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In 2014, there were 480 000 new cases of multidrug-resistant tuberculosis (MDR-TB) around the world, but only 25% of them were diagnosed and reported. Drug resistance in TB is necessarily a laboratory diagnosis. An urgent priority in everyday practice is to diagnose tuberculosis and rule out drug resistance as quickly and as accurately as possible. However, worldwide, only 12% of new bacteriologically confirmed TB cases and 58% of previously treated TB cases were tested for drug resistance in 2014. New tools for diagnosis of TB and drug-resistant TB have been introduced for clinical practice during the past decade. Those new tools can detect and identify drug resistance to antituberculosis drugs in less than 24 hours, and they should be urgently integrated into clinical practice, especially in high-burden regions. Ongoing transmission of TB generates new infections, and this infected population is the inexhaustible source of new TB cases. If we are really determined to stop the global TB epidemic, we need to treat active cases and also halt the transmission of the infection. The only strategy for preventing the development of active disease in individuals with subclinical infection is to give treatment for this latent infection. Global control of TB requires a huge investment of funds to address current detection and treatment gaps. We must reconsider our current strategy and combine social components with biomedical interventions. This will require the development of alliances between government and civil society, as well as leadership and true political commitment at the highest level of government. [ABSTRACT FROM AUTHOR]

Objective. To assess whether the National Tuberculosis Program (NTP) guidelines for culture and drug sensitivity testing (DST) in Guatemala were successfully implemented, particularly in cases of smear-negative pulmonary tuberculosis (TB) or previously treated TB, by documenting notification rates by department (geographic area), disease type and category, and culture and DST results. Methods. This was a cross-sectional, operational research study that merged and linked all patients registered by the NTP and the National Reference Laboratory in 2013, eliminating duplicates. The proportions with culture (for new smear negative pulmonary cases) and culture combined with DST (for previously treated patients) were estimated and analyzed by department. Data were analyzed using EpiData Analysis version 2.2. Results. There were 3 074 patients registered with TB (all forms), for a case notification rate of 20/100 000 population. Of these, 2 842 had new TB, of which 2 167 (76%) were smear-positive pulmonary TB (PTB), 385 (14%) were smear-negative PTB, and 290 (10%) were extrapulmonary TB. There were 232 (8%) previously treated cases. Case notification rates (all forms) varied by department from 2-68 per 100 000 population, with the highest rates seen in the southwest and northeast part of Guatemala. Of new TB patients, 136 had a culture performed and 55 had DST of which the results were 33 fully sensitive, 9 monoresistant, 3 poly resistant, and 10 multidrug resistant TB (MDR-TB). Only 21 (5%) of new smear-negative PTB patients had cultures. Of 232 previously treated patients, 54 (23%) had a culture and 47 (20%) had DST, of which 29 were fully sensitive, 7 monoresistant, 2 polyresistant, and 9 MDR-TB. Of 22 departments (including the capital), culture and DST was performed in new smear-negative PTB in 7 departments (32%) and in previously treated TB in 13 departments (59%). Conclusions. Despite national guidelines, only 5% of smear-negative PTB cases had a culture and only 20% of previously treated TB had a culture and DST. Several departments did not perform culture or DST. These short comings must be improved if Guatemala is to curtail the spread of drug resistant forms of TB, while striving to eliminate all TB. [ABSTRACT FROM AUTHOR]

This study documented the number and results of mycobacterial culture and drug sensitivity testing (CDST) in Mexico from 2009-2013 and assessed whether states with a higher risk of multidrug-resistant tuberculosis (MDR-TB) performed more CDST and had more cultures showing MDR-TB. Data for this longitudinal, descriptive, operational research study came from the electronic records of 31 state public health laboratories in Mexico. The total number of CDSTs was 6 470, increasing from 2 143 in the first 2 years to 4 327 in the latter 3 years. There was a significant increase in the proportion of cultures showing sensitivity to all drugs, from 53.1% to 60.9% in 2011-2013 (P < 0.001) and a significant decrease in the proportion showing MDR-TB, from 28.2% in 2009 to 19.8% in 2013 (P < 0.001). Cases of extensively drug resistant tuberculosis were < 1 % per year. In the 12 states with higher risk for MDR-TB, significantly more CDSTs (2 382 test) were done in 2011-2013 than in the other 19 states (1 945 tests). Also, for each year the proportion of cultures showing MDR-TB was significantly higher in high risk MDR-TB states than in lower risk ones (P < 0.001). During the 5-year study period, CDST was scaled up in Mexico, particularly in high-risk MDR-TB states where a higher proportion of cultures showed MDR-TB. Scale up and wider coverage of CDST should continue. [ABSTRACT FROM AUTHOR]

Multidrug-resistant tuberculosis (MDR-TB) is a major public health concern that threatens global progress toward effective TB control. The risk of MDR-TB is increased in patients who have received previous TB treatment. This article describes the performance of culture and drug susceptibility testing (DST) in patients registered as previously treated TB patients in the Dominican Republic in 2014, based on operational research that followed a retrospective cohort design and used routine program data. Under the current system of TB culturing and DST, the majority of patients with previously treated TB do not undergo DST, and those who do often experience considerable delay in obtaining their results. The lack of DST and delay in receiving DST results leads to underestimation of the number of MDR-TB cases and hinders the timely initiation of MDR-TB treatment. . [ABSTRACT FROM AUTHOR]

