Doctors have reported an alarming number of MRSA patients being attacked by a life-threatening flesh-eating infection in the US. The patients seem to have caught a new form of the notorious "superbug" outside hospital. Several developed complications and needed lengthy stays in intensive care and reconstructive surgery. The doctors, who identified 14 such patients during 15 months at their medical centre in Los Angeles County, California, warn in the New England Journal of Medicine that clinicians may not recognise that necrotising fasciitis, as the flesh-eating condition is properly known, can be caused by MRSA. That could mean patients not being given the appropriate treatment - even in areas where MRSA is endemic - since such attacks are normally caused by a different bug. Although the cases still seem only to have occurred in one place, they are the latest bad news about MRSA to emerge from the US, where infections seemingly acquired outside hospital are now a common and serious problem. They often involve the skin, especially in children, and may mean that people need hospital treatment. People who have been in jail, have attended gay massage parlours or been involved in close-contact sport are among those in other countries who have developed MRSA outside hospitals. Health officials in Britain, who may just be turning the tide of infection in hospitals, are desperate to ensure that the same thing does not happen here. MRSA, forms of the Staphylococcus aureus bacterium resistant to antibiotics in the methicillin class, emerged as a problem in hospitals in the 1960s. The bacterium exists harmlessly on the skin and in the nose of around a third of healthy people, but can cause severe life-threatening infec tion in people whose immune system is compromised. Its effect, until it gets into the bloodstream and poisons it, is often quite localised. But necrotising fasciitis, which attacks the fatty layer of tissue beneath the skin, is normally associated with quite another family of bacteria, the streptococci, which often spread quickly. The new cases involved people who had a history of drug injecting, previous MRSA infection, HIV or other conditions such as diabetes, hepatitis and cancer. Unusually, all the patients survived the necrotising fasciitis, which typically kills a third of those who develop it. The authors concede too that the problem might be caused by a very local specific strain of MRSA, and that other toxic organisms might be involved. But they conclude that there is an "emerging clinical entity" with the potential to cause rapidly progressive disease that is indistinguishable from necrotising fasciitis caused by other organisms. "Staphylococcus aureus has been a very uncommon cause of necrotising fasciitis, but we have recently noted an alarming number of these infections caused by community associated methicillin-resistant S. aureus (MRSA). "The new MRSA has not yet been identified in this country, according to the government watchdog body, the Health Protection Agency, but it is carefully monitoring all suspect cases, including patients who have not recently had surgery or been in hospital, where the bug is still more common, or who have been on antibiotics for a long time. Angela Kearns, head of the agency's Staphylococcus reference laboratory, said that the risk of contracting MRSA in the community ìremains extremely smallî. She added that the agency was ìunaware of any cases of necrotising fasciitis associated with C-MRSA in the UK at this time."