antiretroviral therapy (adjusted hazard ratio [aHR], 4.84; 95% CI, 3.59-6.51), being HIV infected and on antiretroviral therapy (aHR, 3.69; 95% CI, 3.14-4.35), children aged less than 5 years (aHR, 1.25; 95% CI, 1.08-1.44), and being diagnosed with smear negative pulmonary disease (aHR, 1.68; 95% CI, 1.27-2.24). CONCLUSIONS: Most childhood TB cases in Kenya were detected through passive case finding. TB/HIV co-infection is high among children on treatment for TB, and HIV is associated with an increased risk of death. There is a need to intensify active case finding among children. TB prevention interventions among HIV-infected children, early diagnosis of HIV, and early antiretroviral therapy initiation among children on TB treatment should be strengthened.

Assessing the impact of antiretroviral therapy on tuberculosis notification rates among people with HIV: a descriptive analysis of 23 countries in sub-Saharan Africa, 2010-2015.

BACKGROUND: HIV is a major driver of the tuberculosis epidemic in sub-Saharan Africa. The population-level impact of antiretroviral therapy (ART) scale-up on tuberculosis rates in this region has not been well studied. We conducted a descriptive analysis to examine evidence of population-level effect of ART on tuberculosis by comparing trends in estimated tuberculosis notification rates, by HIV status, for countries in sub-Saharan Africa. METHODS: We estimated annual tuberculosis notification rates, stratified by HIV status during 2010-2015 using data from WHO, the Joint United Nations Programme on HIV/AIDS, and the United Nations Population Division. Countries were included in this analysis if they had ≥4 years of HIV prevalence estimates and ≥ 75% of tuberculosis patients with known HIV status. We compared tuberculosis notification rates among people living with HIV (PLHIV) and people without HIV via Wilcoxon rank sum test. RESULTS: Among 23 included countries, the median annual average change in tuberculosis notification rates among PLHIV during 2010-2015 was -5.7% (IQR -6.9 to -1.7%), compared to a median change of -2.3% (IQR -4.2 to -0.1%) among people without HIV (p-value = 0.0099). Among 11 countries with higher ART coverage, the median annual average change in TB notification rates among PLHIV was -6.8% (IQR -7.6 to -5.7%) compared to a median change of -2.1% (IQR -6.0 to 0.7%) for PLHIV in 12 countries with lower ART coverage (p = 0.0106). CONCLUSION: Tuberculosis notification rates declined more among PLHIV than people without HIV, and have declined more in countries with higher ART coverage. These results are consistent with a population-level effect of ART on decreasing TB incidence among PLHIV. To further reduce TB incidence among PLHIV, additional scale-up of ART as well as greater use of isoniazid preventive therapy and active case-finding will be necessary.

Addressing tuberculosis patients' medical and socio-economic needs: a comprehensive programmatic approach.

OBJECTIVE: For a cohort of patients with tuberculosis in Carabayllo, Peru, we describe the prevalence of medical comorbidities and socio-economic needs, the efforts required by a comprehensive support programme ('TB Cero') to address them and the success of this programme in linking patients to care. METHODS: Patients diagnosed with tuberculosis in Carabayllo underwent evaluations for HIV, diabetes, mental health and unmet basic needs. For patients initiating treatment during 14 September, 2015-15 May, 2016, we abstracted data from evaluation forms and a support request system. We calculated the prevalence of medical comorbidities and the need for socio-economic support at the time of tuberculosis diagnosis, as well as the proportion of patients successfully linked to care or support. RESULTS: Of 192 patients, 83 (43%) had at least one medical comorbidity other than tuberculosis. These included eight (4%) patients with HIV, 12 (6%) with diabetes and 62 (32%) deemed at risk for a mental health condition. Of patients who required follow-up for a comorbidity, 100% initiated antiretroviral therapy, 71% attended endocrinology consultations and 66% attended psychology consultations. Of 126 (65%) patients who completed the socio-economic evaluation, 58 (46%) reported already receiving food baskets from the municipality, and 79 (63%) were given additional support, most commonly food vouchers and assistance in accessing health care. CONCLUSION: Carabayllo tuberculosis patients face many challenges in addition to tuberculosis. A collaborative, comprehensive treatment support programme can achieve high rates of linkage to care for these needs.

