Diagnostic and treatment delays of multidrug-resistant tuberculosis before initiating treatment: a cross-sectional study

To investigate the impact of revised diagnostic algorithm on presentation of multidrug-resistant tuberculosis cases at a referral centre in India

Introduction

A shift in policy has occurred with the introduction of molecular diagnostic tools for the upfront diagnosis of all cases of tuberculosis, including drug-resistant tuberculosis. The impact of this shift in policy on severity of disease was studied, and comparisons were drawn between the year 2015 and 2020.

Study Type and Design

This was an observational study conducted between 2020 and 2021. Seventy patients of MDR-TB with or without additional drug resistance, hospitalized in the year 2015 and 2020, were studied.

Results

The study reveals a substantial reduction in the median time from the onset of symptoms to diagnosis between 2015 and 2020. Specifically, the median duration decreased from 12 weeks in 2015 to 8 weeks in 2020. Moreover, we found that in 2015, all cases under study had a history of tuberculosis in comparison to 2020. Additionally, there was a higher incidence of anemia in 2015 compared to 2020. In the radiological examination, it was observed that in 2015, a higher frequency of cases exhibited cavitations, bronchiectasis, and fibrosis on chest X-rays compared to the findings in 2020. The mean cavity size in 2015 measured 6.73 cm, while in 2020, it averaged 4.06 cm. Additionally, we noticed a higher occurrence of significantly advanced cases in 2015 in contrast to 2020.

Conclusion

The implementation of the new policy of upfront DST was noted to decrease the time required for diagnosis and bacterial load as ascertained from degree of sputum smear positivity, radiological lesions, and severity of anemia.

Healthcare seeking behavior and delays in case of Drug-Resistant Tuberculosis patients in Bangladesh: Findings from a cross-sectional survey

The emergence of Drug-Resistant Tuberculosis (DR-TB) has become a major threat globally and Bangladesh is no exception. Delays in healthcare seeking, proper diagnosis and initiation of treatment cause continuous transmission of the resistant tubercule bacilli through the communities. This study aimed to assess the different health care-seeking behaviors and delays among DR-TB patients in Bangladesh. A prospective cross-sectional study was conducted from November to December 2018, among 92 culture positive and registered DR-TB patients in four selected hospitals in Bangladesh. Data were collected through face-to-face interviews with survey questionnaire as well as record reviews. Among the 92 study participants, the median patient delay was 7 (IQR 3, 15) days, the median diagnostic delay was 88 (IQR 36.5, 210), the median treatment delay was 7 (IQR 4,12) days, and the median total delay among DR-TB patients was 108.5 (IQR 57.5, 238) days. 81.32% sought initial care from informal healthcare providers. The majority (68.48%) of the informal healthcare providers were drug sellers while 60.87% of patients sought care from more than four healthcare points before being diagnosed with DR-TB. The initial care seeking from multiple providers was associated with diagnostic and total delays. In Bangladesh, DR-TB cases usually seek care from multiple providers, particularly from informal providers, and among them, alarmingly higher healthcare-seeking related delays were noted. Immediate measures should be taken both at the health system levels and, in the community, to curb transmission and reduce the burden of the disease.

Analysis of Drug-Resistant Tuberculosis in Children in Shenyang, China, 2017-2021

Objective

Drug-resistant tuberculosis (DR-TB) in children seriously threatens TB control. Information on the epidemiology and characteristics of DR-TB in children in China is limited. We studied data in Shenyang Tenth People's Hospital to understand the DR-TB epidemiology in children in Shenyang.

Design or Methods

We retrospectively analyzed drug resistance testing data of pediatric TB patients between 2017 and 2021, and included 2976 clinically-diagnosed pediatric TB patients. We described the epidemiology of DR-TB and analyzed the trends of DR-TB incidence. The Kappa value was calculated to assess the agreement between MGIT 960 DST and Xpert MTB/RIF for detecting rifampicin resistance. Multivariate logistic regression was used to identify the risk factors for DR-TB in pediatric patients.

