Probiotic Lactobacillus casei: Effective for Managing Childhood Diarrhea by Altering Gut Microbiota and Attenuating Fecal Inflammatory Markers

Abstract

Background: Acute diarrhea is a major cause of childhood morbidity and an economic burden for families. The aim of this study is to explore the effect of probiotics on clinical symptoms, intestinal microbiota, and inflammatory markers during childhood diarrhea.

Methods: Children (n = 81) aged six months to six years (mean age 2.31 years) hospitalized for acute diarrhea were randomized to receive probiotics (Lactobacillus casei variety rhamnosus; n = 42) or no probiotics (n = 39) orally twice daily for seven days. Feces samples were also collected to evaluate microbial content using a traditional agar plate and next-generation sequencing. Immunoglobulin A (IgA), lactoferrin, and calprotectin were determined by enzyme-linked immunosorbent assay (ELISA) and compared in different groups. Other clinical symptoms or signs, including fever, vomiting, diarrhea, abdominal pain, bloated abdomen, daily intake, appetite, and body weight were also assessed.

Results: Data were collected from 81 individuals across three different time points. Total fecal IgA levels in fecal extracts of the probiotics group were higher than those in the control group, reaching statistical significance (p < 0.05). Concentrations of fecal lactoferrin and calprotectin were significantly downregulated in patients with probiotic Lactobacillus casei variety rhamnosus (Lc) consumption compared to those of the control (p < 0.05). Probiotic Lc administration may be beneficial for gut-microbiota modulation, as shown by the data collected at one week after enrollment. Counts of Bifidobacteria and Lactobacillus species were elevated in stool culture of the probiotic group. Appetite and oral intake, body-weight gain, abdominal pain, bloating, as well as bowel habits (diarrhea) were much better in children receiving probiotics compared with those in the control group.

Conclusion: Fecal IgA increased during acute diarrhea under Lc treatment; in contrast, fecal lactoferrin and calprotectin were downregulated during acute diarrhea under Lc treatment. Probiotic Lc may be a useful supplement for application in children during acute diarrhea to reduce clinical severity and intestinal inflammatory reaction.

Keywords: Lactobacillus casei variety rhamnosus (Lc); calprotectin; immunoglobulin A (IgA); lactoferrin; microbiota; probiotics.

Figure 1

Differences in gut microbial composition between children with the probiotic Lactobacillus casei variety rhamnosus (Lc) supplement and the control group. Fecal samples of patients were collected at one week after enrollment in this study. Each color in this bar graph represents the corresponding taxon group at the phylum level in the legend.

Figure 2

Differences in gut microbial composition between children with the probiotic Lactobacillus casei variety rhamnosus (Lc) supplement and the control group. Fecal samples of patients were collected at one week after enrollment in this study. Each color in this bar graph represents the corresponding taxon group at the order level in the legend.

Figure 3

Differences in gut microbial composition between children with the probiotic Lactobacillus casei variety rhamnosus (Lc) supplement and the control group. Fecal samples of patients were collected at one week after enrollment in this study. Each color in this bar graph represents the corresponding taxon group at the family level in the legend.

Figure 4

Differences in gut microbial composition between children with the probiotic Lactobacillus casei variety rhamnosus (Lc) supplement and the control group. Fecal samples of patients were collected at one week after enrollment in this study. Each color in this bar graph represents the corresponding taxon group at the genus level in the legend.

Figure 5

IgA values (described as ng/g feces) from fecal samples of the probiotic group (gray bar), and the control group (white bar) collected on Days 0, 3, and 7 after therapy was initiated. Fecal samples of patients prescribed with probiotics (Lactobacillus casei variety rhamnosus) produced a significantly higher level of total IgA than those of the control (placebo). The data are represented as the mean ± SEM (n = 81), and statistically significant differences compared with the control group; * p < 0.05.

Figure 6

Grouped samples of fecal lactoferrin (μg/g feces) in children prescribed with probiotics (Lactobacillus casei variety rhamnosus) and the control (placebo). The figure shows the median, 10th, 25th, 75th, and 90th percentiles as vertical boxes with error bars. The remaining dots represent outliers less than the 10th or more than the 90th percentile. The fecal lactoferrin level was lower in patients with probiotic (Lactobacillus casei variety rhamnosus) consumption than those of the control (placebo) on Days 3 and 7 (horizontal line: Median; short dashed line: Mean; * p < 0.05).

Figure 7

Grouped samples of fecal calprotectin (μg/g feces) in children prescribed with probiotics (Lactobacillus casei variety rhamnosus) and the control. The figure shows the median, 10th, 25th, 75th, and 90th percentiles as vertical boxes with error bars. The remaining dots represent outliers less than the 10th or more than the 90th percentile. Fecal calprotectin levels were lower in patients with probiotic (Lactobacillus casei variety rhamnosus) consumption than those of the control on Days 3 and 7 (horizontal line: Median; short dash line: Mean; * p < 0.05).