Prevalence and Drug Resistance Pattern of Mycobacterium tuberculosis Isolated from Tuberculosis Patients in Basra, Iraq

Drug-resistant Mycobacterium tuberculosis (DR-MTB) is a major health threat to human beings. This study aimed to evaluate the prevalence and drug resistance profile of MTB. Data were collected from 2,296 newly diagnosed, and 246 retreated tuberculosis (TB) patients who attended the Advisory Clinic for Chest Diseases and Respiratory in Basra province from January 2016 to December 2020. Both new diagnostic and retreated TB cases showed that DR-MTB cases were significantly higher at age 15–34 years, pulmonary TB, and urban residents but with no significant difference regarding gender. The drugs resistance was significantly higher among the retreated cases compared with the new diagnostic patients (20.3% vs. 2.4%, p < 0.0001), with the percentage of the resistance to first-line drugs in primary and secondary cases including isoniazid (1% and 17.1%), rifampicin (0.78% and 15.8%), ethambutol (0.56% and 8.5%), streptomycin (1.3% and 9.75%). Notice that the most common drug resistance was against streptomycin with 1.3% in new patients and against isoniazid (17.1%) in retreated patients. The rate of total drug-resistant TB, multi-drug resistant TB, mono-drug resistant TB, and rifampicin-resistant TB among new tuberculosis cases increased in this period from 2.2 to 6.7%, 0.17 to 1.6%, 0.85 to 4%, and 0.17 to 4%, with a percentage change of 204.54, 841.17, 370.58, 22.5%, respectively. The rates of poly drug-resistant TB and ethambutol-resistant-TB dropped in this period by 15.96%, and 0.7%, with a decrease from 1.19 to 1% and from 1 to 0.3%, respectively. Similarly, the increase of drug-resistant TB among secondary cases has also occurred. In conclusion, the temporal trend showed an increase in the rate of drug resistance of M. tuberculosis since 2016, with a predominant multi-drug-resistant TB and isoniazid-resistant TB.

Tropical fever in remote tropics: tuberculosis or melioidosis, it depends on the lab

Diagnostics tests used to identify the cause of infection using proteomics and genomics have revolutionised microbiology laboratories in recent times. However, approaches to build the capacity of clinical microbiology services in the rural tropics by simply transplanting these approaches have proven difficult to sustain. Tropical fever in the remote tropics is, by definition, a clinical diagnosis where the aetiology of fever is not known, treatment is empirical, guided by clinical suspicion with treatment failure often attributed to incorrect diagnosis or antimicrobial resistance. Tuberculosis (TB) in rural Papua New Guinea (PNG) is mostly diagnosed clinically, perhaps supported by microscopy. In fact, a ‘tuberculosis patient’ in rural PNG is included in the TB register upon commencement of TB treatment with or without any laboratory-based evidence of infection. The roll-out of GeneXpert is continuing to transform TB diagnostic certainty in TB endemic communities. Melioidosis is endemic in tropical regions and is increasingly reported to mimic TB. Isolation and identification of the causative agent Burkholderia pseudomallei remains the gold standard. Here, we discuss the increasing divide between rural and urban approaches to laboratory-based infection diagnosis using these two enigmatic tropical infectious diseases, in rural PNG, as examples.

Retrospective analysis of multidrug-resistant tuberculosis case notifications in Australia (1999-2018)

This study describes the epidemiology and treatment outcomes of multidrug-resistant tuberculosis (MDR-TB) cases notified in Australia between 1999 and 2018, and investigates whether current data fields in the national tuberculosis (TB) dataset allow description and measurement of surveillance information pertaining to the diagnosis and clinical management of MDR-TB. In May 2019, de-identified demographic, clinical, laboratory, drug susceptibility, treatment, risk factor and outcome data for all MDR-TB case notifications were extracted from the Australian National Notifiable Disease Surveillance System. The dataset included ten treatment outcome categories, which were aggregated to four categorical outcomes for descriptive and inferential analyses. The majority of cases were overseas-born (91%). Absolute case numbers increased over time; however, the MDR-TB notification rate remained fairly stable during the study period. Treatment success was achieved in nearly two-thirds of cases (62.1%). Whilst timeframes between initial presentation, specimen collection, case notification and treatment commencement were calculated, current data fields in the national dataset precluded measurement and description of other parameters deemed important for MDR-TB surveillance. This study demonstrates that while Australia's MDR-TB burden is low, cases will continue to occur until TB control improves in countries with which Australia shares cultural and migration links. Australia should continue to support national and regional TB control programmes to sustain progress towards national elimination of TB. This study's findings support a review of data fields in the national TB dataset with potential expansion or adjustment to improve national data reporting, including the monitoring of evidence-based recommendations for the prevention and management of MDR-TB.

Spatial distribution of tuberculosis in a rural region of Western Province, Papua New Guinea

Introduction

There is a high burden of tuberculosis (TB) in the Western Province, Papua New Guinea. This study aims to describe the spatial distribution of TB in the Balimo District Hospital (BDH) catchment area to identify TB patient clusters and factors associated with high rates of TB.

