Alterations in Gut Microbiota After Antibacterial Treatment Due to Concomitant Disease Among Ambulatory Paediatric Patients

Abstract Antibacterial treatment is an important factor in shaping gut microbiota in children. The study aims to assess the effects of antibacterial therapy on microbiota composition. Parents of children with antibacterial treatment due to a concomitant disease submitted three children’s faecal samples (before the treatment, one week, one month after the treatment). Relative Abundance (RA) of bacterial taxa (16 rRNS) was compared between baseline and follow-up samples. Among 20 participants (median age 22 months) shifts within a month were noted for Bifidobacterium (46.80% vs 28.93% vs 41.50%; p = 0.087); Blautia (10.80% vs 8.94% vs 11.50%; p = 0.06), Anaerostipes (3.70% vs 0.32% vs 7.31%; p = 0.032), and Ruminococcaceae UCG-004 (p = 0.020) at baseline/one week/one month, respectively. Median RA of Eggerthellaceae decreased from 0.08% at baseline to 0.01% at one month (p = 0.040), while RA of Veillonellaceae increased from 0.01% at baseline to 0.04% at one month (p = 0.022). In conclusion, among the studied toddlers, antimicrobial treatment was associated with temporal alterations of gut microbiota, although a tendency towards the recovery of the pre-treatment microbial composition was noted. Persistent shifts of certain bacterial families could be minor markers for long-term changes in microbiota composition that should be analysed in dynamics.