The LightCycler SeptiFast Test MGRADE (Roche Diagnostics), SepsiTest (Molzym Molecular Diagnostics) and IRIDICA BAC BSI assay (Abbott Laboratories) analyse whole blood samples to identify bacterial and fungal DNA. The tests aim to identify the causes of infection much quicker than traditional microbiology techniques which require blood samples to be incubated and cultured before pathogens can be identified.

Sepsis is a common and potentially life-threatening condition triggered by a bloodstream infection. Bacterial infections are the most common cause of sepsis, but it can also be caused by fungal infections and less commonly by viral infections. People who are suspected of having sepsis are usually given broad spectrum, high potency antibiotics that include one or more drugs that have activity against all likely bacterial or fungal pathogens.

However, despite being clinically effective, increased use of broad spectrum antibiotics is associated with the development and spread of antimicrobial resistance, leading to a heightened risk in the future that we may not be able to treat infections effectively. It is also associated with an increased risk of patients developing a second infection caused by opportunistic microorganisms resistant to the drugs used in treating the first infection (superinfection). Rapidly detecting bacterial and fungal DNA may reduce the length of time broad spectrum antibiotics and antifungals are used and allow targeted treatment earlier in the care pathway.

Use of these tests could enable earlier targeted treatment for patients and reduce the use of broad-spectrum antimicrobials which could help reduce future antimicrobial resistance.

Professor Carole Longson MBE, NICE Health Technology Evaluation Centre Director, said: “Rapid molecular tests that can identify the cause of an infection in hours rather than the days typically needed for traditional microbiology tests could ensure the most appropriate antibiotics are used much earlier. This in turn could improve outcomes for patients with suspected bloodstream infections, as well as help to reduce the spread of resistant microbes.

“The independent Diagnostics Advisory Committee concluded that, although the tests show promise, there is currently not enough evidence to recommend their routine adoption in the NHS. They felt the tests may offer clinical benefit by providing results more quickly but there was currently too much uncertainty in their accuracy for clinicians to be able to use them as the basis for clinical decision-making in people with suspected bloodstream infections, who can be acutely unwell.

“The Committee therefore decided that further research should be encouraged to provide robust evidence, particularly around demonstrating the value of using the test results in clinical decision-making.”

The diagnostics guidance on the LightCycler SeptiFast Test MGRADE, SepsiTest and IRIDICA BAC BSI assay for rapidly identifying bloodstream bacteria and fungi is available on the NICE website.

Ends

For more information call the NICE press office on 0300 323 0142/ pressoffice@nice.org.uk or out of hours on 07775 583 813.

Notes to Editors

About sepsis

1. Sepsis is diagnosed where there is evidence of systemic inflammation, in addition to a documented or presumed infection. Systemic illness often occurs when bacteria invade normally sterile parts the body. One example of this is the invasion of bacteria or fungi into the bloodstream (bloodstream infection), a process which often causes an inflammatory immune response.
2. Bacterial infections are the most common cause of sepsis and bloodstream infection; however they can also be caused by fungal infections, and less commonly by viral infections.
3. The most common sites of infection leading to sepsis are the lungs, urinary tract, abdomen and pelvis. Other sources of infection leading to sepsis include skin infections (such as cellulitis), post-surgical infections and infections of the nervous system (such as meningitis or encephalitis).
4. Patients who are currently or have recently been hospitalised, are at risk of acquiring a healthcare associated infection and are therefore at increased risk of sepsis and bloodstream infection. It is thought that the increasing number of invasive procedures such as catheterisation, immunosuppressive therapy, antibiotic therapy and life support measures has resulted in an increase in healthcare associated bloodstream infections.
5. The bacteria most commonly associated with bloodstream infection in adults include gram negative species such as Escherichia coli, Klebsiella species and Pseudomonas species, and gram positive species such as Staphylococcus aureus, non-pyogenic streptococci, Enterococcus species and Streptococcus pneumoniae.
6. The types of pathogens causing bloodstream infection can differ in children as compared to those isolated from adults with bloodstream infection and can include Neisseria meningitidis. In addition polymicrobial infection and anaerobic bacteraemia are thought to occur less frequently amongst children.

 About the NICE Diagnostics Assessment Programme 

1. For further information about the NICE diagnostics assessment programme see Developing NICE diagnostic technologies guidance  
2. Topics to be considered by the Programme are routed through the related Medical Technologies Evaluation Programme. Further information about this can be found at Developing NICE medical technologies guidance