Soaring levels of antibiotic resistance have driven a 40 per cent rise in prescriptions of drugs which are only used as a last hope, new figures show. NHS statistics reveal increasing use of the medication which is so toxic that it is only used when standard antibiotics have failed. Experts said the disclosures reflect a "terrifying" crisis which could mean that in future patients suffer lethal consequences from routine procedures. The figures revealed by the Bureau of Investigative Journalism show that in just one year, prescriptions of colistin have risen from 346,000 to 485,000 daily doses. The drug is used when patients do not respond to standard antibiotics such as penicillin. The antibiotic has been used widely in farming, mainly as a growth-promoter. But in recent years, fears about antibiotic resistance have resulted in restrictions in its use. China has banned the drug as an animal feed additive and the European Commission has recommended that use in agriculture is slashed by two thirds. Yet the investigation reveals that last year, the UK's Veterinary Medicines Directorate licensed three new products containing colistin for use on British farms. Scientists last night said the decision was "utter madness" and could mean the "last hope" drug became useless in humans within a decade. In recent years, the drug has already found to be resistant in a number of cases, with a recent case involving a woman who died from septic shock in Nevada after tests showed colistin could not stem her bloodstream infection. Currently, such cases are rare. But if current trends continue, colistin resistance will spread in England, with dire consequences for human health, experts warned. In the UK, at least 12,000 people die from antibiotic-resistant bugs each year, experts estimate - more than die of breast cancer. Dr Michael Weinbren, a consultant in infectious diseases and infection prevention and control at Chesterfield Royal Hospital NHS Foundation Trust said: "The one thing you can be sure of is that the organisms will develop resistance." "It's Darwinian. It's as sure as eggs are eggs. Colistin resistance will become more common. When you're down to one class of antibiotic, you've got to be worried. You've got to be terrified and we need to be doing something about this." The term superbug refers to an infection which has become resistant to the antibiotics usually used to treat it. Some superbugs have become resistant to virtually all antibiotics, and genes and enzymes have now developed which can turn bacteria found naturally in our gut into resistant superbugs. Chief medical officer Dame Sally Davies has said that the threat posed by antibiotics ranks alongside terrorism and could mean a simple cut or infection could prove fatal. A group of antibiotics known as carbapenems are currently used as a last ditch treatment for superbugs which aren't affected by other medicines. This family of bugs, known as carbapenem-resistant Enterobacteriaceae (CRE), includes evolved versions of common bacteria such as E.Coli and Klebsiella. Epidemiologists have called CRE ‘the nightmare bacteria' because 40 to 50 per cent of people who suffer a bloodstream infection from them die. When a patient gets a CRE infection, colistin is one of few options doctors have left that has a chance of working. One of the UK's leading microbiologists said doctors were prescribing more colistin because of rising resistance to standard antibiotics. Professor Peter Wilson, consultant microbiologist at University College Hospital London said: "When you've got an infection you know is resistant to carbapenems you use colistin. It's not an antibiotic doctors would use out of choice." The reason colistin still works is partly because despite being created in the 1950s, it was shelved soon after it was introduced because it is toxic to the kidneys and nervous system. Bacteria did not develop resistance to colistin because they were not exposed to it. Years later, when all newer antibiotics began to fail, colistin was brought back into use. As a result, more patients are now suffering serious kidney problems Dr Weinbren said. "Resistance means we're being forced to use drugs with significant side effects. For some patients, you just don't have a choice anymore.' The drug is also routinely given to treat cystic fibrosis patients who suffer repeat infections from resistant pseudomonas bacteria and other infections. Increasing colistin resistance was a "matter of life and death" for such patients, warned the Cystic Fibrosis Trust. Stuart Elborn, Professor of Respiratory Medicine at Imperial College, said: "Resistance means we'd lose one of our most effective antibiotics for prevention and treatment of infection in cystic fibrosis patients." The rise in colistin prescriptions can also be explained by doctors using higher doses of the drug - because once a bug has developed a level of resistance, more of the drug is needed to effectively kill it, experts said. Professor Timothy Walsh, one of the scientists who originally discovered colistin resistance, said the decision to license new products containing the drug for use on British farms was "sheer, utter madness". Colistin is likely to become useless as a drug within 10 years if its usage in veterinary medicine is not stopped, he said, calling for it to be banned in husbandry and agriculture. In late 2015 the discovery of a gene which makes bacteria resistant to colistin – called MCR-1 – sparked worldwide alarm. The gene was first discovered in pigs and humans in China but has now been found in the UK, elsewhere in Europe as well as in the US, and parts of Asia and Africa. Scientists believe rampant use in agriculture is why the MCR-1 gene developed and spread around the globe, breeding untreatable superbugs. The Government last year pledged to reduce antibiotic use in livestock and fish farming by about 20 per cent by next year, promising to "introduce strict oversight of the use in animals of antibiotics which are critical for human health – including supporting restrictions or even bans where necessary." A Government spokesperson said: "We are leading a national and international fightback against drug resistant infections. We have a comprehensive strategy that includes tackling the bugs in humans and animals, and preventing infections in the first place through good hygiene. Education on how to use antibiotics appropriately is essential and the National Institute for Health and Care Excellence published guidance recently to help everyone understand how to do this. UK doctors are making great strides in cutting antibiotic prescriptions. In animals, there are tight restrictions on the use of colistin and it is only used as a last line treatment where no other alternative exists. Defra continues to promote good hygiene and animal care to prevent the need for antibiotics to be used in livestock."