Results

Of the 2976 TB patients, 1076 were confirmed by MGIT 960 culture and/or Xpert MTB/RIF. Among the 806 patients identified by MGIT 960 culture, 232 cases (28.78%) were DR-TB. Resistance to the six drugs was in the following order: streptomycin (21.09%), isoniazid (9.35%), rifampin (15.01%), levofloxacin (6.20%), ethambutol (4.22%), and amikacin (3.23%). Alarmingly, 12.90% were MDR-TB (104/806), including 28 (3.47%) pre-XDR-TB. Of the 1076 pediatric TB patients, 295 (27.4%) developed DR-TB to any one drug (including 69 rifampicin-resistant cases identified by Xpert MTB/RIF only). No difference was found in the incidence of pediatric DR-TB between 2017 and 2021. Among 376 patients who were positive for both methods, using the MGIT 960 DST results as the gold standard, Xpert MTB/RIF's sensitivity for detecting rifampicin resistance was 91.38% and its specificity was 94.65%.

Conclusion

Between 2017 and 2021, the DR-TB incidence in children remained unchanged in Shenyang. RR-TB, MDR-TB, and even Pre-XDR-TB require attention in children with drug-resistant TB. Xpert MTB/RIF helped to detect more rifampicin-resistant pediatric patients; thus Xpert MTB/RIF should be widely used as an important complementary tool to detect rifampicin-resistant TB in children.

Diagnosis and Treatment Pathway of MDR/RR-TB in Taizhou, Zhejiang Province, China

This study aims to understand MDR/RR-TB patients' experience from seeking TB-related health care to diagnosis and treatment completion, as well as the social determinants with the waiting time for DST and treatment, pre-treatment attrition, and treatment outcome based on a retrospective cohort study. Univariate and multi-variate logistic regressions were used to analyze the associated factors. The median time of waiting time for DST and treatment was 24.00 and 30.00 days, respectively. Non-residential patients (aOR: 2.89, 95% CI: 1.14-7.70), registered before 2018 (aOR: 19.93, 95% CI: 8.99-48.51), first visited a county-level hospital (aOR: 4.65, 95% CI: 1.08-21.67), sputum smear-negative (aOR: 3.54, 95% CI: 1.28-10.16), and comorbid with pneumoconiosis (aOR: 7.10, 95% CI: 1.23-47.98) had a longer DST delay. The pre-treatment attrition was 26.9% (82/305). Elderly, non-residential patients and patients registered before 2018 were more likely to refuse MDR/RR treatment. However, in housekeeping/unemployment and farmer/fisherman, recurrent patients tended to take therapeutic measures actively. The successful treatment rate was 62.1% (105/169). Elderly, comorbidity with diabetes and sputum smear conversion time >1 month may lead to poorer outcomes. Immediate interventions should be taken to smooth diagnosis and treatment pathways and improve the social protections further so as to encourage patients to cooperate with the treatment actively.

Factors affecting time to treatment initiation after diagnosis for multidrug-resistant/rifampicin-resistant tuberculosis patients: A mixed-methods study in Jakarta, Indonesia

OBJECTIVE

To investigate the time to treatment initiation (TTI) for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) patients after diagnosis in Indonesia and biological, psychological and social factors associated with the time interval.

METHODS

This study was conducted in Persahabatan Hospital, Jakarta using a mixed-methods approach. Registry data and medical records of MDR/RR-TB patients were collected and matched (hospital dataset), and linked with psychosocial assessment results (linked dataset). Descriptive analysis was conducted to understand patient characteristics and the distribution of TTI after RR-TB diagnosis by GeneXpert. Generalised linear regression was used to analyse factors associated with delay duration, and logistic regression to explore factors associated with the delay longer than the median duration for both datasets (basic vs. extended model). In-depth interviews were conducted with patients and healthcare workers to understand the procedure of treatment initiation and how different factors led to delay.

