Genetic Background to Severe Urinary Tract Infections

Scientists at Lund University in Sweden have found a gene that appears to lie behind many of the most severe urinary tract infections. The study is published on September 5 in the online, open-access journal PLoS ONE.

It is well known that certain people have a tendency to develop urinary tract infections again and again. These infections often start in childhood. In serious cases they can lead to infections of the renal pelvis, which ultimately can damage the kidneys so severely that the patient will need dialysis or a kidney transplant.

Doctors have long been hoping for a method for early detection of the small group of people who are in the risk zone for renal pelvis infections. If they could single them out early, it would be unnecessary to subject all children who get a urinary tract infection to a thorough and sometimes unpleasant examination. Instead, such examinations and any preventative treatment could be reserved for those who really need it.

“Many research teams have long been looking for a genetic background to the disease. We have found a gene that could be used as a risk marker and a method for singling out the susceptible group,” says researcher Ann-Charlotte Lundstedt and Professor Catharina Svanborg.

The gene in question produces a protein that is involved in the immune defence system. It regulates the migration of white blood corpuscles to the kidneys and their work with neutralizing infectious bacteria. The Lund team has previously shown that the gene protects against renal pelvis inflammation in animal experiments. Now, in studies of children and adults with recurrent renal pelvis infections, they have also shown that mutations of this very gene are much more common in kidney patients than in healthy control individuals.

“We also saw that even patients without genetic changes have low levels of this protein. Therefore, a combination of a genetic examinations and a protein measurement could be a good way to find those who are most clearly in the risk zone,” says Catharina Svanborg.