Bacteria that are resistant to antibiotics are among the world’s greatest healthcare threats. Researchers at KAIMRC are taking a lead in assessing the threat from multidrug resistance (MDR) in gram negative  bacteria in Saudi Arabia and have carried out a detailed genetic analysis of a particularly concerning MDR infection in a patient in the Kingdom. They describe the bacteria, a strain of Klebsiella pneumoniae, as a serious new public health concern. 

“A couple of years ago we started a nation-wide genome-based surveillance programme focused on characterising clinically important MDR gram negative bacteria,” says Michel Doumith of the Infectious Diseases Research Department at KAIMRC. Doumith explains that a major concern  is bacteria that produce enzymes called beta lactamases. These enzymes are able to break down the ‘beta lactam’ molecules that are the most widely used types of antibiotics. 

In 2018, clinicians identified a multidrug resistant Klebsiella pneumoniae infection in a Saudi patient who had recently returned after undergoing surgery in Egypt. The KAIMRC researchers isolated the bacterium and analysed its genome to gain a better understanding of the mechanisms underlying the drug resistance. 

The bacteria produced a particularly problematic beta lactamase enzyme called a carbapenamase. This is the first instance of a Klebsiella pneumoniae producing carbapenamase (known as a KPC) found in Saudi Arabia.  

One finding of significant concern is that the gene that produces the carbapenamase enzyme is located on a small mobile DNA element called a plasmid. “This gives it the potential to jump into other bacteria that could be more able to thrive in hospital settings,” says Doumith. 

The researchers were able to determine the precise strain of KPC bacteria infecting the Saudi patient, attributing its origin to a strain first observed in Greece. The investigation also identified the genes for a variety of molecules, called virulence factors, that help the bacterium to thrive. 

The ongoing KAIMRC survey has not detected a significant increase in KPC infections, but they have detected a few cases and are currently analysing them in the local and global context

“Our colleagues in the infection prevention and control teams are putting in place measures to isolate patients with carbapenamase-producing bacteria very early to prevent further transmission in hospitals, “ says Doumith. He emphasises the importance of prevention because once they take hold, it has proven very difficult to eliminate these infections from hospitals elsewhere in the world.

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