Changes in urinary citrate and lactate levels during the first months of life : The citrate/lactate ratio as a potential marker of mitochondrial function in renal tubular cells

Abstract

ABSTRACT: Background: Urinary citrate and lactate have been previously studied for a better understanding of renal tubule development. Never before had been related in a ratio. Methods: Urine samples from twenty five healthy infants were analyzed with GCMS, comparing lactate and citrate excretion depending on age and nutrition. Results: An increase in the citrate/lactate excretion ratio related to age was found. We also observed a marked influence according to the kind of feeding on this ratio, very influenced with creatinine levels. Breastfed infants showed a reduced pattern of excretion compared to the ones fed with formula, but when adjusted for creatinine this association appears to be inverted.