Category Microbiology
You are what you eat – or should our gut microbiome be considered an important body system in its own right?
Guest posting: Assoc. Prof. Josh Davis, Principal Research Fellow/NHMRC Career Development Fellow, Menzies School of Health Research, Senior Staff Specialist Infectious Diseases Physician, John Hunter Hospital, Conjoint Professor School of Medicine and Public Health, University of Newcastle The diverse bacterial communities which live in our gastrointestinal tract (primary in the colon), are collectively known as the “gut microbiota” and their collective […]
Micro lab comments: candidaemia and candiduria
Candidal bloodstream infection represents a high risk infection, even for immunocompetent patients. Mortality is significant even for IV line-associated candidaemia. Blood cultures are seldom contaminated by fungi and any patient with an isolate must be subjected to careful clinical assessment. Our comment serves to give a few reminders that follow on from the liaison between the […]
Microlab comment: beta-haemolytic streptococci isolated from blood
Here is another one used for uncomplicated bloodstream infection events: Infections due to these species of streptococci are usually rapidly responsive to appropriate antibiotic therapy which can be of short duration with no minimum IV requirement as endocarditis is not a usual consideration. Penicillin resistance has not been documented and flucloxacillin is just as active (see […]
Micro comments unpacked: Gram negative bacteraemia
Here is an example comment from Pathology North which is added to positive blood culture reports when a Gram negative coliform species ( Enterobacteriacae eg. E. coli) has been isolated: The comment’s rationale is to promote short course treatment and also to prompt oral antibiotic switching in a timely manner. It also prompts consideration of source […]
Essential clinical care of Staphylococcus aureus bloodstream infection (SAB)
Updated 8/5/20. A. Healthcare-associated events (2018, HNE LHD ) 60 healthcare-associated SAB cases occurred with 7% due to methicillin-resistant Staphylococcus aureus (MRSA) and age-adjusted 30 day mortality of 9%. SAB relapse within 15-90 days occurred in 2.1% of adult events 7% of paediatric events. Principle sites common: ● Vascular access device (e.g. intravenous cannula, central […]
Why do Gram positive and Gram negative bacteria show different antibiotic susceptibility patterns?
The terms Gram positive and Gram negative are commonly used to describe bacteria. The main difference between the two is the structure of their cell wall which changes their susceptibility to different antibiotics. The separation also loosely fits the location of these organisms in the body – Gram negative organisms predominate in the bowel (eg. […]
AIMED - Let's talk about antibiotics 
Pathology stewardship – an essential element of AMS
Poor antimicrobial prescribing decisions often are triggered by laboratory results that create red herrings or worse. Inappropriate/ poor specimen collection and/or a request form that provides no context to the investigation often sets the ball rolling. Inappropriate workup and reporting of contaminant or colonising isolates may then follow (it may be impossible for the lab […]