Scientists have discovered a trigger to a deadly chain of events that ends in amputations and death in patients with severe meningococcal disease. Their findings could now be used to help develop treatments to prevent such terrible outcomes for these patients.

Infection from meningococcal bacteria is the leading cause of meningitis and septicaemia in the UK and Ireland. Around one in ten people affected will die and a third of survivors will be left with after-effects, some as serious as amputations, brain damage, hearing loss and blindness. One deadly complication of meningococcal infection is purpura fulminans where blood clots develop in the bloodstream. These block small blood vessels and cause tissue to die. This is why patients with meningococcal septicaemia lose fingers, toes and entire limbs. Clotting can also damage vital organs.

In a study funded in part by charity Meningitis Research Foundation (MRF) and published in PLOS Pathogens, scientists from Institut Necker-Enfants-Malades (INSERM/CNRS unit at the University Paris Descartes), discovered that when the meningococcal bacteria bind to the lining of our blood vessels, a molecule called ADAM10 becomes active and prevents our body’s natural ability to stop uncontrollable blood clotting.

Xavier Nassif, from Institut Necker-Enfants-Malades, Paris, said, “We knew that purpura fulminans tends to be extreme in patients with meningococcal disease, which suggested that meningococcal bacteria intensify the clotting process in a unique way. Our research has identified a key step in the process which enables purpura fulminans to develop in patients with meningococcal disease. This new understanding of the role that ADAM10 has to play could help the development of new therapeutics.”