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This prospective cohort study was conducted to compare the accuracy of QuantiFERON®-TB (QFT) Gold In-Tube test and tuberculin skin test (TST) in diagnosing tuberculosis (TB) in predominantly bacille Calmette–Guerin-vaccinated children with a high incidence of malnutrition. The sensitivity of the QFT versus the TST was 69.6% versus 52.9% for WHO-defined TB, with specificity of 86% versus 78.3%, respectively. The concordance of the TST and QFT was 79% overall (? = 0.430), 62.5% in those with WHO-defined TB and 85.7% in those without TB. Majority of the QFT+/TST ? discordance was seen in children with TB, whereas majority of the TST+/QFT ? discordance was seen in those without TB. The TST was more likely to be negative in children with moderate-to-severe malnutrition (P = 0.003) compared to the QFT, which was more likely to be positive in younger children. The significantly better performance of the QFT in malnourished children and those at younger ages supports its use for TB diagnosis in these subpopulations.
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Purpose: Hospital outbreaks are observed increasingly worldwide with various organisms from different sources such as contaminated ultrasound gel, intravenous (IV) fluids and IV medications. Among these, ultrasound gel is one of the most commonly reported sources for Burkholderia cepacia complex (Bcc) outbreaks. In this study, we describe our experience on investigation and the management of Bcc bacteraemia outbreak due to contaminated ultrasound gel from a tertiary care centre, South India. Materials and Methods: Over a 10-day period in October 2016, seven children in our Paediatric intensive care unit (ICU) were found to have bacteraemia with Bcc isolated from their blood culture. Repeated isolation of the same organism with similar antimicrobial susceptibility pattern over a short incubation period from the same location, confirmed the outbreak. An active outbreak investigation, including environmental surveillance, was carried out to find the source and control the outbreak. Isolates were subjected to multi-locus sequence typing (MLST) and global eBURST (goeBURST) analysis. Results: Environmental surveillance revealed contaminated ultrasound gel as the source of infection. MLST and goeBURST analysis confirmed that the outbreak was caused by a novel sequence type 1362 with the same clonal complex CC517. The outbreak was controlled by stringent infection control measures, withdrawal of contaminated ultrasound gel from regular usage and implementing the practice of using ultrasonogram (USG) probe cover for USG screening and guided procedures. Conclusion: This report highlights the importance of early identification of an outbreak, prompt response of the ICU and infection control teams, sound environmental and epidemiological surveillance methods to identify the source and stringent infection control measures to control the outbreak. Contaminated ultrasound gel can be a potential source for healthcare-associated infection, which cannot be overlooked.
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Background & objectives: Bacillary dysentery caused by Shigella spp. remains an important cause of the crisis in low-income countries. It has been observed that Shigella species have become increasingly resistant to most widely used antimicrobials. In this study, the antimicrobial resistance, virulence and plasmid profile of clinical isolates of Shigella species were determined. Methods: Sixty clinical Shigella isolates were subjected to whole-genome sequencing using Ion Torrent platform and the genome sequences were analyzed for the presence of acquired resistance genes, virulence genes and plasmids using web-based software tools. Results: Genome analysis revealed more resistance genes in Shigella flexneri than in other serogroups. Among ?-lactamases, blaOXA-1was predominantly seen followed by the blaTEM-1B and blaEC genes. For quinolone resistance, the qnr S gene was widely seen. Novel mutations in gyr B, par C and par E genes were observed. Cephalosporins resistance gene, blaCTX-M-15 was identified and plasmid-mediated AmpC ?-lactamases genes were found among the isolates. Further, a co-trimoxazole resistance gene was identified in most of the isolates studied. Virulence genes such as ipaD, ipaH, virF, senB, iha, capU, lpfA, sigA, pic, sepA, celb and gad were identified. Plasmid analysis revealed that the IncFII was the most commonly seen plasmid type in the isolates. Interpretation & conclusions: The presence of quinolone and cephalosporin resistance genes in Shigella serogroups has serious implications for the further spread of this resistance to other enteric pathogens or commensal organisms. This suggests the need for continuous surveillance to understand the epidemiology of the resistance.
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Purpose: Sepsis is a significant cause of morbidity and mortality amongst neonates. Klebsiella pneumoniae is a common cause of nosocomial outbreaks causing bacteraemia and having potential of acquiring plasmids enhancing antimicrobial resistance. In the present study, we investigate K. pneumoniae outbreak causing bacteraemia amongst neonates over a span of 2 months. Isolates were characterised for antimicrobial resistance, virulence, molecular typing for clonality and plasmid typing for transmission dynamics, and patient outcome was investigated. Methods: Thirteen isolates of K. pneumoniae were obtained during October–November 2016. Antimicrobial susceptibility testing was performed, and multiplex polymerase chain reaction (PCR) for ?-lactamases and PCR for ompK35 and ompK36 were performed. To study hypervirulence, string test and PCR for rmpA and rmpA2 were performed. Multilocus sequence typing and Inc plasmid typing were carried out to study transmission dynamics. Results: Amongst 13 isolates, all isolates harboured blaSHVand blaTEM; 12 isolates carried blaCTX-M-1. ompK35 was present in all, but ompK36 was absent in 12 isolates. Ten isolates belonged to ST48, 6 amongst which contained IncFII (K) plasmid. One isolate each belonged to ST29, ST111 and ST2647 (novel clone). None of the isolates was hypervirulent. Conclusion: Extended-spectrum ?-lactamase K. pneumoniae is commonly seen in Indian hospitals and main mechanisms being production of SHV, TEM and CTX-M enzymes as seen in the present study. Outer membrane porins contribute significantly to antimicrobial resistance. Emergence of new clones such as ST2647 implies continuous evolution of the organism and also potential for rapid genetic recombination leading to multidrug resistance. Outbreaks amongst neonates lead to fatal outcome, and stringent hospital infection control is necessary.