Shining light on bone infections

A combination of drugs and light offers a welcome new approach in the treatment of post-op bone infections.

The bone infection osteomyelitis, can occur after hip replacements and other surgical procedures. These infections are typically treated with a four to six week course of antibiotics, with or without surgical intervention to remove damaged tissue and improve blood flow. Stuart Bisland and colleagues at the University of Toronto, Canada, have shown that a combination of drugs and light might be just as effective.

Bisland coated short titanium wires with biofilms of Staphylococcus aureus and the wires were implanted into the tibia of the back legs of rats. The particular S. aureus strain contained a bioluminescent lux  gene. This allowed the living bacteria to be detected from outside the animal. 

The procedure used is known as photodynamic therapy or PDT. A photosensitising drug is administered which makes the bacteria more susceptible to light when it is later applied. Bioluminescence levels fell as quickly as 24 hours after PDT treatment.

’The versatility and potency of PDT against many types of microorganism and the lack of resistance associated with repeated use warrant further investigation as an alternative therapy to antibiotics’ says Bisland.

Michael Smith