Pre-clinical research to treat bacterial infection and prevent sight loss

29 June 22

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Researchers are investigating how to reduce severe corneal infection which currently has limited treatment options and can lead to hospitalisation and sight loss.  

Serious cases of microbial keratitis (MK) are caused by Pseudomonas aeruginosa, which has been recognised by the World Health Organisation (WHO) as an essential microorganism requiring research.

When severe, the infection causes cloudiness in the cornea and can lead to hospitalisation or intensive home support.

Current treatment is highly dependent on antimicrobials, which have little effect on bacterial toxins like Exotoxin U (ExoU). There has also been a notable increase in antimicrobial resistance, so there is a pressing need to find alternative ways to treat these toxins.

Led by Professor Stephen Kaye, researchers at the University of Liverpool will now be identifying and repurposing the best inhibitors of the toxin.  

The team will test these and determine the right dosing schedule and their effectiveness, to ultimately see if this method can be used to better manage or treat the condition.

By using inhibitors to reduce bacterial virulence, antimicrobials can eradicate bacteria with less damage to the host and less risk of recurring disease.

If the severity of the infection could be reduced and controlled by these inhibitors, this could reduce hospitalisation rates, dependency on antimicrobials, and ultimately prevent sight loss.

The project could have impact beyond this too, potentially helping to develop other inhibitors for additional bacteria involved in MK (such as Staphylococcus aureus or Streptococcus pneumonia) and could play a role in studies for treatments of acute and ventilator pneumonia.

Previously, Professor Kaye led research to identify compounds such as anti-snake venom that could provide an alternative to antibiotics used to treat MK.

About MK

In the UK there are up to 12,000 cases a year of MK and outcomes often remain poor.

The incidence of Pseudomonas aeruginosa MK is approximately four or five per 100,000 in high income areas and increases to 20 per 100,000 in low income settings.  

In India, the incidence of MK is just under three times more prevalent than in the UK. Corneal opacification (cloudiness of the cornea), which includes MK infection, is the sixth leading cause of global blindness.