RESULTS

The hospital dataset included 275 patient-matched cases, and 188 were further linked with psychosocial assessment results. The median time interval was 24 days [interquartile range (IQR) 23.5] and 26 days (IQR 21.25), respectively. Regression analysis showed that in the extended model, comorbidities (exp [coefficient]= 1.93), unemployment (exp [coefficient] = 1.80) and poor knowledge of MDR/RR-TB (exp (coefficient) = 1.67) seemed to have the strongest effects on prolonging the time interval (p < 0.05). Unsuccessful TB treatment history was the only factor that significantly increased the risk of delay longer than the median duration (p < 0.05) in the basic model, while none of the factors were significant in the extended model. The qualitative study identified provider-side factors (centralised service provision and insufficient human resources) and patient-side factors (physical weakness, psychological stress and financial concern) associated with treatment delay.

CONCLUSION

MDR/RR-TB patients in Persahabatan Hospital, Jakarta, Indonesia waited around 25 days for treatment initiation after RR-TB diagnosis. Health system solutions are needed to address challenges facing both MDR/RR-TB patients and healthcare providers to reduce delay in treatment initiation.

Gridlock from diagnosis to treatment of multidrug resistant tuberculosis (MDR-TB) in Tanzania: patients' perspectives from a focus group discussion

BACKGROUND

Molecular diagnostics have revolutionized the diagnosis of multidrug resistant tuberculosis (MDR-TB). Yet in Tanzania we found delay in diagnosis with more than 70% of MDR-TB patients having a history of several previous treatment courses for TB signaling prior opportunities for diagnosis. We aimed to explore patients' viewpoints and experiences with personal and socio-behavioral obstacles from MDR-TB diagnosis to treatment in an attempt to understand these prior findings.

METHODS

The study was conducted in December 2016 with MDR-TB patients admitted at Kibong'oto Infectious Diseases Hospital. A qualitative approach deploying focus group discussions (FGDs) was used to gather information. Groups were sex aggregated to allow free interaction and to gauge gender specific issues in the social and behavioral contexts. The FGDs explored pathways and factors in the service delivery that may have contributed in the delay in accessing MDR-TB diagnostics and/or treatment. Collected data were coded, categorized and thematically interpreted.

RESULTS

Forty MDR-TB patients participated in six FGDs. Challenges and barriers contributing to the delay in accessing MDR-TB diagnosis to treatment were as follows: 1) Participants had a different understanding of MDR-TB that led to seeking services outside the conventional health system; 2) Socio-economic adversity made health-seeking behavior difficult and often unproductive; 3) In the health system, challenges included inadequacy of MDR-TB diagnostic centers, lack of knowledge on behalf of health care providers to consider MDR-TB and order appropriate diagnostics; 4) The specimen referral system for early diagnosis of MDR-TB was inefficient. Non-adherence of TB patients to first-line anti-TB drugs prior to MDR-TB diagnosis, given the multitude of barriers discussed, was coupled with both intentional and unintentional non-adherence of health care providers to international standards of TB care.

CONCLUSION

Patient-centered strategies bridging communities and the health system are urgently required for optimum MDR-TB control in Tanzania.

Treatment quality and outcome for multidrug-resistant tuberculosis patients in four regions of China: a cohort study

Background

China incurs an extremely low treatment coverage of multidrug-resistant tuberculosis (MDR-TB). This study aimed to understand the experience of MDR-TB patients on quality of health care, and the clinical impact through an up to six-year follow-up.

Methods

Cohorts of MDR-TB patients were built in TB/MDR-TB designated hospitals in four regions of China from 2014 to 2015. Patients were followed up during treatment course, and yearly confirmation afterward until 2019. Delay in MDR-TB diagnosis and treatment was calculated upon bacteriological confirmation and treatment initiation. Risk factors for unfavourable outcomes were identified by multivariate logistic regression.

