In a paper in the Journal of Infectious Diseases, a team of University of Michigan researchers have demonstrated that bacteria can form antibiotic-resistant clumps in a short time, even in a flowing liquid such as the blood.
The researchers made the discovery by building a special device that closely simulates the turbulence and forces of blood flow, and adding a strain of bacteria that's a common cause of bloodstream infections.
Tiny aggregates, or clumps, of 10 to 20 bacteria formed in the flowing liquid in just two hours -- about the same time it takes human patients to develop infections.
The researchers also showed that these clumps only formed when certain sticky carbohydrate molecules were present on the surface of the bacteria. The clumps persisted even when two different types of antibiotics were added -- suggesting that sticking together protects the floating bacteria from the drugs' effects.
Reference: Journal of Infectious Diseases, Volume 206, Issue 4, Aug. 15, 2012 -- pp. 588-595
For further details see University of Michigan Health System.