Publications by authors named "Joanne Malkin"

Background: Although tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination.

Methods: In series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay.

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We have developed a novel real-time PCR assay to identify and perform preliminary genotyping of mycobacteria in a manner tailored to our local service. Within a single thermocycler run, mycobacterial 16S rDNA and the Mycobacterium tuberculosis global lineage-defining RD750 polymorphism are targeted in separate reaction tubes, each of which includes both TaqMan and SYBR Green chemistries. The results of this 16S-RD assay differentiate M.

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Article Synopsis
  • Resuscitation-promoting factors (Rpfs) are proteins produced by Mycobacterium tuberculosis that help the bacteria grow, and their influence on human infection was previously unclear.
  • In a study of tuberculous sputum samples, it was found that a significant majority (80-99.99%) of Mtb cells could be detected only when Rpfs were present, indicating these cells are not easily observable through standard cultivation methods.
  • Additionally, during chemotherapy, the proportion of Rpf-dependent Mtb cells increased, suggesting these bacteria exhibit a form of resistance that could affect treatment outcomes and disease transmission.
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We present a case of Mycobacterium kansasii olecranon bursitis in a woman with known immunosuppression secondary to the treatment received for her Behçet's disease. We found only one other case report of olecranon bursitis caused by M. kansasii in the literature, which, unlike our case, presented in an immunocompetent adult following trauma.

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Today, PCR using broad-range primers is being used increasingly to detect pathogens from resected heart valves. Herein is described the first case of multivalve infective endocarditis where 16S rDNA PCR was used to detect a single pathogen from two affected valves in a 61-year-old man. Triple heart valve replacement was required despite six weeks of appropriate antimicrobial therapy.

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A case of purpura fulminans (PF) in a child secondary to infection with meticillin-sensitive Staphylococcus aureus (MSSA) encoding the Panton-Valentine leukocidin (PVL) toxin genes is presented. Occasional cases of PF have been documented secondary to S. aureus infection in adults, but, to the authors' knowledge, not in children.

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