BackgroundMulti drug resistant tuberculosis (MDR-TB) poses formidable challenges to TB control due to its complex diagnostic and treatment challenges and often associated with a high rate of mortality. Accurate and rapid detection of MDR-TB is critical for timely initiation of treatment. Line Probe Assay (LPA) is a qualitative in vitro diagnostic test based on DNA-STRIP technology for the identification of the M. tuberculosis complex and its resistance to rifampicin (RMP) and/or isoniazid (INH). Hain Lifescience, GmbH, Germany has improved the sensitivity of Genotype MTBDRplus VER 2.0 LPA for the detection of MDR-TB; with the possibility of applying the tool in smear negative sputum samples.MethodA cross sectional study was conducted on 274 presumptive MDR-TB patients referred to the National TB Reference Laboratory (NTRL), Ethiopian Public Health Institute (EPHI) who submitted sputum samples for laboratory diagnosis of drug resistant-TB testing. Seventy-two smear and culture positive samples processed in smear positive direct LPA category and 197 smear negative sputum samples were processed for direct LPA. Among the smear negative samples 145 (73.6%) were culture negative and 26 (13.2%) were culture positive. All specimens were processed using NALC-NaOH method and ZN smear microscopy done from sediments. Genotype MTBDRplus VER 2.0 done from processed sputum sediments and the result was compared against the reference, BACTEC MGIT 960 culture and DST. Sensitivity, specificity, PPV and NPV of Genotype MTBDRplus VER 2.0 assay was determined and P-value <0.05 was considered as statistically significant.ResultsThe sensitivity, specificity, PPV and NPV of Genotype MTBDRplus VER 2.0 LPA were 96.4, 100, 100 and 96.9%, respectively for the detection of MDR-TB from direct smear positive sputum samples. The sensitivity, specificity, PPV and NPV of Genotype MTBDR plus VER 2.0 LPA were 77.8, 97.2, 82.4 and 97.2%, respectively, for the detection of M. tuberculosis from direct smear negative sputum samples. Fourteen (53.8%) samples had valid results with LPA among the 26 smear negative culture positive samples. The remaining 8 (30.8%) and 4 (15.4%) were invalid and negative with LPA, respectively. The sensitivity and specificity of Genotype MTBDRplus VER 2.0 LPA were 100% for the detection of MDR-TB among 14 direct smear negative and culture positive sputum samples.The most common mutations associated with RMP and INH resistance were S531L and S315TL, respectively. A single rare mutation (C15T/A16G) was detected for INH resistance.ConclusionThe diagnostic performance of Genotype MTBDRplus VER 2.0 LPA in direct smear positive sputum sample was highly sensitive and specific for early detection of MDR-TB. However, the diagnostic performance of this molecular assay in direct smear negative sputum sample was low and showed a high level of invalid results for detection of M. tuberculosis and its resistance to RMP and/or INH so it is unlikely to implement Genotype MTBDRplus VER 2.0 for the detection of MDR-TB in direct smear negative ...

Background: Consumers' health would be at risk unless food preparation and handling hygiene is ensured by food establishments. Literature indicates that poor food handling and sanitation practices are more common among food handlers in developing countries resulting in food-borne illness. Hence, food handlers can play a significant role in ensuring food hygiene. To this end, the paper aims to assess the level of food hygiene practices and its associated factors of food handlers working in food establishments in Bole sub-city, Addis Ababa, Ethiopia. Methods: Through across-sectional study design, a total of 394 food handlers selected randomly from food establishments have participated in the study. The data were collected between July and December 2017, through interview and observation. Percentage, cross tabulations, and logistic regressions were used to analyze the data. Results: The findings show that among 394 study subjects only 27.4% (i.e., 108 food handlers), were found to have good food hygiene practices. In other words, majority of food handlers observed were poor in maintaining food hygiene. Food hygiene practices were highly influenced by level score of favorable attitude (AOR = 3.9, 95% CI = 1.93, 7.87), extensive knowledge towards food hygiene (AOR= 3.33, 95% CI= 1.93, 5.76) and availability of water storage equipment at food establishments (AOR= 2.67, 95% CI= 1.38, 5.15). Conclusion: Food handlers had poor food hygiene practices in the study area. Shortages of a continuous water supply at food establishments, poor knowledge, and unfavorable attitude of food handlers towards food hygiene practice were all contributing factors associated with poor food hygiene practice. However, these can be improved through health education programs and environmental health services, such as periodic inspections, effective enforcement of food safety regulations, and enhancing the capacity of food hygiene regulators.