Methods

Information about TB patients was obtained from the BDH TB patient register for the period 26 April 2013 to 25 February 2017. The locations of TB patients were mapped, and the spatial scan statistic was used to identify high- and low-rate TB clusters in the BDH catchment area.

Results

A total of 1568 patients were mapped with most being from the Balimo Urban (n = 252), Gogodala Rural (n = 1010) and Bamu Rural (n = 295) local level government (LLG) areas. In the Gogodala region (Balimo Urban and Gogodala Rural LLGs), high-rate clusters occurred closer to the town of Balimo, while low-rate clusters were located in more remote regions. In addition, closer proximity to Balimo was a predictor of high-rate clustering.

Discussion

There is heterogeneity in the distribution of TB in the Balimo region. Active case-finding activities indicated potential underdiagnosis of TB and the possibility of associated missed diagnoses of TB. The large BDH catchment area emphasizes the importance of the hospital in managing TB in this rural region.

Diversity of Mycobacterium tuberculosis in the Middle Fly District of Western Province, Papua New Guinea: microbead-based spoligotyping using DNA from Ziehl-Neelsen-stained microscopy preparations

Tuberculosis remains the world's leading cause of death from an infectious agent, and is a serious health problem in Papua New Guinea (PNG) with an estimated 36,000 new cases each year. This study describes the genetic diversity of Mycobacterium tuberculosis among tuberculosis patients in the Balimo/Bamu region in the Middle Fly District of Western Province in PNG, and investigates rifampicin resistance-associated mutations. Archived Ziehl-Neelsen-stained sputum smears were used to conduct microbead-based spoligotyping and assess genotypic resistance. Among the 162 samples included, 80 (49.4%) generated spoligotyping patterns (n = 23), belonging predominantly to the L2 Lineage (44%) and the L4 Lineage (30%). This is consistent with what has been found in other PNG regions geographically distant from Middle Fly District of Western Province, but is different from neighbouring South-East Asian countries. Rifampicin resistance was identified in 7.8% of the successfully sequenced samples, with all resistant samples belonging to the L2/Beijing Lineage. A high prevalence of mixed L2/L4 profiles was suggestive of polyclonal infection in the region, although this would need to be confirmed. The method described here could be a game-changer in resource-limited countries where large numbers of archived smear slides could be used for retrospective (and prospective) studies of M. tuberculosis genetic epidemiology.

A retrospective study of tuberculosis outcomes in Gulf Province, Papua New Guinea

Setting

Gulf Province, a rural area of mainland Papua New Guinea, is known to have one of the highest burdens of tuberculosis (TB) in the country.

Objectives

To describe the characteristics and outcomes of TB patients registered for first-line treatment in Kerema General Hospital in Gulf Province between January and December 2016.

Design

This was a retrospective cohort study using routinely collected programme data.

Results

Of 347 cases with a recorded TB site, 54% were male and 32% were aged <15 years. No human immunodeficiency virus (HIV) status was recorded for 51% of cases. TB was bacteriologically confirmed in 23% of cases. Among the cohort, there were 145 extrapulmonary TB cases (42%); the site of disease was unknown in 56% of these cases. Of the 297 cases with treatment outcome evaluated, 56% had a favourable outcome and 26% were lost to follow-up. On multivariable analysis, extrapulmonary TB (adjusted OR [aOR] 0.51, 95%CI 0.30-0.88, P = 0.02) and bacteriologically confirmed TB (aOR 0.40, 95%CI 0.21-0.77, P < 0.01) were associated with decreased odds of an unfavourable treatment outcome.

Conclusion

The study findings highlight the need to improve TB diagnosis, access to HIV testing, treatment adherence, patient support and the quality of TB programme data in Gulf Province.

Molecular Evidence of Drug-Resistant Tuberculosis in the Balimo Region of Papua New Guinea

Papua New Guinea (PNG) has a high burden of tuberculosis (TB), including drug-resistant TB (DR-TB). DR-TB has been identified in patients in Western Province, although there has been limited study outside the provincial capital of Daru. This study focuses on the Balimo region of Western Province, aiming to identify the proportion of DR-TB, and characterise Mycobacterium tuberculosis (MTB) drug resistance-associated gene mutations. Sputum samples were investigated for MTB infection using published molecular methods. DNA from MTB-positive samples was amplified and sequenced, targeting the rpoB and katG genes to identify mutations associated with rifampicin and isoniazid resistance respectively. A total of 240 sputum samples were collected at Balimo District Hospital (BDH). Of these, 86 were classified as positive based on the results of the molecular assays. For samples where rpoB sequencing was successful, 10.0% (5/50, 95% CI 4.4–21.4%) were considered rifampicin-resistant through detection of drug resistance-associated mutations. We have identified high rates of presumptive DR-TB in the Balimo region of Western Province, PNG. These results emphasise the importance of further surveillance, and strengthening of diagnostic and treatment services at BDH and throughout Western Province, to facilitate detection and treatment of DR-TB, and limit transmission in this setting.