Turning off the tap: stopping tuberculosis transmission through active case-finding and prompt effective treatment.

To halt the global tuberculosis epidemic, transmission must be stopped to prevent new infections and new cases. Identification of individuals with tuberculosis and prompt initiation of effective treatment to rapidly render them non-infectious is crucial to this task. However, in settings of high tuberculosis burden, active case-finding is often not implemented, resulting in long delays in diagnosis and treatment. A range of strategies to find cases and ensure prompt and correct treatment have been shown to be effective in high tuberculosis-burden settings. The population-level effect of targeted active case-finding on reducing tuberculosis incidence has been shown by studies and projected by mathematical modelling. The inclusion of targeted active case-finding in a comprehensive epidemic-control strategy for tuberculosis should contribute substantially to a decrease in tuberculosis incidence.

Association between Regimen Composition and Treatment Response in Patients with Multidrug-Resistant Tuberculosis: A Prospective Cohort Study.

BACKGROUND: For treating multidrug-resistant tuberculosis (MDR TB), the World Health Organization (WHO) recommends a regimen of at least four second-line drugs that are likely to be effective as well as pyrazinamide. WHO guidelines indicate only marginal benefit for regimens based directly on drug susceptibility testing (DST) results. Recent evidence from isolated cohorts suggests that regimens containing more drugs may be beneficial, and that DST results are predictive of regimen effectiveness. The objective of our study was to gain insight into how regimen design affects treatment response by analyzing the association between time to sputum culture conversion and both the number of potentially effective drugs included in a regimen and the DST results of the drugs in the regimen. METHODS AND FINDINGS: We analyzed data from the Preserving Effective Tuberculosis Treatment Study (PETTS), a prospective observational study of 1,659 adults treated for MDR TB during 2005-2010 in nine countries: Estonia, Latvia, Peru, Philippines, Russian Federation, South Africa, South Korea, Thailand, and Taiwan. For all patients, monthly sputum samples were collected, and DST was performed on baseline isolates at the US Centers for Disease Control and Prevention. We included 1,137 patients in our analysis based on their having known baseline DST results for at least fluoroquinolones and second-line injectable drugs, and not having extensively drug-resistant TB. These patients were followed for a median of 20 mo (interquartile range 16-23 mo) after MDR TB treatment initiation. The primary outcome of interest was initial sputum culture conversion. We used Cox proportional hazards regression, stratifying by country to control for setting-associated confounders, and adjusting for the number of drugs to which patients' baseline isolates were resistant, baseline resistance pattern, previous treatment history, sputum smear result, and extent of disease on chest radiograph. In multivariable analysis, receiving an average of at least six potentially effective drugs (defined as drugs without a DST result indicating resistance) per day was associated with a 36% greater likelihood of sputum culture conversion than receiving an average of at least five but fewer than six potentially effective drugs per day (adjusted hazard ratio [aHR] 1.36, 95% CI 1.09-1.69). Inclusion of pyrazinamide (aHR 2.00, 95% CI 1.65-2.41) or more drugs to which baseline DST indicated susceptibility (aHR 1.65, 95% CI 1.48-1.84, per drug) in regimens was associated with greater increases in the likelihood of sputum culture conversion than including more drugs to which baseline DST indicated resistance (aHR 1.33, 95% CI 1.18-1.51, per drug). Including in the regimen more drugs for which DST was not performed was beneficial only if a minimum of three effective drugs was present in the regimen (aHR 1.39, 95% CI 1.09-1.76, per drug when three effective drugs present in regimen). The main limitation of this analysis is that it is based on observational data, not a randomized trial, and drug regimens varied across sites. However, PETTS was a uniquely large and rigorous observational study in terms of both the number of patients enrolled and the standardization of laboratory testing. Other limitations include the assumption of equivalent efficacy across drugs in a category, incomplete data on adherence, and the fact that the analysis considers only initial sputum culture conversion, not reversion or long-term relapse. CONCLUSIONS: MDR TB regimens including more potentially effective drugs than the minimum of five currently recommended by WHO may encourage improved response to treatment in patients with MDR TB. Rapid access to high-quality DST results could facilitate the design of more effective individualized regimens. Randomized controlled trials are necessary to confirm whether individualized regimens with more than five drugs can indeed achieve better cure rates than current recommended regimens.

