Urinary <i>D</i>-Lactate Excretion in Infants Receiving <i>Lactobacillus johnsonii</i> with Formula

Abstract

Background/Aims: Supplementation with certain probiotics can improve gut microbial flora and immune function but should not have adverse effects. This study aimed to assess the risk of D-lactate accumulation and subsequent metabolic acidosis in infants fed on formula containing Lactobacillus johnsonii (La1®). Methods: In the framework of a double-blind, randomized controlled trial enrolling 71 infants aged 4–5 months, morning urine samples were collected before and 4 weeks after being fed formulas with or without La1 (1 × 10⁸/g powder) or being breastfed. Urinary D- and L-lactate concentrations were assayed by enzymatic, fluorimetric methods and excretion was normalized per mol creatinine. Results: At baseline, no significant differences in urinary D-/L-lactate excretion among the formula-fed and breastfed groups were found. After 4 weeks, D-lactate excretion did not differ between the two formula groups, but was higher in both formula groups than in breastfed infants. In all infants receiving La1, urinary D-lactate concentrations remained within the concentration ranges of age-matched healthy infants which had been determined in an earlier study using the same analytical method. Urinary L-lactate also did not vary over time or among groups. Conclusions: Supplementation of La1 to formula did not affect urinary lactate excretion and there is no evidence of an increased risk of lactic acidosis.

Synbiotics, probiotics or prebiotics in infant formula for full term infants: a systematic review

“…Random sequence generation was done through computer randomization [21,37,38,43,44,50-52], random number tables [39,46] or block randomization [32,40,41]. The method used for random sequence generation was not clearly described in 10 studies [25,35,42,45,47,48,53-56]. …”

“…Allocation concealment was adequate due to central allocation using a computer [38], use of sealed envelopes [43,44,49], pre – coded or colour coded containers [32,50] and use of independent staff outside of study [46]. In the rest of the 18 studies, allocation concealment was not clearly demonstrated or described [21,24,25,35,37,39-42,45,47,48,51-56]. …”

A Randomized Double Blind Controlled Safety Trial Evaluating D-Lactic Acid Production in Healthy Infants Fed a Lactobacillus reuteri-containing Formula

“…The non-inferiority margin was set using the empirical assumption of a significant difference of a two-fold increase in urinary d -lactate concentration ie log(2) ≈0.7 mmol/mol creatinine. The mean and SD of the d -lactate concentrations in the study by Haschke-Becher et al were 2.25 mmol/mol creatinine and 1.46 mmol/mol creatinine, respectively 13. With a two-sided test at a 5% significance level and 80% power, 35 infants had to be included in each arm.…”

“…Sample size was calculated using data on urinary d -lactate concentrations in healthy infants reported by Haschke-Becher et al13 As data were skewed, they were log-transformed and the mean and standard deviation (SD) values estimated from the three groups in the study. The non-inferiority margin was set using the empirical assumption of a significant difference of a two-fold increase in urinary d -lactate concentration ie log(2) ≈0.7 mmol/mol creatinine.…”

Determining the safety of microbial cultures for consumption by humans and animals

“…In fact, it is the conclusion of scientific reviews that an underlying short bowel syndrome is a pre-requisite for the development of D(À)-lactic acidosis in humans (Hove, 1998;Uribarri et al, 1998). Although care should be taken when providing strains to the premature and neonate infant, several studies have addressed the D(À)-lactic acid levels in healthy infants, and concluded that when fed D(À)-lactic acid producing probiotics, there is no change in serum or urinary D(À)-lactic acid levels, and the probiotic feeding did not present an increased risk (Haschke-Becher et al, 2008;Connolly et al, 2005). As there are concerns for a special segment of potential consumers, i.e.…”