Results

Among 1168 bacteriological-positive TB patients identified from a 12-million population, 58 (5.0%) MDR-TB cases were detected. The median delay for MDR-TB diagnosis was 90.0 days, with 13.8% having a delay above 180.0 days. MDR-TB treatment was only recommended to 19 (32.8%) participants, while the rest continued with regimen for drug-susceptible TB. In MDR-TB treatment group, 36.8% achieved treatment success, while the others had incomplete treatment (21.1%), loss to follow-up (36.8%) and TB relapse (5.3%). For non-MDR-TB treatment group, 33.3% succeeded, 25.6% relapsed, 2.6% failed, 23.1% died, and 15.4% were lost to follow-up. Overall, only 35.7% (20/56) of detected MDR-TB patients had favourable outcomes and higher education level was positively associated with it (adjusted odds ratio [aOR]: 3.60, 95% confidence interval [CI]: 1.04–12.5).

Conclusions

A large proportion of patients did not receive MDR-TB treatment and had unfavourable outcomes. Delayed MDR-TB diagnosis resulted in poor quality of MDR-TB care. Rapid diagnosis, regulated patient management and high-quality MDR-TB treatment should be enhanced in China.

Drug resistance and epidemiology characteristics of multidrug-resistant tuberculosis patients in 17 provinces of China

As China is one of high MDR-TB burden countries, it is important to determine the drug resistant pattern and clinical characteristics of multidrug resistant tuberculosis (MDR-TB). We conducted a comprehensive and nationwide study on MDR-TB in 17 provinces for the period from June 2009 to June 2015, and a total of 1154 cases of MDR-TB were finally investigated. The study sought to assess the clinical features and contrast drug susceptibility profiles of MDR-TB patients in China. Cavitary disease, young age, and long duration of TB disease among MDR-TB patients were important predictors. A high resistance proportion of first-line drugs was observed in Beijing, Shanghai and Tianjin. Resistant proportions of second-line anti-TB drugs in western region for amikacin, aminosalicylic acid, and levofloxacin were higher than eastern and central regions. High levels of drug resistance were seen in earlier cases (before 2011) and outpatients. We found high levels of resistance to 1st- and 2nd-line drugs in all settings, with considerable variabilities in terms of different Directly Observed Treatment Short Course (DOTS) programme, level of economic development(eastern, central and western regions) and patient source (inpatients and outpatients). Timely drug susceptibility testing (DST) and effective management are necessary to ensure an early detection of MDR-TB and its proper treatment.

A study on procedural delay in diagnosis and start of treatment in drug resistant tuberculosis under RNTCP

BACKGROUND

Multi-drug-resistant TB (MDR-TB) has become a significant public health problem and an obstacle to effective TB control. Rapid diagnostic tests for anti tubercular drugs sensitivity have significantly reduced total time in initiation of treatment. Still there is a significant gap between MDR diagnosis and start of category IV treatment. Delay in establishing the diagnosis may cause disease progression, transmission, lost to follow up and death. This study was planned to assess the actual delay from day one of sputum examination to the day of initiation of category IV in operational settings.

METHODOLOGY

MDR-TB suspected patients attending the Respiratory medicine department, JLNMC, Ajmer from June-15 to July-16 were followed from sputum examination to sample deposition for drug sensitivity testing (LPA/CBNAAT) to MDR detection to category IV initiation, for assessment of procedural delay at various steps.

RESULTS

LPA group (371 patients): Sputum smear to LPA deposition mean duration was 8.02 days, LPA deposition to LPA result upload mean duration was 3.78 days, LPA deposition to patients received LPA reports mean duration was 21.73 days and reports received to PMDT site admission (if drug resistant) mean duration was 3.61 days. Total time duration in category IV initiation was 32.63 days. CBNAAT group (50 patients): Sputum smear to CBNAAT deposition mean duration was 6.70 days, CBNAAT deposition to CBNAAT result upload mean duration was 1.13 days, CBNAAT deposition to patients received CBNAAT reports mean duration was 6.53 days and reports received to PMDT site admission (if R-resistant) mean duration was 3.8 days. Total time duration in category IV initiation was 12.4 days.

CONCLUSION

Major delay seen on part of receiving sensitivity reports indicates the need to stress upon field staff motivation, appropriate training, sensitisation and expert counselling.

