London School of Hygiene & Tropical Medicine

A woman from the USA has died of infection from a strain of Klebsiella pneumonia that was resistant to all 26 available antibiotics in the United States, as reported by the US Centers for Disease Control and Prevention (CDC).

The woman returned to the state of Nevada in August with an infection in her hip, following an extended period in India. It is believed she picked up the multi-resistant strain through a wound infecting her bone and hip, whilst in India where she was previously hospitalised for a broken leg. Typically found in the gut, K. pneumoniae does not usually cause harm, but in this case the bone infection caused severe inflammation, which ultimately caused the woman to die from septic shock.

Doctors found that none of the 26 antibiotics available in the US were able to treat the infection, including carbapenems and colistin, often referred to as the 'drugs of last resort.' After tests conducted by the CDC, the bacterium was found to have low levels of resistance to fosfomycin, but the antibiotic is not approved in the US for this type of infection.

How significant is this report and how concerned should we be? Dr Richard Stabler, Associate Professor in Molecular Bacteriology at the London School of Hygiene & Tropical Medicine, explains:

"This CDC report is alarming, but sadly not unsurprising. Cases such as these will become more common unless action is taken now. Klebsiella pneumonia is normally found in the mouth, skin and intestines, and is often harmless. However, recently this bacterial species has been acquiring resistance to many classes of antibiotics.

"Carbapenems have been the drug of last resort but resistance to this class of drugs by Klebisella (and other bacteria) have generated a group of organisms called carbapenem resistant Enterobacteriaceae (CRE). The loss of this last and vital class of antibiotics means that in many countries colistin, and other polymyxins, are now the final effective weapons with which to fight these multi-antibiotic resistant organisms. Worryingly this strain was resistant to even these powerful antibiotics.

"Thankfully this was an isolated case due to effective infection control and testing. However, the fact that the bug was resistant to all available US antibiotics demonstrates that the post-antibiotic era could be on our doorstep. Klebsiella pneumonia and CRE are an ever-increasing problem in the UK. With the increasing financial pressures on the NHS it is vital to maintain vigilance against these superbugs."