Wednesday, 6 September 2017

MRSA survival chances predicted by DNA sequencing


Sequencing the DNA of the MRSA superbug can accurately identify patients most at risk of death and could help medics develop new treatments as we move towards personalised medicine. MRSA is a Staphylococcus aureus bacterium that has become resistant to most types of antibiotics, and up to 20 per cent of patients with invasive infections die.

Whilst S. aureus is a common bacterium that lives on the skin, if it gets inside the body through a cut it can cause septicaemia (blood poisoning). This potentially life-threatening infection affects thousands of patients every year in the UK.

There are two main strains of MRSA found in UK hospitals, called CC22 and CC30.

For the first time a team of scientists led by the Milner Centre for Evolution at the University of Bath were able to study blood samples from around 300 patients with septicaemia, looking at how the different MRSA strains behaved and assessing their lethality.

They examined the genetic code of the infecting MRSA bacteria, and paired this information with individual risk factors for each patient, including age, presence of any other illnesses, and noted whether the patient was still alive after 30 days of the infection and if deceased whether MRSA contributed to their death.

Paired together this information allowed the team predict with high accuracy the individual's probability of surviving the MRSA infection.

See:

Mario Recker, Maisem Laabei, Michelle S. Toleman, Sandra Reuter, Rebecca B. Saunderson, Beth Blane, M. Estee Török, Khadija Ouadi, Emily Stevens, Maho Yokoyama, Joseph Steventon, Luke Thompson, Gregory Milne, Sion Bayliss, Leann Bacon, Sharon J. Peacock, Ruth C. Massey. Clonal differences in Staphylococcus aureus bacteraemia-associated mortalityNature Microbiology, 2017; DOI: 10.1038/s41564-017-0001-x

Posted by Dr. Tim Sandle