Objective. To determine the use and performance of a line probe assay (LPA) compared with conventional culture and drug sensitivity testing (CDST) in patients registered with tuberculosis (TB) under routine program conditions in Peru in 2011-2013. Methods. This was a descriptive, operational research, cross-sectional study of sputum specimens from patients with smear-positive pulmonary TB and mycobacterial cultures from patients with smear-negative or positive TB. Drug resistance to rifampicin and/or isoniazid detected by LPA was compared to CDST. Sensitivity, specificity, and predictive values were calculated and reliability for detecting drug resistance was assessed through kappa coefficient, with values 0.61-0.80 showing substantial correlation, and 0.81 or above showing almost-perfect correlation. Results. In 2011-2013, there were 16169 LPA tests performed, with the proportion of TB patients receiving the test increasing from 3.2% to 30.2%. In all, 2 905 LPA test results were compared to CDST. For LPA in sputum specimens, sensitivity for rifampicin was 92%; isoniazid, 94%; and MDR-TB, 88%; while specificity for rifampicin was 92%; isoniazid, 92%; and MDR-TB, 95%. For LPA in mycobacterial cultures, sensitivity for rifampicin was 95%; isoniazid, 96%; and MDR-TB, 90%; while specificity for rifampicin was 85%; isoniazid, 91%; and MDR-TB, 94%. Kappa coefficients were at 0.81 or above for all comparisons of LPA with CDST using sputum specimens and cultures, except for isoniazid in cultures, which was at 0.79. Conclusions. This study suggests that LPA is a reliable and rapid screening test for drug-resistant TB and should be considered suitable for routine use and scale up in Peru. [ABSTRACT FROM AUTHOR]

Objective. To examine direct and indirect costs incurred by new, retreatment, and multidrug-resistant (MDR) tuberculosis (TB) patients in the Dominican Republic before and during diagnosis, and during treatment, to generate an evidence base and formulate recommendations. Methods. The "Tool to Estimate Patients' Costs" was adapted to the local setting, translated into Spanish, and pretested. Patients attending 32 randomly selected health facilities in six chosen study areas on the study days were interviewed. Responses from patients 18-65 years old who had received treatment for at least one month and provided signed informed consent were collected, entered into a database, and analyzed. Results. A total of 200 patients were interviewed. For most respondents, direct and indirect costs increased while income decreased. Total costs amounted to a median of US$ 908 for new patients, US$ 432 for retreatment patients, and US$ 3 557 for MDR-TB patients. The proportion of patients without a regular income increased from 1% to 54% because of falling ill with TB. Following its review of the study results the Ministry of Health has made efforts to allocate public funds for food supplements and to include in- and outpatient TB services in the national health insurance schemes. Conclusions. Free TB diagnosis and treatment are not enough to alleviate the financial constraints experienced by vulnerable groups as a result of the illness. Health insurance covering TB in- and outpatient costs is critical to prevent TB-related financial hardship. [ABSTRACT FROM AUTHOR]

Objective. To determine the prevalence of multidrug-resistant tuberculosis (MDR-TB) among patients with new smear-positive pulmonary TB in Port-au-Prince, Haiti. Methods. Sputum samples were cultured from 1 006 patients newly diagnosed with TB in 2008. The core region of the rpoB gene that is associated with resistance to rifampin was sequenced. All isolates with rpoB mutations were sent to the New York State reference laboratory for conventional drug susceptibility testing (DST). All isolates were also tested with the GenoType MTBDRplus line-probe assay. Results. Mycobacterium tuberculosis was isolated from 906 patients. Twenty-six (2.9%) of the isolates had missense mutations or deletions in rpoB and were resistant to rifampin by DST. All 26 were also resistant to isoniazid and classified as MDR-TB. Forty-six control isolates without rpoB mutations were found to be rifampin sensitive by DST. The GenoType MTBDRplus line-probe assay correctly identified 26 MDR-TB strains. It misclassified one pansusceptible isolate as rifampin resistant. Conclusions. This study shows an MDR-TB prevalence of 2.9% in newly diagnosed TB patients in Haiti and suggests that rpoB sequencing and hybridization assays are good screening tools for early detection of MDR-TB. [ABSTRACT FROM AUTHOR]

Objectives. In a pilot implementation project of the microscopic-observation drug-susceptibility methodology, we conducted a process evaluation to identify health system and logistic challenges that need to be addressed in order to harness the benefits of rolling out promising new diagnostic tools for multidrug-resistant tuberculosis (MDRTB). Methods. Regional data relating to health system practices and performance related to the MDRTB diagnostic algorithm were collected at health center, local, and regional laboratories. Results. Parallel implementation of a new test and an existing method creates demands on funds, personnel, sample transport, and information systems in addition to new test startup costs. Obviating the need for primary culture at intermediate laboratories through direct drug susceptibility testing (DST) at the regional reference laboratory significantly reduces delay. Field application of well-defined national guidelines for DST is patchy. If fidelity to national guidelines were perfect, DST requests would increase more than 50-fold, with important implications for laboratory capacity. Conclusions. Implementing a new MDRTB diagnostic presents challenges to the laboratory environment, the existing DST process, and the application of national guidelines in peripheral clinics. Assessing each element can maximize efficient use of a new tool. Specifically, strengthening systems for transferring samples to the laboratory and delivering results to the requesting clinic in addition to investing in personnel and laboratory resources are integral to harnessing the benefits of high-performance new diagnostic tests and can bring added value to other programs in the health care system. [ABSTRACT FROM AUTHOR]