16S Rdna Gene Sequencing Analysis in Functional Dyspepsia Treated with Fecal Microbiota Transplantation.

To the Editor: In recent years, fecal microbiota transplantation (FMT) has been developed into a therapeutic method for gastrointestinal diseases, including few adult functional gastrointestinal disorders (FGIDs) cases, which the immediate cure rate was 69.0% (1,2). Now we report the first pediatric FGIDs case who has 2-month symptom free after single FMT with remarkably changed 16s rDNA. A 5-year-old boy with 6-month recurrent abdominal distension after meals combined with nausea and vomiting was referred for further evaluation to our hospital. At initial encounter, he reported 1-month diarrhea, subsequently 2-month abdominal distention. His symptoms temporarily released after 2-week anti-Helicobacter Pylori therapy, l-glutamine and sodium gualenate granules, and Chinese traditional medicine. All symptoms, however, rebounded shortly. Abdominal enhanced CT revealed remarkable flatulence. He was diagnosed as functional dyspepsia. On his 6th month from disease initial, single FMT via nasal jejuna feeding tube was performed (3,4). The main symptoms disappeared immediately after the procedure, and consistently relieved up to 2 months. The patient reported normal appetite, bowel movement frequency, satisfactory weight, and back to school. 16s rDNA sequencing analysis reveals that the patient's fecal microbiota exhibits remarkably reduction of species richness and diversity compared with the healthy donor (Fig. 1), the FMT treatment significantly increased the species richness of the young patients (Fig. 2). It showed that the child's bacterial population after FMT was close to the donor (Fig. 3). Our results show FMT could be efficient treatment for pediatric FGIDs. This work is also limited by the number of case studies; therefore, more clinical cases and investigations are needed in the future.FIGURE 1: Alpha diversity of different feces samples. DNA extracted from feces collected from the healthy donor, and recipient pre-fecal microbiota transplantation (FMT) (−1), day 1 (+1), day 7 (+7), day 14 (+14) of after FMT was subjected to16S rDNA V6 libraries construction and sequencing. Alpha diversity measurement was performed to indicate variations in diversity (A, Simpson index) and species richness (B, Chao1 index) among these samples.FIGURE 2: The species composition of feces samples at phylum and family level. DNA extracted from feces collected from the healthy donor, and recipient pre-fecal microbiota transplantation (FMT) (−1), day 1 (+1), day 7 (+7), day 14 (+14) of after FMT was subjected to 16S rDNA V6 libraries construction and sequencing. A, The species composition at phylum. B, The species composition at family.FIGURE 3: The dynamic changes in microbiota population after fecal microbiota transplantation (FMT). DNA extracted from feces collected from the healthy donor, and recipient pre-FMT (−1), day 1 (+1), day 7 (+7), day 14 (+14) of after FMT was subjected to 16S rDNA V6 libraries construction and sequencing. Each cell is the sequencing tags proportion for each microorganism. The sequencing tags proportion data were scaled by row.