Use of five classes of antibiotics is associated with increased risk for nephrolithiasis (kidney stone), suggests a case-control study in the Journal of the American Society of Nephrology.
Using UK healthcare databases, researchers matched 26,000 patients with nephrolithiasis to 260,000 control patients and compared their use of antibiotics in the 3 to 12 months before diagnosis.
After multivariable adjustment, use of sulfas, fluoroquinolones, cephalosporins, nitrofurantoin/methenamine, and broad-spectrum penicillins was associated with higher risk for nephrolithiasis, compared with nonuse. Children had the largest increase in risk. In an analysis of different time windows of antibiotic exposure, the risk remained elevated for 3 to 5 years after exposure for all but broad-spectrum penicillins.
The authors speculate that antibiotic-induced alteration of the gut microbiome could change macro-nutrient metabolism, thus leading to kidney stones. They note that they could not exclude direct antibiotic crystallization in the kidney.