Treatment delay and associated factors among adults with drug resistant tuberculosis at treatment initiating centers in the Amhara regional state, Ethiopia

Background

A delayed initiation of tuberculosis treatment results in high morbidity, mortality, and increased person-to-person transmissions. The aim of this study was to assess treatment delay and its associated factors among adult drug resistant tuberculosis patients in the Amhara Regional State, Ethiopia.

Methods

An institution based cross-sectional study was conducted on all adult drug resistant tuberculosis patients who initiated treatment from September 2010 to December 2017. Data were collected from patient charts, registration books, and computer databases using abstraction sheets. The data were entered using Epi-info version 7 and exported to SPSS version 20 for analysis. Summary statistics, like means, medians, and proportions were used to present it. Binary logistic regression was fitted; Adjusted Odds Ratio (AOR) with a 95% Confidence Interval (CI) was also computed. Variables with p-value < 0.05 in the multi-variable logistic regression model was declared as significantly associated with treatment delay.

Results

The median time to commence treatment after drug resistant tuberculosis diagnosis was 8 (IQR: 3–37) days. Being diagnosed by Line probe assay [AOR = 5.59; 95% CI: 3.48–8.98], Culture [AOR = 5.15; 95% CI: 2.53–10.47], and history of injectable anti-TB drugs [AOR = 2.12; 95% CI: 1.41–3.19] were associated with treatment delays.

Conclusion

Treatment delay was long, especially among patients diagnosed by Culture or LPA and those who had a prior history of injectable anti-TB drugs. That suggested that the need for universal accesses to rapid molecular diagnostic tests, such as Gene Xpert and the PMDT team were needed to promptly decide to minimize unnecessary delays.

Transmission of drug-resistant tuberculosis in HIV-endemic settings

The emergence and expansion of the multidrug-resistant tuberculosis epidemic is a threat to the global control of tuberculosis. Multidrug-resistant tuberculosis is the result of the selection of resistance-conferring mutations during inadequate antituberculosis treatment. However, HIV has a profound effect on the natural history of tuberculosis, manifesting in an increased rate of disease progression, leading to increased transmission and amplification of multidrug-resistant tuberculosis. Interventions specific to HIV-endemic areas are urgently needed to block tuberculosis transmission. These interventions should include a combination of rapid molecular diagnostics and improved chemotherapy to shorten the duration of infectiousness, implementation of infection control measures, and active screening of multidrug-resistant tuberculosis contacts, with prophylactic regimens for individuals without evidence of disease. Development and improvement of the efficacy of interventions will require a greater understanding of the factors affecting the transmission of multidrug-resistant tuberculosis in HIV-endemic settings, including population-based molecular epidemiology studies. In this Series article, we review what we know about the transmission of multidrug-resistant tuberculosis in settings with high burdens of HIV and define the research priorities required to develop more effective interventions, to diminish ongoing transmission and the amplification of drug resistance.

Delay in treatment initiation and treatment outcomes among adult patients with multidrug-resistant tuberculosis at Yangon Regional Tuberculosis Centre, Myanmar: A retrospective study

Background

Myanmar faces a health security threat, with an increasing number of multidrug-resistant tuberculosis (MDR-TB) cases. Long delays in the initiation of treatment are a barrier to MDR-TB control.

Objectives

The main objectives of this study were (1) to identify the determinants of delay in treatment initiation after MDR-TB diagnosis, and (2) to explore the effects of treatment delay on disease infectivity, severity, treatment adherence, and treatment outcomes.

Methods

This retrospective study reviewed 330 MDR-TB treatment cards for patients enrolled for treatment at Yangon Regional Tuberculosis Centre, in 2014.

