Antimicrobial treatment can help avoid sepsis in pneumonia patients

The study gives information on the early stages of infectious illness and the possibilities for pneumococcal septicaemia prophylaxis. Antimicrobial treatment is used to kill or prevent the growth of microorganisms such as bacteria, fungus, and protozoans. The study, published in the journal Nature Microbiology, reveals how the bacteria that causes pneumonia replicates within our immune system during the early stages of infection.

Professor Marco Oggioni of the University of Leicester’s Department of Genetics and Genome Biology led a team of researchers who discovered that the bacterium Streptococcus pneumoniae (pneumococcus) replicates within a specific subset of immune cells in our bodies – a subset of splenic macrophages – before causing invasive and often fatal disease.

This internal replication shields the bacteria from being destroyed by other immune cells as well as the activity of the most regularly used antibiotics, including those indicated for community-acquired pneumonia in the United Kingdom.
The study also found that antibiotic therapy aimed especially at stopping this phase of intracellular replication can avoid the formation of pneumococcal septicaemia, which is frequent in many pneumonia patients.

Pneumonia is one of the primary causes of infectious illness death, and it is more frequent in some vulnerable populations, such as the very young and the elderly. “Understanding infections is vital in knowing how to effectively treat an illness,” explains Professor Marco Oggioni, an honorary consulting biologist at Leicester Hospitals.

“Our findings demonstrate that we can treat potentially fatal illnesses more successfully with readily accessible drugs.” We believe that by determining how and where bacteria cause disease, we can send a powerful message to the medical community, encouraging the modification of presently used medicines, which might lead to a decrease in disease burden and death in the UK and worldwide.”

Using confocal microscopy, the researchers conducted studies on a number of creatures. This enabled them to label and visualise various immune cells as well as the invading bacteria. As part of this work, the team created a new model that makes use of pig spleens that have been processed for food. This allowed them to examine infection in a human-like model without having to infect a real animal.