Most people with cystic kidneys eventually develop kidney failure, but when that happens is different for everyone. Nephrologist Mahdi Salih of the Erasmus University Medical Center suspects that the precipitation of salt crystals in the kidneys can give an indication of the speed at which the kidneys deteriorate. If so, simple treatment may be available.
The need for a better prediction of their disease course is one of the reasons for this research. ”I can’t tell people whether they will have kidney failure at the age of forty or sixty. And knowing when to expect it makes a big difference,” says Salih, “then people can prepare. In a recent study among patients, they themselves indicated that they needed a better assessment of their disease progression.”
Salih conducts research with data from the DIPAK study, in which he has been involved for some time. DIPAK is a large consortium that runs in four centers where information has been collected from more than six hundred people. The people are followed for six to nine years. Salih will measure changes in various values in urine samples that indicate kidney failure, including crystals and inflammation values. He hopes to find a biomarker to better predict kidney failure in cystic kidneys. It could become a new indicator of how someone is doing, just as blood pressure and protein loss in the urine already are.
In addition, Salih hopes to find an easy treatment for this group of people. He is conducting a smaller study in which he adds potassium citrate, also known as citric acid, to the diet of patients with cystic kidneys. Either in the form of supplements or in the form of fruit and vegetables. It is known from animal experiments that citrate partially prevents the formation of crystals and his own research also shows that a low concentration of urine citrate can predict rapid deterioration of the kidneys. Salih therefore suspects that the benefits of a healthy lifestyle are even greater than known. And that more fruit and vegetables can actually influence the salts in the body and thus inhibit or even prevent kidney failure.
Salih adds that he cannot definitively find out with this small study. ”This is a creativity grant, so you have to approach the question ‘how can I make a big impact’ creatively. I hope that I get signals that citric acid may have a beneficial effect and that we can continue this into a larger study with more people to definitively demonstrate that it works.”
In addition to patients with cystic kidneys, this research may be of significance for another target group, namely their children. They have a fifty percent chance of contracting the disease. ”There is nothing for them yet. It is difficult because you deliberately do not diagnose children, because of insurance and because it can be stressful to know that you may become ill later. The diagnosis is not the primary goal in children. But if you know that your child has a chance of having cystic kidneys, you will of course give citric acid if that would help. It has few disadvantages. The sooner you start with easy interventions, the better. If you use it early, you can give people profits for years.”
Salih will receive a Creativity grant from the Kolff subsidy program to conduct this research.