Results

Median treatment delay was 105 days, interquartile range (IQR) 106 (61–167) days; (51.5%) of patients experienced a long treatment delay (≥ 105 days). Regarding the determinants of treatment delay, this study identified important patient-healthcare system interaction factors. Significant risk factors of long treatment delay included female sex, age > 30 years, and prior contact with patients with MDR-TB. Patients with long treatment delays were significantly different from those with short delays, in terms of having high sputum smear grade, resistance to more than two main drugs (isoniazid and rifampicin), and long culture conversion time. In this study, delay in the initiation of treatment was associated with poor treatment outcome, but this was not statistically significant after adjusting for other risk factors. Median treatment-delay times were longer among patients with poor outcomes (144 days) than those with successful outcomes (102 days).

Conclusions

Post-diagnosis delays in the initiation of treatment among MDR-TB patients were significantly long. The study results showed that inadequate MDR-TB treatment initiation center, centralization of treatment initiation, limitation of human resources, were health-system factors delaying timely treatment initiation and implementation of an effective TB-control program. Our findings highlight the need for immediate interventions to reduce treatment delay and improve treatment outcomes, including scaling up diagnostic capacity with Xpert MTB/RIF at township level, expansion of decentralized MDR-TB treatment initiation centers, ensuring a productive health workforce comprising trained health personnel, and providing health education and treatment-adherence counseling to patients and family members.

Delay in diagnosis and treatment among adult multidrug resistant tuberculosis patients in Yangon Regional Tuberculosis Center, Myanmar: a cross-sectional study

Background

Delays in diagnosis and treatment initiation may allow the emergence of new cases by transmission to the community, and is one of the challenges facing programme management of drug resistance in Myanmar. This study aimed to explore delays in diagnosis and treatment initiation, and associated factors among patients with multidrug-resistant tuberculosis.

Methods

A cross-sectional study was conducted at Yangon Regional Tuberculosis Centre, Myanmar. Data were collected by face-to-face interviews and treatment-card reviews of all adult patients who had registered and started treatment with the standard regimen from May to November, 2017. Delay time was categorized by using median cut-off and analyzed using SPSS version 23.0. Logistic regression analysis was performed to assess the relative impact of predictor variables on diagnosis and treatment delays.

Results

A total of 210 patients participated in this study. The median diagnosis delay was 9 days, IQR 3 (8–11) and 58.6% of the patients experienced a long diagnosis delay. Below middle school education (adjusted odds ratio [AOR] = 2.75, 95% CI = 1.22–6.21), non-permanent salaried employment (AOR = 3.03, 95% CI = 1.32–6.95), co-existing diabetes mellitus (AOR = 5.06, 95% CI = 1.97–13.01) and poor awareness (AOR = 2.99, 95% CI = 1.29–6.92) were independent predictors of long diagnosis delay. The median treatment delay was 13 days, IQR 9 (8–17) and 51% of the patients experienced long treatment delay. Age 31–50 years (AOR = 4.50, 95% CI = 1.47–13.97) and age > 50 years (AOR = 9.40, 95% CI = 2.55–34.83), history with MDR-TB patient (AOR = 3.16, 95% CI = 1.29–7.69), > 20 km away from a Regional TB Centre (AOR = 14.33, 95% CI = 1.91–107.64) and poor awareness (AOR = 4.62, 95% CI = 1.56–13.67) were independent predictors of long treatment delay.

Conclusions

Strengthening comprehensive health education, enhancing treatment adherence counseling, providing more Xpert MTB/RIF machines, expanding decentralized MDR-TB treatment centers, ensuring timely sputum transportation, provision of a patient support package immediately after confirmation, and strengthening contact-tracing for all household contacts with MDR-TB patients and active tuberculosis screening were the most effective ways to shorten delays in MDR-TB diagnosis and treatment initiation.

