ObjectivesTo assess the performance of Xpert MTB/RIF, an automated molecular test for Mycobacterium tuberculosis (MTB) and resistance to rifampin (RIF), against smear microscopy and culture method for diagnosis of MTB infection.MethodsThis is a retrospective analysis of 103 respiratory and 137 non-respiratory patient specimens suspected of tuberculosis at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia performed between April 2014 and March 2015. Each sample underwent smear microscopy, mycobacterial culture, and GeneXpert MTB/RIF test.ResultsFifteen out of 103 respiratory samples were smear and culture positive, whereas 9 out of 137 non-respiratory samples were smear positive. Out of 9 smear positive specimens, 8 were also culture positive. All 15 culture positive respiratory samples were detected by Xpert MTB/RIF (sensitivity and positive predictive value [PPV]=100%). Similarly, all 8 culture positive non-respiratory specimens were identified by Xpert MTB/RIF (sensitivity 100%; PPV 88.8%). The Xpert MTB/RIF detected only one false positive result in 88 smear negative respiratory specimens (specificity 98.9%; negative predictive value [NPV]= 100%). All 125 smear negative non-respiratory specimens tested negative by culture and Xpert MTB/RIF (sensitivity, specificity, PPV, NPV= 100%).ConclusionThe performance of Xpert MTB/RIF was comparable to the gold standard culture method for identification of MTB in both respiratory and non-respiratory clinical specimens.

No abstract

Pakistan is a farming and agricultural country facing energy issues from many years due to an increase in population and lack of technological development. Biomass is usually considered a waste. It is a major renewable energy source that is abundantly present in Pakistan. The wood residue is one of the potential biomasses to be used for energy purposes. Wood residue densification is considered a source of energy in this article. The effect of different pretreatments and binders (natural and synthetic) concentrations (5%, 10%, and 15%) on the densification of wood residue are analyzed. In addition to this, densified biomass pellets are characterized by physical, mechanical, thermal, and structural properties. The results indicated that densified pellets with 5% natural binder (rice binder) are found to be better in physical, mechanical, and thermal properties (IRI = 316, HV = 5396.3 Cal/g). The durability of the pellets with binder concentration is found to be linked with the bonding characteristics. It shows insights into the use of different biomass materials for energy generation to fulfill the demands of increasing commercialization and population. It indicates future prospects for better access to energy, reliable quality of air, and security of energy simultaneously while avoiding the harmful effects of climate change.

Objectives Early detection of Mycobacterial tuberculosis infection (MTB) is pivotal for the treatment of tuberculosis (TB). Background This study was performed to evaluate the performance of BD ProbeTec ET direct detection assay (DTB) against the gold standard culture technique for confirmation of MTB infection. Methods A total of 266 consecutive and non-duplicate clinical specimens for detection of MTB were included in this study. There were 118 respiratory and 148 non-respiratory samples. All samples were tested by microscopy for acid-fast bacillus (AFB), MTB culture and biochemical identification with simultaneous testing by DTB. Results A total of 88 samples (33%) were culture-positive for MTB including 39/118 respiratory, 29/99 fluid and 20/49 tissue samples. DTB sensitivity for respiratory samples was 97% and specificity was 96% with a positive predictive value (PPV) of 93% and negative predictive value (NPV) of 99%. Sensitivity of DTB in fluid samples was 80%, specificity 88%, PPV 69% and NPV 93% whereas sensitivity of DTB for tissue samples was 25%, specificity 90%, PPV 63% and NPV 63%. Of the 50 (56.8%) smear-positive samples, DTB sensitivity was 100% for respiratory, 85% for fluid and 100% for tissue samples. Conclusion DTB performed within acceptable limits for the rapid detection of MTB in respiratory samples compared to fluid and tissue specimens.