Researchers at Karolinska Institutet in Sweden have succeeded in explaining how the body protects itself against urinary tract infections; with the help of an endogenous antibiotic.
The discovery, which is being published in the prestigious scientific journal Nature Medicine, revolutionises our understanding of how the body defends itself against bacterial attack in the urinary tract.
"Antibiotic-resistant bacteria are a growing problem," explains research leader Professor Annelie Brauner. "As the development of resistance to the body's own antibiotic is very rare, it can be used as an alternative or a complement to conventional antibiotic medication."
Urinary tract infection is currently one of the ten most common reasons for outpatient visits. Up to 60 % of all women develop a urinary tract infection at one time in their life, and of these, 20 % have recurrent problems with it. Children less often have urinary tract infections but when the kidneys are involved up to 40 % get scarring of the kidneys.
It was previously thought that the urinary tract was kept sterile by the flow of urine, which stops bacteria from lodging in the mucus membrane of the urinary tract. However, scientists at the Department of Microbiology, Tumour and Cell Biology have now shown that an endogenous peptide is of critical significance to the prevention of urinary tract infection, a finding that paves the way for radical new forms of treatment.
The researchers measured levels of the antibacterial peptide LL-37 in the urine of healthy children and children with a urinary tract infection. They found that the levels were very low in the former group but high in the latter. Using cultivated human kidney and urinary bladder cells they were then able to identify which cells in the body produce LL-37.