Diagnostic delay and mortality of active tuberculosis in patients after kidney transplantation in a tertiary care hospital in China

TB infection in patients after kidney transplantation remains a concern in a successful long-term outcome. This retrospective, descriptive study was performed on tuberculosis infection after kidney transplantation in the Department of Infectious Disease of the First Affiliated Hospital of Zhejiang University, a tertiary care hospital in China, from January 2011 to April 2017, with the aim to explain the clinical features of active tuberculosis after kidney transplantation and explore the correlated factors for diagnostic delay and mortality. It included 48 cases. All these cases were followed up for at least 12 months after anti-tuberculosis therapy, except the ones who died during this period. The median time of transplantation to active tuberculosis of these 48 patients was about 5.4 years. The time from a first hospital visit to the diagnosis (diagnostic delay) of 12 (25%) cases was more than 30 days. The correlated factors for the diagnostic delay more than 30 days were a fever for more than 2 weeks and antibiotic use for more than 2 weeks. Nine (18.8%) cases died during the anti-tuberculosis therapy or following-up period due to TB relapse. The risk factors for mortality were severe complications, such as encephaledema, severe pneumonia, intestinal perforation, liver function failure, and the following multiple-organ failure. In conclusion, the possibility of tuberculosis infection should be carefully assessed and sometimes diagnostic anti-tuberculosis therapy may be required for patients who had a fever for more than 2 weeks or used antibiotics for more than 2 weeks after kidney transplantation. Severe complications and the following multiple-organ failure might increase the mortality among these patients.

Estimating the global burden of multidrug-resistant tuberculosis among prevalent cases of tuberculosis

BACKGROUND

Estimates of the multidrug-resistant tuberculosis (MDR-TB) burden are based on incomplete, infrequently updated data among a limited pool of notified or incident pulmonary TB cases.

METHODS

Using World Health Organization data reported by 217 countries/territories in 2014, we calculated the MDR-TB burden among prevalent TB cases and compared these with estimates among incident and notified TB patients. We also compared treatment coverage across estimates.

RESULTS

Among prevalent TB patients worldwide in 2014, we estimate that 555 545 (95% credible bounds 499 340-617 391) MDR-TB cases occurred. This is 85% more than the 300 000 estimated among notified cases, and 16% more than the 480 000 among incident cases. Only 20% of MDR-TB cases among prevalent-compared to 37% of MDR-TB among notified-TB patients had access to MDR-TB treatment. Applying prior estimates, only 10% of MDR-TB cases will have successful outcomes.

CONCLUSION

Estimates based on likely-to-be-diagnosed cases of MDR-TB overlook a significant proportion of morbidity, mortality, and transmission that occur in undiagnosed, untreated, prevalent TB patients. Even though it may still likely underestimate the true disease burden, MDR-TB among patients with prevalent TB represents a closer approximation of disease burden than currently reported indicators. Progress toward elimination or control depends on policies guided by a more complete representation of the disease burden.

Gridlock from Diagnosis to Treatment of Multidrug-Resistant Tuberculosis (MDR-TB) in Tanzania: Illuminating Potential Factors for Possible Intervention

Settings

Kibong'oto Infectious Diseases Hospital, Kilimanjaro, Tanzania.

Objective

Characterise multidrug-resistant tuberculosis (MDR-TB)-treated cases during the scaling up of molecular diagnostics using Xpert MTB/RIF and GenoType MTBDRplus.

Design

Retrospective cohort study.

Results

A total of 223 MDR-TB patients were referred to the Kibong'oto Infectious Disease Hospital from January 2013 through December 2014. Four cities-Dar es Salaam, Mbeya, Mwanza, and Tanga-contributed 144 (65%) of referrals. Of the total referred patients, HIV coinfection was found in 92 (41%) and 180 (81%) had history of previous TB treatment. Molecular drug susceptibility testing (DST) contributed 201 (91%) of referrals and resulted in a shorter time from diagnosis to start of treatment, 30 days (95% confidence interval [CI], 26-37), compared to conventional phenotypic DST, 212 days (95% CI, 151-272; P<.001). Molecular DST found higher proportions of MDR-TB children and people living with HIV without prior treatment, 5 (12%) and 24 (56%), respectively, compared to those with previous treatment for TB, 4 (2%) and 68 (38%), respectively. The median CD4 count correspondingly was 131 cells/μl (IQR, 109-131) and 200 cells/μl (IQR, 94-337) for MDR-TB diagnosed by phenotypic and molecular diagnostics (P=.70). Despite the more rapid time to treatment initiation among patients diagnosed by molecular DST, treatment outcomes, including time to sputum culture conversion, did not differ compared to those diagnosed with conventional phenotypic DST. Regardless of the method of diagnosis, MDR-TB/HIV coinfected patients who died had lower CD4 counts (mean 86 ± 87 cells/μl) than survivors (mean 274 ± 224 cells/μl; P=.02).

