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Zhu H.,Tianjin Medical University | Jiang Y.,Tianjin Medical University | Watts M.,Center for Infectious Diseases and Microbiology Public Health | Watts M.,University of Sydney | Kong F.,University of Sydney
International Journal of Dermatology | Year: 2015

Background: Pseudoepitheliomatous, keratotic, and micaceous balanitis (PKMB) is an extremely rare condition occurring over the glans in older men who undergo circumcision late in life. Its exact etiology is unknown. Objectives: We report a patient with PKMB that involved the meatus and led to urinary obstruction. Methods: A 57-year-old, circumcised man presented with partial urinary obstruction caused by a thick, nail-like covering on the skin of his glans penis. Based on histology, PKMB was diagnosed. There was no cytological atypia. The patient was treated successfully with topical 5-aminolevulinic acid (ALA) photodynamic therapy (PDT). Results: There was no recurrence after 18 months of follow-up. Treatment with ALA-PDT seems to be effective and well tolerated in PKMB. Conclusions: This case indicates that ALA-PDT may be an effective treatment option for plaque-stage PKMB and thus warrants further investigation. © 2014 The International Society of Dermatology.

Gray T.J.,Institute of Clinical Pathology and Medical Research | Kong F.,Institute of Clinical Pathology and Medical Research | Jelfs P.,Institute of Clinical Pathology and Medical Research | Sintchenko V.,Institute of Clinical Pathology and Medical Research | And 5 more authors.
PLoS ONE | Year: 2014

The identification of rapidly growing mycobacteria (RGM) remains problematic because of evolving taxonomy, limitations of current phenotypic methods and absence of a universal gene target for reliable speciation. This study evaluated a novel method of identification of RGM by amplification of the mycobacterial 16S-23S rRNA internal transcribed spacer (ITS) followed by resolution of amplified fragments by capillary gel electrophoresis (CGE). Nineteen American Type Culture Collection (ATCC) Mycobacterium strains and 178 clinical isolates of RGM (12 species) were studied. All RGM ATCC strains generated unique electropherograms with no overlap with slowly growing mycobacteria species, including M. tuberculosis. A total of 47 electropherograms for the 178 clinical isolates were observed allowing the speciation of 175/178 (98.3%) isolates, including the differentiation of the closely related species, M. massiliense (M. abscessus subspecies bolletii) and M. abscessus (M. abscessus sensu stricto). ITS fragment size ranged from 332 to 534 bp and 33.7% of clinical isolates generated electropherograms with two distinct peaks, while the remainder where characterized with a single peak. Unique peaks (fragment lengths) were identified for 11/12 (92%) RGM species with only M. moriokaense having an indistinguishable electropherogram from a rarely encountered CGE subtype of M. fortuitum. We conclude that amplification of the 16S-23S ITS gene region followed by resolution of fragments by CGE is a simple, rapid, accurate and reproducible method for species identification and characterization of the RGM. © 2014 Gray et al.

Outhred A.C.,University of Sydney | Outhred A.C.,Reference Pathology Laboratory | Jelfs P.,Reference Pathology Laboratory | Jelfs P.,Center for Infectious Diseases and Microbiology Public Health | And 8 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2014

Objectives: Phenotypic drug susceptibility testing (DST) for Mycobacterium tuberculosis takes several weeks to complete and second-line DST is often poorly reproducible, potentially leading to compromised clinical decisions. Following a fatal case of XDR TB, we investigated the potential benefit of using whole-genome sequencing to generate an in silico drug susceptibility profile. Methods: The clinical course of the patient was reviewed, assessing the times at which phenotypic DST data became available and changes made to the therapeutic regimen. Whole-genome sequencing was performed on the earliest available isolate and variants associated with drug resistance were identified. Results: The final DST report, including second-line drugs, was issued 10 weeks after patient presentation and 8 weeks after initial growth of M. tuberculosis. In the interim, the patient may have received a compromised regimen that had the potential to select for further drug resistance. The in silico susceptibility profile, extrapolated from evolving evidence in the literature, provided comparable or superior data to the DST results for second-line drugs and could be generated in a much shorter timeframe. Conclusions: We propose routine whole-genome sequencing of all MDR M. tuberculosis isolates in adequately resourced settings. This will improve individual patient care, monitor for transmission events and advance our understanding of resistance-associated mutations. © The Author 2014.

Wang Q.,Center for Infectious Diseases and Microbiology Public Health | Holmes N.,Center for Infectious Diseases and Microbiology Public Health | Holmes N.,University of Sydney | Martinez E.,Center for Infectious Diseases and Microbiology Public Health | And 5 more authors.
Journal of Clinical Microbiology | Year: 2015

The control of food-borne outbreaks caused by Listeria monocytogenes in humans relies on the timely identification of food or environmental sources and the differentiation of outbreak-related isolates from unrelated ones. This study illustrates the utility of whole-genome sequencing for examining the link between clinical and environmental isolates of L. monocytogenes associated with an outbreak of hospital-acquired listeriosis in Sydney, Australia. Comparative genomic analysis confirmed an epidemiological link between the three clinical and two environmental isolates. Single nucleotide polymorphism (SNP) analysis showed that only two SNPs separated the three human outbreak isolates, which differed by 19 to 20 SNPs from the environmental isolates and 71 to>10,000 SNPs from sporadic L. monocytogenes isolates. The chromosomes of all human outbreak isolates and the two suspected environmental isolates were syntenic. In contrast to the genomes of background sporadic isolates, all epidemiologically linked isolates contained two novel prophages and a previously unreported clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) locus subtype sequence. The mobile genetic element (MGE) profile of these isolates was distinct from that of the other serotype 1/2b reference strains and sporadic isolates. The identification of SNPs and clonally distinctive MGEs strengthened evidence to distinguish outbreak-related isolates of L. monocytogenes from cocirculating endemic strains. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Sadsad R.,Center for Infectious Diseases and Microbiology Public Health | Sadsad R.,University of New South Wales | Sadsad R.,University of Sydney | Sintchenko V.,Center for Infectious Diseases and Microbiology Public Health | And 5 more authors.
PLoS ONE | Year: 2013

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of preventable nosocomial infections and is endemic in hospitals worldwide. The effectiveness of infection control policies varies significantly across hospital settings. The impact of the hospital context towards the rate of nosocomial MRSA infections and the success of infection control is understudied. We conducted a modelling study to evaluate several infection control policies in surgical, intensive care, and medical ward specialties, each with distinct ward conditions and policies, of a tertiary public hospital in Sydney, Australia. We reconfirm hand hygiene as the most successful policy and find it to be necessary for the success of other policies. Active screening for MRSA, patient isolation in single-bed rooms, and additional staffing were found to be less effective. Across these ward specialties, MRSA transmission risk varied by 13% and reductions in the prevalence and nosocomial incidence rate of MRSA due to infection control policies varied by up to 45%. Different levels of infection control were required to reduce and control nosocomial MRSA infections for each ward specialty. Infection control policies and policy targets should be specific for the ward and context of the hospital. The model we developed is generic and can be calibrated to represent different ward settings and pathogens transmitted between patients indirectly through health care workers. This can aid the timely and cost effective design of synergistic and context specific infection control policies. © 2013 Sadsad et al.

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