Incidence of multidrug-resistant tuberculosis disease in children: systematic review and global estimates.

BACKGROUND: Multidrug-resistant tuberculosis threatens to reverse recent reductions in global tuberculosis incidence. Although children younger than 15 years constitute more than 25% of the worldwide population, the global incidence of multidrug-resistant tuberculosis disease in children has never been quantified. We aimed to estimate the regional and global annual incidence of multidrug-resistant tuberculosis in children. METHODS: We developed two models: one to estimate the setting-specific risk of multidrug-resistant tuberculosis among child cases of tuberculosis, and a second to estimate the setting-specific incidence of tuberculosis disease in children. The model for risk of multidrug-resistant tuberculosis among children with tuberculosis needed a systematic literature review. We multiplied the setting-specific estimates of multidrug-resistant tuberculosis risk and tuberculosis incidence to estimate regional and global incidence of multidrug-resistant tuberculosis disease in children in 2010. FINDINGS: We identified 3403 papers, of which 97 studies met inclusion criteria for the systematic review of risk of multidrug-resistant tuberculosis. 31 studies reported the risk of multidrug-resistant tuberculosis in both children and treatment-naive adults with tuberculosis and were used for evaluation of the linear association between multidrug-resistant disease risk in these two patient groups. We identified that the setting-specific risk of multidrug-resistant tuberculosis was nearly identical in children and treatment-naive adults with tuberculosis, consistent with the assertion that multidrug-resistant disease in both groups reflects the local risk of transmitted multidrug-resistant tuberculosis. After application of these calculated risks, we estimated that around 999,792 (95% CI 937,877-1,055,414) children developed tuberculosis disease in 2010, of whom 31,948 (25,594-38,663) had multidrug-resistant disease. INTERPRETATION: Our estimates underscore that many cases of tuberculosis and multidrug-resistant tuberculosis disease are not being detected in children. Future estimates can be refined as more and better tuberculosis data and new diagnostic instruments become available. FUNDING: US National Institutes of Health, the Helmut Wolfgang Schumann Fellowship in Preventive Medicine at Harvard Medical School, the Norman E Zinberg Fellowship at Harvard Medical School, and the Doris and Howard Hiatt Residency in Global Health Equity and Internal Medicine at the Brigham and Women's Hospital.

Yield of contact investigations in households of patients with drug-resistant tuberculosis: systematic review and meta-analysis.

Contact investigations among individuals living with drug-susceptible tuberculosis patients (source cases) have shown a high yield of tuberculosis disease and latent tuberculosis, but the yield of such investigations in households of drug-resistant tuberculosis source cases is unknown. In this systematic review and meta-analysis, we found 25 studies that evaluated a median of 111 (interquartile range, 21-302) household contacts of drug-resistant tuberculosis source cases. The pooled yield was 7.8% (95% CI, 5.6%-10.0%) for active tuberculosis and 47.2% (95% CI, 30.0%-61.4%) for latent tuberculosis, although there was significant statistical heterogeneity (P < .0001). More than 50% of secondary cases with drug susceptibility test results were concordant with those of the source case. Among studies that followed household members, the majority of secondary cases were detected within 1 year of the source case's diagnosis. Household contact investigation around drug-resistant tuberculosis patients is a high-yield intervention for detection of drug-resistant tuberculosis and prevention of ongoing transmission.