The study is one of the first to directly link an absence of the organism, known as Oxalobacter formigenes, to the formation of the painful crystals. Previously, many researchers believed cystic fibrosis patients developed kidney stones in connection with intestinal malabsorption problems. Cystic fibrosis, one of the most common genetic diseases among Caucasians, afflicts approximately 1 in 3,200 people born each year in the United States. While kidney function is not greatly altered in these patients, kidney stones are an increasingly common complication as the life expectancy of these patients increases. In addition, nine out of 10 patients eventually are found to have a hardening of the kidneys from a build-up of calcium and oxalate.
Oxalate is a byproduct of digestion.
UF researchers collaborated with scientists from Alachua, Fla.-based Ixion Biotechnology Inc., Northwestern University, the University of Bonn and two German hospitals. The study participants, all residing in Germany and ranging in age from 3 to 39, had cystic fibrosis and showed no signs of an intestinal malabsorption problem. Their results were compared with findings from 21 healthy volunteers ages 4 to 44. O. formigenes appears to break down calcium oxalate before it can form crystals that evolve into kidney stones, he said. Oxalate is found in high concentrations in many foods, including asparagus, tea, broccoli, peanut butter, spinach and chocolate.