One of the key immunological characteristics of active visceral leishmaniasis (VL) is a profound immunosuppression and impaired production of Interferon-γ (IFN-γ). However, recent studies from Bihar in India showed using a whole blood assay, that whole blood cells have maintained the capacity to produce IFN-γ. Here we tested the hypothesis that a population of low-density granulocytes (LDG) might contribute to T cell responses hyporesponsiveness via the release of arginase. Our results show that this population is affected by the anticoagulant used to collect blood: the frequency of LDGs is significantly lower when the blood is collected with heparin as compared to EDTA; however, the anticoagulant does not impact on the levels of arginase released. Next, we assessed the capacity of whole blood cells from patients with active VL to produce IFN-γ and IL-10 in response to antigen-specific and polyclonal activation. Our results show that whole blood cells produce low or levels below detection limit of IFN-γ and IL-10, however, after successful treatment of VL patients, these cells gradually regain their capacity to produce IFN-γ, but not IL-10, in response to activation. These results suggest that in contrast to VL patients from Bihar, India, whole blood cells from VL patients from Gondar, Ethiopia, have lost their ability to produce IFN-γ during active VL and that active disease is not associated with sustained levels of IL-10 production following stimulation.

Background The diagnoses of active smear negative PTB, remains difficult. As a result, treatment is often carried out empirically relaying on clinical criteria. The distribution and magnitude of smear negative PTB, smear negative MDR-TB and associated factors in the same day diagnosis strategy are not clearly known in the study area. Therefore, this study aimed to determine the prevalence of TB, MDR-TB and associated risk factors among presumptive smear negative pulmonary tuberculosis patients in Addis Ababa, Ethiopia. Methods Analytic cross sectional study design was used. A total of 418 smear negative presumptive pulmonary TB patients were enrolled from selected health facilities since August 01, 2017 to January 5, 2018. Sputum samples were examined by Ziehl Neelsen microscopy, Xpert MTB/RIF assay and Culture. Drug susceptibility testing was performed by line probe assay and BACTEC MGIT 960 system. These laboratory tests were performed in Ethiopian Public Health Institute, National TB Reference Laboratory. Data was analyzed by SPSS Ver.20. Results From the total of 418 enrolled patients, 27 (6.5%) were Xpert MTB/ RIF and 26 (6.4%) were culture confirmed smear negative PTB patients. The positivity rate among male and female was 10.2 and 3.5% ( p = 0.005) respectively. From 26 culture positive isolates 3 (11.54%) were MDR TB; from MDR-TB confirmed isolates 2/23 (8.7%) were among new and 1/3 (33.3%) was among retreatment smear negative presumptive pulmonary TB patients. All Rifampicin resistant smear negative pulmonary TB isolates by Xpert MTB/ RIF assay were found to be MDR TB and 7/26 (26.9%) isolates were INH mono resistant. History of migration found to be a potential factor for developing smear negative pulmonary TB. Conclusion In this study a significant proportion of smear negative pulmonary TB was diagnosed. Furthermore, a high smear negative multi drug resistant (MDR) TB and other mono drug resistant TB prevalence was confirmed. Due to the limitations of smear microscopy which is used as a primary diagnostic tool, these TB strains are missed to be diagnosed and transmission continues in the community.

Immunologically, active visceral leishmaniasis (VL) is characterized by profound immunosuppression, severe systemic inflammatory responses, and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication, and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis; however, their role in human VL is poorly understood. In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-leishmanial treatment. Our results show that neutrophils are highly activated and have degranulated; high levels of arginase, myeloperoxidase, and elastase, all contained in neutrophils’ granules, were found in the plasma of VL patients. In addition, we show that a large proportion of these cells are immature. We also analyzed effector functions of neutrophils that are essential for pathogen clearance and show that neutrophils have an impaired capacity to release neutrophil extracellular traps, produce reactive oxygen species, and phagocytose bacterial particles, but not Leishmania parasites. Our results suggest that impaired effector functions, increased activation, and immaturity of neutrophils play a key role in the pathogenesis of VL.