A new study by researchers at Uppsala University sheds light on how a previously observed phenomenon called heteroresistance might be a stepping stone for bacteria to develop full-blown antibiotic resistance. This is the first time a direct link between the two has been established.
"Heteroresistance is quite common, and we've shown it occurs with at least 10 different antibiotic classes. Patients carrying heteroresistant bacteria during antibiotic treatment have a higher risk of death and intensive care unit admission compared to those with susceptible bacteria," explains Dan I. Andersson, lead researcher and Professor of Medical Bacteriology at Uppsala University. "If heteroresistance paves the way for full resistance, then we need to find better ways to control its occurrence and effects."
Heteroresistance is a state where a majority of bacteria in a population are susceptible to antibiotics, but a small subpopulation exhibits resistance. These resistant bacteria have more copies of resistance genes, making them grow slower. However, the new study, published in Nature Communications, demonstrates how bacteria in lab settings can acquire additional resistance mutations, regaining faster growth. This suggests that heteroresistance can act as a springboard for bacteria to evolve towards stable antibiotic resistance.
"There's always a chance we might be wrong," acknowledges Andersson, "but based on our lab observations, there's no reason to believe this wouldn't happen in patients or animals. This is a significant finding for understanding how bacteria develop resistance."
Andersson anticipates this discovery to lead to more clinical studies and increased detection of heteroresistance in clinical labs. He emphasizes the continued importance of responsible antibiotic use in healthcare: "We need to use antibiotics smartly, only when necessary and at the right time. This helps us prolong the effectiveness of existing antibiotics and buys time for developing new ones."
0 Comments