Conclusion

Molecular diagnostics appear to speedup the time to treatment initiation, but may not improve other treatment outcomes.

Resistance to Second-Line Antituberculosis Drugs and Delay in Drug Susceptibility Testing among Multidrug-Resistant Tuberculosis Patients in Shanghai

Introduction. Second-line antituberculosis drugs (SLDs) are used for treating multidrug-resistant tuberculosis (MDR-TB). Prolonged delays before confirming MDR-TB with drug susceptibility testing (DST) could result in transmission of drug-resistant strains and inappropriate use of SLDs, thereby increasing the risk of resistance to SLDs. This study investigated the diagnostic delay in DST and prevalence of baseline SLD resistance in Shanghai and described the distribution of SLD resistance with varied delays to DST. Methods. All registered patients from 2011 to 2013 in Shanghai were enrolled. Susceptibility to ofloxacin, amikacin, kanamycin, and capreomycin was tested. Total delay in DST completion was measured from the onset of symptoms to reporting DST results. Results. Resistance to SLDs was tested in 217 of the 276 MDR-TB strains, with 118 (54.4%) being resistant to at least one of the four SLDs. The median total delay in DST was 136 days. Patients with delay longer than median days were roughly twice more likely to have resistance to at least one SLD (OR 2.22, 95% CI 1.19-4.11). Conclusions. During prolonged delay in DST, primary and acquired resistance to SLDs might occur more frequently. Rapid diagnosis of MDR-TB, improved nosocomial infection controls, and regulated treatment are imperative to prevent SLD resistance.

The effect of early versus late treatment initiation after diagnosis on the outcomes of patients treated for multidrug-resistant tuberculosis: a systematic review

BACKGROUND

Globally it is estimated that 480 000 people developed multidrug-resistant tuberculosis (MDR-TB) in 2014 and 190 000 people died from the disease. Successful treatment outcomes are achieved in only 50 % of patients with MDR-TB, compared to 86 % for drug susceptible disease. It is widely held that delay in time to initiation of treatment for MDR-TB is an important predictor of treatment outcome. The objective of this review was to assess the existing evidence on the outcomes of multidrug- and extensively drug-resistant tuberculosis patients treated early (≤4 weeks) versus late (>4 weeks) after diagnosis of drug resistance.

METHODS

Eight sources providing access to 17 globally representative electronic health care databases, indexes, sources of evidence-based reviews and grey literature were searched using terms incorporating time to treatment and MDR-TB. Two-stage sifting in duplicate was employed to assess studies against pre-specified inclusion and exclusion criteria. Only those articles reporting WHO-defined treatment outcomes were considered for inclusion. Articles reporting on fewer than 10 patients, published before 1990, or without a comparison of outcomes in patient groups experiencing different delays to treatment initiation were excluded.

RESULTS

The initial search yielded 1978 references, of which 1475 unique references remained after removal of duplicates and 28 articles published pre-1990. After title and abstract sifting, 64 papers underwent full text review. None of these articles fulfilled the criteria for inclusion in the review.

CONCLUSIONS

Whilst there is an inherent logic in the theory that treatment delay will lead to poorer treatment outcomes, no published evidence was identified in this systematic review to support this hypothesis. Reports of programmatic changes leading to reductions in treatment delay exist in the literature, but attribution of differences in outcomes specifically to treatment delay is confounded by other contemporaneous changes. Further primary research on this question is not considered a high priority use of limited resources, though where data are available, improved reporting of outcomes by time to treatment should be encouraged.