Bacteria such as Escherichia coli (E. coli) are known to hide during an infection by encasing themselves in extracellular matrix containing amyloid proteins and cellulose. When they grow like this, clusters of bacteria are called biofilm and they are hard to detect and partly resistant to antibiotics.
The same bacteria are known for causing urinary tract infections (UTIs), which often turn out to be a recurrent illness. UTIs are very common and about 50 % of women have had such an infection at some point in their life. Uncomplicated cases of UTIs are treated with antibiotics, but in case of chronic and recurrent UTI, antibiotic resistance is an important problem. If antibiotics cannot combat the bacteria, kidney infections or even sepsis can occur and cause serious complications.
Researchers at Karolinska Institutet in Sweden asked the question if the reason for chronic and recurrent UTI might be related to the extracellular matrix surrounding E. coli, rather than the bacteria themselves. Therefore, they used an EbbaBiolight-like Molecule to detect cellulose, which humans do not produce, but which is an abundant component in E. coli biofilm. So, if cellulose is detected in a human urine sample, it is likely to be of bacterial origin.
A short video clip explains the significance of a test for cellulose in urine indicating the presence of a biofilm related infection.
The researchers collected urine samples from Karolinska University Hospital and tested the urin for presence of cellulose using a rapid and simple method. Using an EbbaBiolight-like Molecule, an assay was developed which allowed biofilm screening of urine samples within 45 min and it was shown that about 15 % of urine samples contained cellulose and were therefore related to biofilm forming E. coli.
Linking biofilm-related infections to recurrent UTIs is an important step for future diagnostic efforts as this information can help to determine the correct course of treatment and thereby help to avoid serious complications that can be harmful to patients.